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Vital tooth-whitening : An in-vitro study of three treatment modalities using argon laser, xenon pac-light and tungsten/halogen light systems
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Vital tooth-whitening : An in-vitro study of three treatment modalities using argon laser, xenon pac-light and tungsten/halogen light systems
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VITAL TOOTH-WHITENING: AN IN-VITRO STUDY OF THREE TREATMENT MODALITIES USING ARGON LASER, XENON PAC-LIGHT AND TUNGSTEN/HALOGEN LIGHT SYSTEMS by ROBERT SPENCE WRIGHT, B.D.S., M.S.Ed., M.S. A Thesis Presented to the FACULTY OF THE GRADUATE SCHOOL UNIVERSITY OF SOUTHERN CALIFORNIA In Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE CRANIOFACIAL BIOLOGY August 2000 Copyright 2000 Robert Spence Wright Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UNIVERSITY O P S O U TH ER N CALIFORNIA TMK 6MADUATS SCHOOL UNI VCRSITY PAMK LOS AMOCLSS. CALIFORNIA 10007 This thesis, written by Poke nr sPe/jce Cufi.i&trr under the direction of A ii— Thesis Committee, and approved by all its members, has been presented to and accepted by the Dean of The Graduate School, in partial fulfillment of the requirements for the degree of Master of Science 0M B August 8, 2000 THESIS COMMITTEE — t ________ CIsfrOM c Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This work is dedicated to Gordon for his support and encouragement, and to my parents for their sacrifices to provide me with a professional education * * * * * Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS Page ii DEDICATION Page iii TABLE OF CONTENTS Page iv LIST OF TABLES Page iv LIST OF FIGURES Page v ABSTRACT Page 1 CHAPTER 1 : Background and Significance Page 57 CHAPTER 2 : Research Methodology Page 65 CHAPTER 3 : Results Page 73 CHAPTER 4 : Discussion Page 82 CHAPTER 5 : Conclusion Page 84 BIBLIOGRAPHY APPENDICES Page 96 APPENDIX “A” : Lasers in Dentistry: Supplement Page 107 APPENDIX “B” : Experimental Data Page 126 APPENDIX “C” : Statistical Treatment of Data Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Page 12 Table 1: Defects in Enamel Formation Page 16 Table 2: Extrinsic Enamel Stain Page 17 Table 3: Age-related Discoloration Page 18 Table 4: Defects in Dentine Formation Page 66 Table 5: Individual Time-ordered Mean Measurements Page 67 Table 6: Individual Time-ordered Mean Differences Page 68 Table 7: Color Progression L* Page 69 Table 8: Color Progression a* Page 70 Table 9: Color Progression b* Page 71 Table 10: Color Progression E* Page 80 Table 11: Statistical Differences LIST OF FIGURES Page 4 Figure 1: Chemistry of Dental Bleaching Page 27 Figure 2: Internal Bleaching Page 28 Figure 3: “ Walking Bleach'’ Technique Page 46 Figure 4: Additive Color System Page 48 Figure 5: Spectral Curves and Metamerism Page 50 Figure 6: Munsell Color Wheel Page 51 Figure 7: Munsell Color Solid Cutaway Page 53 Figure 8: CEELAB System Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT This study examined, in vitro, the efficacy of three popular tooth-whitening modalities using a colorimeter [Minolta Chroma-Meter] to quantify the degree of color change. The instruments used to initiate and control to chemicals were the argon laser [Arago, Premier Laser]; xenon plasma arc light [Apollo Pac-Light, DMD Technologies] and a conventional tungsten/halogen curing light [3M], The distributors of the argon laser, and the xenon pac-light supplied the respective products [QasarBrite and Apollo Secret]. The manufacturer of the curing light did not make or recommend a specific product. In this case, a popular dual-curing, tooth-whitening agent, which has been on the market for many years [Hi-Lite, Fuji] was selected. Freshly extracted, virgin third molar teeth were collected from oral surgeons’ offices and were stored in plastic containers in 0.2% sodium azide solution until sterilized whereupon they were returned to isotonic saline. An attempt was made to replicate the conditions of the oral environment while adhering strictly to the manufacturers’ directions. The crowns of the teeth were sectioned 2-3 mm below the CEJ and then hemisected to provide two specimens. The specimens were then mounted on plastic containers and a jig and matrix was constructed to support the samples and colorimeter in a reproducible position for measurement. Great care was taken to ensure that the samples were kept hydrated during and between measurements. Colorimeter readings were taken before treatment, and at day 1, 14 & 28 following treatment. A series of t-tests were run to v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. test the null hypothesis. All systems resulted in tooth-whitening of the specimens. Neither system produced significantly greater tooth-whitening than the others. This result was premised on a measure of total tooth color change. An assessment of the individual components of light showed different results. The argon laser system had a more profound effect in reducing the “yellowness” of the tooth samples than did the tungsten/halogen system. The tungsten/halogen system had a more profound effect in brightening the tooth samples. There was no significant difference between the three systems in terms of their ability to modify the color of virgin teeth along the red-green axis, which remained constant. Specimens were also prepared to examine the effect of the respective treatments on the enamel topography using the scanning electron microscope. These samples were later treated to examine the effect of remineralizing agents on the enamel. SEM images will be recorded and analyzed in a subsequent pilot study to determine whether it is possible to successfully remineralize the chemically treated enamel surface. * Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. VITAL TOOTH-WHITENING : AN IN-VITRO STUDY OF THREE TREATMENT MODALITIES USING ARGON LASER, XENON PAC-LIGHT AND TUNGSTEN/HALOGEN LIGHT SYSTEMS Robert Spence Wright, B.D.S., M.S.Ed., M.S. CHAPTER I BACKGROUND AND SIGNIFICANCE Introduction Today, the general population relates modem dentistry, with its high technology, to improved facial esthetics, health and social success.7173 If the specialist of tomorrow is to build and maintain his or her referral base, a sensitivity to the patients’ esthetic desires, and a comprehensive understanding of the esthetic challenges which face the other team members is required. A lighter dentition is associated with health, youth and vigor. A recent survey of American women showed that 55% o f those aged between 34 and 55 would have their teeth whitened or straightened to create a more youthful appearance.36 Fashion magazines consistently rate tooth-whitening services high on their list of cosmetic enhancements. Is there any wonder that tooth-whitening is now the most commonly requested elective cosmetic service in the dental office?206 It has been 1 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. predicted that professionals with the highest skills and corresponding reputations w ill benefit from the billions of dollars being spent in health care over the next ten years.192 The first group of health care “specialists” , listed from patients seeking elective health care services, are “dentists providing cosmetic dentistry, including bleaching, bonding, veneers, invisible braces, etc.” Approximately 90% of all practicing dentists in the United States now administer tooth-whitening treatments. 30% of those perform in-office bleaching.26 This trend w ill continue with patients seeking an ever-increasing high level of esthetic restorative treatment.86-94 Along with this trend comes an increase in productivity and professional satisfaction for all members of the team.76 THE CHEMISTRY OF DENTAL BLEACHING Tooth-whitening continues to be an evolving science, as such, specialists, along with general dentists, have a professional obligation to remain current with developments in the field and the supporting literature. Nathoo has developed three classifications of extrinsic dental stain.146 Nl-TYPE Dental stain or direct dental stain: Colored material [chromogen] binds to the tooth surface to cause discoloration. The color of the chromogen is similar to that of dental stain. N2 TYPE Dental stain or direct dental stain: Colored material changes color after binding to the tooth. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. N3 TYPE Dental stain or indirect dental stain: Colorless material or a prechromogen binds to the tooth and undergoes a chemical reaction to cause a stain. The whitening mechanism o f bleaching is believed to be due to degradation of high molecular weight, complex, organic molecules that reflect a specific wavelength of light that is responsible for the color of the stain.38,64 66 The resulting degradation products are of lower molecular weights and less complex molecules that reflect less light and result in a reduction or elimination of discoloration [Fig. 1]. Darkly pigmented organic material responsible for enamel discoloration is composed of carbon ring structures with unsaturated, double, carbon bonds. With further oxidation these products are modified to hydrophilic, non-pigmented carbon structures with saturated carbon bonds [the saturation point]. Ideally, this is the point, at which, tooth-whitening should be terminated. If the degradation process continues, however, there is a further decomposition of organic matrix, which can lead to complete oxidation with generation of carbon dioxide and water, resulting in a total loss of enamel matrix protein.13,13,16,133,170,171 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 0 0 ° o 0 ° COa 0 ° ° ° o ° HjO. a a ^2°2 4 R—CH=CH—CH=CH—fl HjOj OH OH I I R -C H -C H -C H -C H -R I I OH OH 0 HO O n i n R-CH HjC—C 1 I OH OH OHI CH -R HjO CO] ” 2 ° COj COj COj HjO HaO Fig.1 Chemistry of Dental Bleaching Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bleaching to improve the appearance of teeth has been documented for over one hundred Years12,38,77 oxalic acid [Chappell, 1887]; hydrogen peroxide [Harlan, 1884]; chlorine [Taft & Atkinson, 1989]; heated hydrogen peroxide [Pearson, 1950]; “walking bleach technique” 35% hydrogen peroxide and sodium perborate [Nutting & Poe, 1976]; nightguard vital bleaching 10% carbamide peroxide [Haywood & Heymann, 1989]; the introduction of tooth-whitening and enzyme based dentrifices [Rembrandt, 1992]; ADA manufacturing standards established, 1994; light-activated bleaching agents, 1994; Argon, C02 laser, and plasma-arc activated chemicals [1994-97]; Diode laser as a vector in tooth-whitening [1999], From 1995 to 1998 there have been a variety of concentrations of bleaching gels containing re-mineralizing agents, fluorides and peroxide-free chemicals. In 1996, an international symposium concluded that there were no significant adverse effects of dentist-monitored "at-home” bleaching agents on the oral tissues/60 94 Peroxides and oxygen free radicals are reactive oxygen agents that are formed as natural products in all living systems that use oxygen. Reactive oxygen is usually only at very low concentrations because natural antioxidant protective systems prevent their accumulation.23,124 Reactive oxygen in the presence of free metal ions, such as Fe or Cu, combine to cause oxidative damage to the tissue.60 The safe use of peroxides in dentistry requires adherence to practices that minimize oxidative damage to oral cavity tissue.41,173 Hydrogen peroxide is more stable and thus has a longer shelf life in acidic solutions but it is more effective as a bleaching agent at 5 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. pH values closer to the dissociation constant.66 Furthermore, solubility factors suggest that alkaline solutions would be less likely to penetrate the pulp than acidic solutions. Alkaline solutions cause less demineralization o f tooth surfaces than acidic agents.64'66 The active ingredients in the bleaching agents must be quickly reactive with stains, non-reactive with dental or oral tissues, pleasant to use, and stable over long periods o f shelf storage. Hydrogen peroxide readily breaks down to oxygen and water, often accelerated by enzymes such as peroxidase. Carbamide peroxide and hydrogen peroxide are most common and have been used in dentistry for decades. Other names for carbamide peroxide are urea peroxide, carbamyl peroxide and perhydrol urea. Carbamide peroxide converts to carbamide and hydrogen peroxide.38 The carbamide portion is urea, a substance well tolerated by the human body.174 Sodium perborate comes in a variety of preparations being: monohydrate, trihydrate and tetrahydrate with varying content of oxygen. Sodium perborate solutions contain 95% perborate providing 10% of the available oxygen. It is liberated in the presence of acid, water or heat producing sodium metaborate, hydrogen peroxide and nascent oxygen. Sodium perborate solutions are alkaline. As they tend to be easier to control and safer to work with than Superoxyl, these products are more popular for intracoronal bleaching. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Historically, internal bleaching treatments of non-vital teeth using 30% hydrogen peroxide [Superoxyl] resulted in an incidence of cervical root resorption of 6-8%; combined with the application of heat the rate rose to 18-25% 62,63,176 The etiology of bleaching-related external root resorption is complex.79,85,114,115 For resorption to occur, there must be a combination o f deficiency in the cementum, exposing the dentine, or injury to the periodontal ligament, triggering an inflammatory response, I UA in? _ or an infection, sustaining the inflammation. ' The cementum deficiencies may be caused by a prior traumatic injury or by an incomplete CEJ.129,139 Such deficiencies expose permeable dentine that can allow toxic substances and bacteria from within the pulp chamber and root canal to emerge at the root surface, where they may cause an inflammatory process in the periodontal ligament.140 Hydrogen peroxide is capable of generating a hydroxyl radical, an oxygen-derived free radical, in the presence of ferrous salts. Hydroxyl radicals are extremely reactive and have been shown to degrade components of connective tissue, particularly collagen and hyaluronic acid. Dahlstrom et al. showed that there was a significant association between the production of hydroxyl radicals and the presence of tooth discoloration caused by blood components.32 Greatest yields of hydroxyl radicals occurred in teeth in which EDTA had been used to clean the pulp chamber prior to bleaching. It was concluded that hydroxyl radicals are generated during the thermo-catalytic bleaching o f root-filled teeth. 7 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Dahistrom postulated that the generation of these toxic, chemical by-products may be one of the mechanisms underlying periodontal tissue destruction and root resorption after intra-coronal bleaching.32 Internal bleaching may be accomplished using sodium perborate mixed with water.179 The esthetic outcome is still ceptable and the potential for resorption may be minimized.Carbamyl peroxide has a slower rate of reaction than hydrogen peroxide, especially at room and oral temperatures.94 Hydrogen peroxide releases oxygen within the first few seconds of contacting tooth surfaces while carbamyl peroxide remains active for 40 to 90 minutes after tissue contact.38 Oxygen combines with stain molecules in enamel to make stains more soluble. They are dissolved into the saliva or an oral rinse. The higher the concentration o f the active ingredient, the faster the decoloration. On the other hand, very high concentrations are more likely to irritate periodontal tissues.103 Scherer et al. found that nightguard bleaching actually had a therapeutic effect on inflamed gingival tissues. Leonard et al. found that the ratio of tooth sensitivity and gingival irritation is related to the frequency o f changing the solution. Improving the chemistry of the bleaching agent is one way to improve its effectiveness, another may be modifying it to be initiated and catalyzed by the use of high powered curing lights, ultra violet, plasma arc or laser light.56 66,214 It is always wise to question claims made by manufacturers’ in this regard, which have not been backed up by independent research. Both o f these chemical modifications must be tempered with the potential for an increased incidence of thermal trauma. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Recent research suggests that dental bleaching may not be as safe as previously believed. Nathanson [1997] reports “ sensitivity and discomfort may follow vital tooth bleaching ... care should be taken when patients have large restorations, cervical erosions or enamel cracks.” 144 Heling et al. [1995] found that teeth treated with either 30% hydrogen peroxide alone or in conjunction with sodium perborate were significantly more permeable to Streptococcus faecalis than those treated with sodium perborate mixed with water.101 Gurgan et al. [1997] found a statistically significant difference existed between the adherence of Streptococcus mutans to bleached and unbleached enamel specimens.82Zalkind [1996] reports that hydrogen peroxide, Dentlbrite, NuSmile and Opalescence were mainly associated with surface changes in the cementum, which exhibited more changes than other tissues.220 Koulaouzidou [1996] reports that the radicular penetration of hydrogen peroxide is related to the type of cemento-enamel junction.111 Bitter found that a 21-90 day exposure to SEM evaluation demonstrated alteration of the surface enamel, prismatic layer, frequently to the depth o f the enamel rods and possibly the dentin.13 Zhang et al. in a clinical trial involving 20 adult patients reported that HiLite 2gel [non-hydrogen peroxide] showed efficacy in whitening teeth with “ no apparent damage to the overall health of the hard and soft tissues.”221 On a more positive note, Attin et al. that remineralisation o f bleached enamel is improved by application of highly concentrated fluorides.8 More work should be encouraged in this area. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. High-powered curing lights have been used to accelerate the chemical reaction but have the disadvantage of producing significant amounts of heat potentially causing thermal trauma to the dental pulp.219 The halogen bulb powers the traditional curing light. The pac light [plasma-arc curing] uses a xenon bulb. When it creates light, instead of using a filament, it creates a plasma within the bulb. Irrespective of whether you use a halogen, pac or laser you must check their output periodically. ETIOLOGY OF TOOTH DISCOLORATION Tooth discoloration may be extrinsic, intrinsic, affecting dentine, enamel, pulp or any such combination. The etiology may be iatrogenic - a consequence of dentist or physician therapy, or, alternatively, dietary, environmental, patient-habit or agerelated. The condition may be either recent, temporary or permanent, and of local or systemic origin. The etiology of the condition impacts on the potential outcome of the bleaching treatment and its lasting prognosis.146 It is crucial, therefore, that a thorough patient history is taken prior to making a diagnosis and embarking on remedial treatment. Any concerns should be discussed with both the patient and the referring or restorative dentist. The clinical examination of the patient’s dentition should include an assessment o f plaque control, dental caries, surface texture, presence of external staining, type, quality and extent of existing restorations, dental sensitivity and pulpal status. Transillumination may reveal dental caries, and assist in determining the comparative levels of calcification. A complete series of periapical radiographs is essential for diagnosis and individual tooth assessment. 10 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Discoloration Associated with Pulpal Involvement Pulpal injury may be a consequence of bleaching, bacteria, physical, mechanical, thermal or chemical trauma, orthodontic tooth movement; erosion, abrasion, attrition, or destructive patient habits.148 Intra-Pulpal Hemorrhage Following acute trauma, intra-pulpal hemorrhage w ill give the tooth a reddish tinge. Occasionally, in the younger patient, the color may return to normal as the inflammation subsides. More often, the discoloration changes to gray-brown in a matter of days as the pulp becomes necrotic. In other cases, especially where the trauma was not as marked, the pulp may accelerate the process of secondary dentine formation and pulpal fibrosis resulting in reduction or obliteration of the pulp chamber.42 This process may span several years and result in a characteristic yellowing of the tooth. Occasionally, the pulp may respond initiating internal resorption [pink spot] with the eventual loss of the tooth. It is important that the endodontist determines early the prognosis for the pulp for possible need for intervention before the hemosiderin or necrotic pulpal toxins stain the dentine. Endodontic treatment and its sequelae must be balanced by the esthetic compromise posed by it and that of delayed calcification, together with the eventual difficulty of performing latent endodontics in a calcified canal. 11 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. DENTINE AND ENAMEL DISCOLORATION Developmental Table 1 Defects in Enamel Formation Amelogenesis Imperfecta_______ Endemic Fluorosis____________ Ricketts____________________ Chromosomal Anomalies_______ Inherited Diseases____________ Lead______________________ Thalidomide, Tetracyline_______ Childhood Illnesses___________ Malnutrition________________ Metabolic Disorders__________ Neurological Disorders________ Table 1. Defects in Enamel Formation Amelogenesis Imperfecta: Amelogenesis Imperfecta [Al] encompasses a complicated group of conditions that demonstrate developmental alterations in the structure of the enamel in the absence o f a systemic disorder. There are also numerous systemic diseases with associated enamel disorders, which are not considered isolated Amelogenesis Imperfecta. A vast number of rare disorders have been described in which dental anomalies have been observed. Some of these syndromes show enamel defects as the sole dental anomaly; others affect enamel as well as other dental tissues. Enamel agenesis demonstrates a total lack of enamel formation. At least 14 different hereditary subtypes of Amelogenesis imperfecta exist, with numerous patterns of inheritance and a wide variety of clinical manifestations. As proof of the complicated nature of the process, several 12 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. different classifications exist. The most likely accepted is that developed by Witkop. The formation o f enamel is a multistep process, and problems may arise in any one of the steps. In general, the development of enamel can be divided into three major stages: elaboration o f the organic matrix, mineralization o f the matrix, and maturation of the enamel. The hereditary defects of the formation of the enamel also are divided along these lines: hypoplastic, hypocalcified, hypomaturation. The estimated frequency of Amelogenesis imperfecta in the population varies between 1:700 and 1:14,000. As in any hereditary disorder, clustering in certain geographic areas may occur, resulting in a wide range of reported prevalence. In general, both deciduous and permanent dentitions are diffusely affected. Developmentally, Al in its various forms can be linked to these types of genes: autosomal dominant; autosomal recessive; x-linked dominant; x-linked recessive. For most situations, this classification is academic as bleaching of Al dentitions is merely an adjunct to comprehensive restorative treatment. Endemic fluorosis: The optimum concentration of fluoride in the drinking water for dental development is one part per million. When the level of fluoride intake approaches two parts per million noticeable white patches occur in the enamel. Such teeth are more resistant to dental caries but may be esthetically unappealing. When the levels exceed three parts per million, patchy brown discoloration o f the enamel occur. Higher concentrations than this in the drinking water can result in 13 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. pitting and anomalies in enamel formation. This condition was first reported in the literature, in 1916, by Black and McKay.12 An excessive amount of fluoride can be ingested by children or absorbed through the mucous membrane, resulting in mottling of the enamel. The type and extent of fluorosis is related to the age of the patient and the duration and quantum of the exposure. Genetic disposition may play a part, as well. The excess fluoride induces a metabolic change in the ameloblasts. The resultant enamel has a defective matrix and an irregular, poorly mineralized structure. Simple cases of white or brown spot fluorosis can be successfully bleached. In cases where the enamel is more opaque, bleaching may cause the white spots to become more pronounced. Preceding the bleaching with microabrasion can sometimes improve the esthetic outcome. Vitamin and mineral deficiencies: Ricketts, a vitamin D deficiency results in osteomalacia and developmental anomalies in the bones and as characteristic white patch hypoplasia in teeth. Scurvy, a vitamin C deficiency, together with deficiencies in vitamin A or phosphorous uptake during the formative period of the dentition may result in enamel hypoplasias. There are a variety of other chromosomal anomalies and inherited conditions which result in malformation of the enamel, too numerous to mention. In these cases, a clinical assessment of the condition o f the enamel is more important than determining the genetic etiology. 14 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Childhood illness: A common childhood illness or condition o f jaundice can result in blue-grey or yellow brown dentine discoloration from the circulating bilirubin and beliverdin. Congenital Eiythropoetic porphyria is an autosomal recessive disorder of porphyrin metabolism that results in the increased synthesis and excretion of porphyrins and their related precursors. These teeth demonstrate an unsightly deep purplish brown pigmentation of the dentine and fluoresce under LTV light. Erythroblastosis fetalis, an Rh factor incompatibility of the mother and infants blood, induces jaundice like conditions and associated dentine discoloration. Malnutrition: This has to be severe and prolonged before malformations in the dentition are evident. Metabolic disorders occurring shortly after birth or extended periods during the early years of life w ill be displayed chronologically on the developing teeth as linear areas o f hypoplasia. This may follow infection or kidney damage. Neurological disorders: This can result in developmental retardation and anomalies in dental development. Dental Caries Dental caries is the most common cause o f external and internal discoloration of enamel and dentine. The shade is related to the rate of the carious destruction with 15 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. the darkness being indirectly proportionate to the rate. KaVo have recently developed a diode laser for use in the detection o f dental caries. Table 2. Extrinsic Enamel Stain Table 2. Extrinsic Enamel Stain Dental Caries____________ Bacterial________________ Dietary_________________ Gingival Hemorrhage______ Chlorhexidene___________ Marijuana, Chewing Tobacco, Beetle Nut, etc.___________ Diet related: The consumption o f strong tea or coffee, especially when immediately preceded by orange or grapefruit juice, is a common dietary cause of external discoloration. Blackcurrant juice or cola drinks act by both etching and staining the tooth structure simultaneously. Bacterial stains: Chromophilic bacteria frequently seen in the deciduous or mixed dentition can cause a dotted or black-line stain. It has been documented that this type of bacteria is associated with lower than normal caries rates and that removal may result in recolonization o f the oral cavity by a more cariogenic flora. 16 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Gingival hemorrhage: Chronic gingivitis may induce staining from the breakdown of blood in the gingival sulcus. Chlorhexidene: Chlorhexidene acts in reducing plaque formation by altering the chemistry o f the primary pellicle by disturbing matrix formation. This altered pellicle does, however, attract more extrinsic stain not readily removed by tooth brushing. Marijuana/Tobacco: Smoking the recreational drug, marijuana, may produce characteristic linear green circumferential rings at the cervical margins. Smoking tobacco produces a yellow-brown discoloration especially on the lingual aspects of the teeth. Chewing tobacco causes a black-brown stain most noticeable on the buccal surfaces of the mandibular posterior teeth. This can be unilateral depending upon the habit, chewing tobacco, etc. Table 3. Age-related Discoloration Table 3 Age-related Discoloration Secondary Dentine Formation Thinning of Enamel________ Chipping and Micro fractures 17 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Age-related discoloration is a natural process resulting from secondary dentine formation and thinning of the enamel layer. Bleaching is particularly effective in older adults whose yellowed teeth have smaller pulps and greater dentine. These teeth generally tend to be less sensitive and can withstand higher bleaching temperatures. Table 4. Defects In Dentine Formation Table 4 Defects in Dentine Formation Dentinogenesis Imperfecta Erythropoetic Porphyria_____ Tetracycline/Minocycline I Genetic Anomalies_________ Hyperbilirubinemia________ Osteogenesis Imperfecta Dentinogenesis imperfecta: DI is a hereditary developmental disturbance of the dentine that may be seen alone or in conjunction with its related systemic hereditary disorder of bone, osteogenesis imperfecta. Most cases can be traced to Caucasians [English or French ancestry] from communities close to the English Channel. The disorder is autosomal dominant and occurs in about 1:8000 in the United States. There are three descriptive classifications of this disorder as outlined by Witkop: • Dentinogenesis imperfecta • Hereditary with opalescent dentine • Brandywine isolate. 18 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Both permanent and deciduous dentitions are affected. The teeth have a blue-brown discoloration, often with a distinctive translucence. The enamel frequently separates from the underlying dentine. Once exposed, the dentine often demonstrates significant accelerated attrition. Key radiographic features are bulbous crowns, cervical constriction, thin roots, and early obliteration of root canals and pulp chambers. Shell teeth have normal thickness enamel but extremely thin dentine with enlarged pulps. Other dentinal defects in dentine formation include: Erythropoetic porphyria; tetracycline and minocycline staining; Hyperbilirubinemia, and a variety of other genetic anomalies. Systemic Medications Tetracyline family: Tetracycline is a chelating agent for calcium forming tetracycline orthophosphate. Consequently, tetracycline, when consumed during the developmental period of the teeth, will result in a characteristic blue-grey or yellow-brown opalescent discoloration of the dentine. This is thought to be a photoinitiated reaction explaining why the incisors tend to be more affected than the molars. Jordan and Boksman proposed this classification: • Light yellow or gray stain • Yellow-brown or deeper gray stain • Brownish-yellow or blue-gray stain with distinctive banding The first two categories normally respond well to bleaching. The third category is less amenable to bleaching and the teeth usually have residual banding. These teeth w ill require veneers and in some cases full coverage crowns to achieve a 19 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. satisfactory esthetic improvement. Either treatment modality can induce lifechanging benefits for such patients. Tetracycline, a bacteriostatic antimicrobial, was commonly used for the treatment of chronic middle ear infections in children, and long-term therapy for acne vulgaris. Fortunately this drug is rarely prescribed now for pregnant women or young children. It is still used, however, in the treatment of cystic fibrosis and Rocky Mountain spotted fever. Minocycline is a semi-synthetic derivative of tetracycline. Unlike tetracycline, minocycline is poorly absorbed from the gastro-intestinal tract and does not combine readily with calcium but does so with iron forming a yellow-grey discoloration of varying severity. Success of bleaching is similar to that of tetracycline staining. Iatrogenic; A variety of restorative materials and procedures such as: dental caries, silver/mercury alloy stain, corroded steel pins, silver points, metal posts; degrading restorative materials and cements, endodontic obturation materials and sealers together with pulpal remnants can all lead to discoloration of the dentine. CONTRA-INDICATIONS TO BLEACHING Patient Selection Careful assessment of the patient may prevent subsequent difficulties.71 76-88 93 103 Those with emotional or psychological problems or those with unrealistic goals do not make good candidates for bleaching. 20 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Case Selection It should be determined at the consultation stage whether bleaching w ill improve the esthetic appearance o f the patients dentition, whether white spots may become more visible or where orthodontics, periodontics and/or restorative treatment is necessary to obtain the desired result.12,81,110,132 Both dentist and patient may be able to ‘test the waters” by using computer imaging. The general dentist or specialist should not hesitate in declining to treat a patient should his or her professional opinion dictate that bleaching is not in the patient’s best interest. Dentine Hypersensitivity These symptoms may be associated with severe cases o f attrition, abrasion, erosion or abfraction. Sometimes the most severe cases of hypersensitivity are associated with the early stages of the foregoing when there is recent exposure of the DEJ. This is hard to control when using home care bleaching trays.84 When the bleaching is conducted by the dentist, he or she can isolate the cervical areas with a rubber dam or protect the dentine with bonding agent. Suspected/confirmed Bulimia Application of bleaching agents with such patients may result in acute pulpitis. It is unwise for obvious professional reasons to embark on any irreversible dental procedure other than relief o f pain until such a time that the patient’s psychological 21 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. problems have been adequately addressed. Bulimic patients usually require a comprehensive course of restorative treatment involving veneers or crowns. Generalized Dental Caries And/Or Leaking Restorations Application of bleaching agents to patients who fall into this category may lead to severe generalized hypersensitivity. This is one reason against the sale of '‘do-ityourself, over-the-counter” home bleaching kits. All carious lesions and clinically unserviceable restorations should be taken care of before prescribing dental bleaching. Heavily Restored Teeth Teeth with visible tooth-colored restorations respond poorly to bleaching since the composite restorations do not lighten and hence become more evident after bleaching the tooth structure. The patient should be informed before treatment that a replacement of the pre-existing restorations may be required following the bleaching treatment, to idealize the esthetic result. Teeth With Opaque White Spots Application of bleaching agents to such teeth are likely to enhance the contrast between the good and hypocalcified enamel.9 Either microabrasion or selected amelopiasty and composite resin bonding may be required in conjunction to the 45,46,47, 195,1%, 197 bleaching treatments. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Teeth slated for bonded restorations or orthodontic bracketing The oxygen produced during bleaching remained in the enamel and dentine for up to two weeks. Oxygen interferes with the chemistry of bonding agents and will induce bonding failure.202-203 Such treatment should be delayed two to three weeks to allow complete dissipation of residual oxygen.l0-l9;) ALTERNATIVES TO BLEACHING Microabrasion Microabrasion is a technique for removing about 25 microns of the enamel surface.45 46 It is particularly useful for eliminating white or brown spots or surface roughness. The original protocol called for the use of 18% hydrochloric acid and pumice. Proprietary products such as Prema [Premier Dental Products] consist of a water-soluble gel containing a dilute concentration of hydrochloric acid and an abrasive compound. The gel is applied to the enamel surface with special rubber cups and mounts in contra-angle handpiece. The application time is short, about 10 seconds per tooth, and rinsed well with water. An assessment is made of color change and degree of wear and the process is repeated as required. When the desired result has been achieved the teeth are rinsed thoroughly with water then the residual solution neutralized with sodium bicarbonate. The teeth are rinsed again with water, dried and polished with a fine fluoride-containing prophy paste. 23 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The Mclnnes Microabrasion Technique A solution of 5 parts 30% hydrogen peroxide, 5 parts 36% hydrochloric acid, and 1 part diethyl ether is applied directly to the discolored areas for one to two minutes.134 Fine cuttle discs are then run over the enamel surface for 15 seconds to remove the softened enamel surface. INTERNAL BLEACHING OF PULPLESS TEETH Darkening and loss of translucency follows loss o f vitality, both prior to and subsequent to endodontic therapy. This can be related to internal hemorrhage into the dentine in the case of acute trauma, seepage of toxins from a necrotic pulp, staining from medicaments, cements or metal posts, or from the optical effects of dehydration/6 38 In the case of a single incisor tooth, one would be most reluctant to violate the tooth by preparing it for a full coverage restoration. Bleaching such unsightly, discolored teeth has been documented for over one hundred years. Superoxyl in concentrations of 30-35% have commonly been used. Superoxyl is a strong oxidizing agent and can readily bum soft tissue. The operator and assistant must take great care not to spill the solution causing needless injury to the patient or themselves. Heating Superoxyl solution, placed in the access cavity of the endodontically treated tooth initiates the release o f oxygen. The oxygen breaks down the darkly pigmented macromolecules into smaller lighter colored molecules. 24 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. An alternative treatment is to seal a pledget of cotton wool soaked in a mixture of Superoxyl and sodium perborate in the access cavity of the tooth for a period of 4-7 days. This has been termed the “walking bleach” technique.62’63174,173,176 Early internal bleaching of non-vital teeth using 30% hydrogen peroxide [Superoxyl] resulted in an incidence of cervical root resorption of 6-8%; when combined with the application of heat the rate rises to 18-25%. The etiology of bleaching-related external root resorption is complex as explained earlier in the chapter. Protocol For Internal Bleaching [Fig.2] • The first step is to examine the tooth clinically and radiographically, using all customary adjunctive diagnostic aids to determine whether the tooth requires re-treatment. • Take an intra-oral photograph of the tooth to be bleached with a corresponding tab from a ceramic shade guide placed next to it to record initial shade. • Perform prophylaxis of the objective and neighboring teeth. • Probe circumferentially to determine the outline of the CEJ • Place a well-fitting rubber dam exposing at least the adjacent teeth for shade comparison. • Tie off the treatment tooth at the gingival with dental floss. 25 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. • Prepare the access cavity in a conservative yet meticulous manner. Remove all endodontic obturation material, sealer, cement and necessary restorative material but no more dentine than is necessary. Ensure that all pulpal remnants and debris is eliminated from the pulp horns, which are often a common source for discoloration. • Remove 2-3mm of obturating material from the root canal. Irrigate the access cavity with copious amount of water. Dry well without desiccating. Introduce resin modified glass ionomer cement in Centrix syringe or with a lentulo spiral into the canal and access cavity. Contour the base so that it follows the outline of the CEJ and about 1mm incisal to it. The barrier material should be a minimum of 2mm in thickness. • Place a cotton pellet against the internal labial aspect of the tooth. Introduce Superoxol to the access cavity carefully from a syringe with a metal needle. • Heat the solution with a bleaching wand at low to medium setting or with a dry endosonic spreader. The temperature should be no higher than 15°F above body temperature. Repeat as required. • Rinse the tooth with copious amounts of water. Place a fresh dry cotton pellet in the access cavity and seal with Cavit. Photograph tooth with corresponding shade guide. Recall the patient in one week to assess the color after rehydration. Repeat procedure as necessary. If color change is satisfactory seal with glass ionomer cement. Recall patient in two weeks to place permanent bonded composite resin restoration in the access cavity. 26 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This w ill allow dissipation of residual oxygen, which would otherwise have interfered with the efficacy o f the bonding agent Fig.2 Internal Bleaching “Walking Bleach” Technique [Fig.3] The “walking bleach” technique is advocated where the results of chairside internal bleaching have been inadequate. • Dependent upon the severity of the residual discoloration and age of the patient you can use either sodium perborate and water or a mixture of sodium perborate and Superoxyl. The majority of cases external resorption appear in patients under the age of 25 years. It has been speculated that this is related to the more patent dentinal tubules. • Etching the dentine opens up the tubules permitting more of the bleaching agent to penetrate and therefore increase the risk of root resorption. Since 27 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. this does not appear to increase the effectiveness of the tooth-whitening, etching should not be performed. • Pack the paste into the access cavity and seal with a 2mm thick layer of Cavit to prevent intra-oral leakage. • Leave the mixture in place for up to a week with instructions that the patient returns to the dental office when the tooth appears lighter than the adjacent ones. This treatment may have to be repeated several times. • The shelf life of bleaching agents is short and there effectiveness is reduced by 50% after six months. • Similar directions apply for placement of final restoration. FigJ “Walking Bleach” Technique Note that increasing the amount of bleaching increases the risk of cervical resorption.51’63,79,85’115129 This should still be minimal provided that the barrier layer 28 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. is well placed. It has been documented that bleaching teeth may result in a reduction in fracture toughness.15’16'123'185,204'220 Recall Appointments Evidence of cervical root resorption does not usually manifest itself until six months post-operatively. Lesions detected two years later are usually too advanced to salvage the tooth. Early detection and repair enhances the prognosis. Repair of Cervical Resorptive Lesions Cases of initial resorptive lesions can sometimes be arrested using calcium hydroxide. In more severe cases, orthodontic extrusion or crown lengthening procedures may be necessary to access the lesion and avoid violating the biological width116'117 Where esthetics is not of primary importance, silver alloy is often the simplest and most predictable restorative material. Composite resin can provide an esthetic restoration but when dependent solely upon dentine bonding, the prognosis is limited. Dumfahrt & Moschen have described a technique for restoring cervical resorptive lesions with indirect porcelain inlays following clinical crownlengthening procedures.55 The shortfall in this technique would again be the dependence upon dentine bonding. 29 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. VITAL BLEACHING This can be categorized into over-the-counter tooth-whitening products, nightguard matrix bleaching and dentist/hygienist administered power-bleaching. Regardless of technique being used it is essential that a thorough clinical examination and prophylaxis be performed prior to applying tooth-whitening agents. Any soft-tissue problems, defective restorations and carious lesions should be corrected. It is good practice to record the shade of the patient’s teeth in a photograph with a tab from a shade guide. Patients with visible ceramic or composite restorations, should be informed that these will not be lightened by bleaching and may become more evident as a consequence. The patient should be advised that unless he plans to replace the existing restorations after bleaching, he should not proceed with this treatment. Patients who are planning to have veneers or all-ceramic restorations placed on their teeth but who had not contemplated vital bleaching should be advised that such treatment w ill reduce the amount of opacifier required to mask out the underlying tooth color.10 This will permit the ceramist to fabricate more translucent and vital looking restorations. Tooth preparation should be delayed for two to three weeks after bleaching to allow for rehydration and rebound, and to permit the dissipation of residual oxygen, which would interfere with the bonding agents. 30 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bleaching Agents Hydrogen peroxide, although served up in a variety of gels and pastes is still the most effective bleaching agent. It is available in concentrations from 30-50%. The gels used for nightguard bleaching are 5-22 % sodium perborate, which effectively produces the equivalent oxygen as 2-5% hydrogen peroxide but over a slower time period. It has been shown that the delivery o f hydrogen peroxide in an alkaline rather acid medium w ill significantly improve its oxidizing efficiency. Patient Preparation • The patient should be draped with a protective cape to prevent spillage o f the bleaching agent on his hands or skin. • The patient, operator and assistant should be supplied with protective eyewear. • No local anaesthesia should be administered which would otherwise inhibit the feedback about pain or discomfort from the patient. • Prior to application of the rubber dam, Oraseal - a light-cured resin, or Orabase paste can be applied liberally to protect the labial and lingual tissues. • Next place heavy rubber dam ligating the individual teeth with floss. Oraseal can also be applied to any amalgam restorations to reduce the build up o f heat from the light The holes should be smaller than normal, 31 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. rendering them further apart to ensure adequate coverage of the proximal gingivae. • Vaseline can now be applied to the patients’ lips before mounting the rubber dam frame. Wet gauze can also be placed over the patients’ lips to prevent thermal trauma from the heat lamp. It is important to keep rewetting the gauze during the procedure. Tooth Preparation Most authorities agree that there is little or no advantage in etching the enamel prior to bleaching and it results in a roughening and loss of surface enamel tissue [10 microns from the pumice and 20 microns from the etchant. This enamel must then be polished with diamond paste after bleaching to bring back the surface luster. This removes a further 20-30 microns of fluoride-rich enamel. There are situations where the enamel does not bleach in the absence of etching. Prior to applying the bleaching agent be sure to remove all excess Orabase, Vaseline or varnish. Pumice the teeth to be bleached and rinse thoroughly. Areas of cervical erosion, abffaction or attrition into dentine can be protected with bonding agent. In most situations follow the manufacturer’s directions and apply the gel or paste liberally 3-4mm thick. In cases o f hypoplasia or fluorosis where there could be spots or banding you should modify the application accordingly. Some teeth may be more discolored than others. As a rule, yellow-brown stains respond better than 32 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. blue-grey and the incisal half lightens easier than the cervical due to the varying degrees of thickness of the dentine. Traditional Vital Bleaching The traditional bleaching protocol called for the use of a special heat-producing lamp Upon application of the hydrogen peroxide solution to the teeth this lamp was placed about 12-14 inches from the patient’s face and left there for 20-30 minutes. This had the advantage of not requiring the dentist or assistant to move the light source from tooth to tooth. Although the heat source is set at a temperature not to cause thermal trauma to the pulp many patients complain that it gets uncomfortably hot on the skin of the face. After isolating the teeth with rubber dam a layer of single ply gauze is applied to the surface of the teeth. Since the Superoxyl solution is a liquid, the gauze acts as a wick and reservoir to retain the solution in close proximity to the teeth. Double thickness gauze is correspondingly applied over the rubber dam covering the lower lip to catch the drips and protect the mucosa. Other devices such as the rheostat-controlled, heating device have special metal tips of various shapes and sizes for getting into grooves and hollows. Intentional Endodontics and Intracoronal Bleaching Abou-Raas, in 1982, suggested performing intentional endodontics and intracoronal bleaching for patients with severe tetracycline staining.1 This protocol was proposed as being a “more conservative” treatment to full coverage crowns. 33 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. At that time, porcelain laminate veneers were in their infancy and tended to be rather opaque and monochromatic. Bonding agents did not have the predictability that they have at the present time. Today, tetracycline-stained cases w ill normally be treated by power bleaching and restored with veneers. In severe cases, however, a satisfactory esthetic result can only be achieved with full coverage crowns. AbouRaas published a follow-up report in 1998 claiming that excellent, permanent esthetic results were obtained with no side effects for some 112 teeth in twenty patients.2 CONTEMPORARY TOOTH-WHITENING MODALITIES Tungsten/Halogen Curing Lamp The new wave of vital bleaching in the 1980’s started with Fuji HiLite dual cure material [35% hydrogen peroxide]. The paste was mixed turning a green-blue color and activated with a standard composite curing light. As the chemical reaction progressed the paste changed to white, at which point no more oxygen was being produced. Nightguard Vital Bleaching This form of slow release custom matrix delivery is also known as the '"dentistprescribed, patient-administered” technique.86 An advantage of this technique is that it does not tie up the dental chair. The disadvantage is that it takes two to six weeks, some patients find this an inconvenience and there tends to be more 34 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. sensitivity. Originally, when these products came on the market, the patient had a choice of either sleeping with the bleach-filled trays during the night [4-6 weeks] or during the day [2-3 weeks]. Today, there are a variety of tooth-whitening gels on the market in a range of concentrations. Success of treatment is dependent upon the patient situation but is essentially dose and time related. As such, patientadministered bleaching is potentially open to abuse. The dentist should have the patient return to the practice once a week to monitor progress. Since the introduction of nightguard vital bleaching in the late 1980’s there have been a multitude of articles written on the subject, many by Haywood.86'" They conclude that dentist-supervised nightguard vital bleaching does not have any detrimental effect on the teeth or tissues. Common side effects such as blanching of the gingival papilla or crest and thermal sensitivity are transient. The color change will remain stable for 1-3 years." Fabrication of the Bleaching Trays Alginate impressions are taken o f the patients’ maxillary and mandibular arches. Care must be taken to avoid incorporating voids or drags in the impression. After disinfecting the impressions and thoroughly rinsing them, casts are poured in stone. The casts are then prepared for the vacuum-forming machine by cutting out the palate and vestibule. It is customary to treat one arch at a time allowing one to act as a control for the other. Reservoirs are placed on the labial surface of the teeth to be bleached just shy of the gingival margin. 35 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. A soft clear plastic sheet [0.020-0.035in] is placed in the vacuum-former, softened by heating then sucked down over the cast. Upon cooling the plastic matrix is trimmed with a scalpel approximately 3mm apically from the gingival margin facially and lingually in a scalloped manner. A rubber wheel in a micromotor can then be used to smooth up the rough edges. Delivery of the Bleaching Trays The matrix is tried in the patient’s mouth and relieved where there is tissue blanching or occlusal interference. The patient should be instructed to place a couple of drops of the gel into each tooth slot and then place the matrix gently over the teeth. If the nightguard is to be worn while sleeping only one application is required, and the gel concentration should not exceed 16%. For daytime uses the gel should be replaced every two hours. The patient should be cautioned about the antiseptic taste and the possibility of tissue irritation and thermal sensitivity. This should be transient. However, should the patient feel that this is excessive, he should discontinue use and return to the dentist for evaluation. The patient should be instructed to return once a week for three weeks for daytime wearers and once every two weeks for six weeks for nighttime wearers. Power Bleaching Power bleaching is the term given to accelerated, in-office, tooth-whitening procedures using either a xenon plasma arc curing light or a laser. The plasma arc 36 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. lamp was introduced in 1993. Shortly afterwards came the “ liquid rubber dam” . This is a light-cured resin gel, which can be painted on the gingivae and areas of the teeth, which you do not wish to bleach. The advantages are that it is much quicker to apply but does have a tendency to flow up onto the cervical area of the teeth under mouth temperature if you delay the curing. More care has to be exerted when applying the bleaching gel as, unlike the rubber dam, the lips and soft tissues are not protected. In most states the dental hygienist can use a plasma arc light but not an Argon laser. The recently introduced a low power diode laser curing light may be used by hygienists in some states. Advantages Of Power Bleaching Delegating the power bleaching to a dental auxiliary will generate more revenue for the practice, freeing up more time for the dentist to perform more skillful procedures. Most patients, given the choice, would rather have their teeth bleached in one visit rather than spend several weeks of tedious efforts with home-bleaching trays. The dentist has the ability to isolate areas such as abffactions or erosions with bonding agents to prevent sensitivity. Power Bleaching Protocol Operator, assistant and patient should wear protective yellow-lensed eyewear. The patient should be instructed to raise his hand should he feel a tingling sensation in his gums, lip or teeth if the temperature feels uncomfortably hot. A couple of 37 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Vitamin E capsules should be cut open and the oil expressed onto a glass slab. A number of cotton pellets should be placed in the oil and a pair o f cotton pliers should be at hand. Vitamin E is a powerful anti-oxidant. Hydrogen peroxide is a powerful oxidizing agent, which w ill readily bum soft tissue. If you notice blanching of the tissues quickly apply the vitamin E oil to the area. If you respond quickly, you can reverse the process before any damage occurs. The standard procedure is as follows: • Pumice the teeth • Isolate the teeth using bilateral cheek retractor and cotton rolls • Use a ligated rubber dam or apply light-cured resin dam extending from gingival crevice • If acid etching is necessary, apply 37% phosphoric acid gel for 15 seconds, rinse thoroughly and dry • Mix power bleach solution [QasarBrite, Apollo Secret etc.] following the manufacturer’s directions • Apply the gel 2-3mm thick over the labial surface of the teeth using a disposable brush • Expose one tooth at a time for 10 seconds. When the arch is complete repeat twice for a total exposure of 30 seconds per tooth. • Leave the gel on the teeth for an additional 5 minutes 38 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. • Remove gel with wet gauze then irrigate with copious amounts of water. Pumice teeth to remove residual exposed gel from enamel surface. Repeat process 2-4 times until desired result is achieved • Remove gel, irrigate thoroughly. Polish teeth with diamond paste and prophy with neutral sodium fluoride gel • Instruct the patient for the first two weeks to avoid coffee, tea, cola drinks which may stain the newly-bleached teeth. A REVIEW OF AVAILABLE LIGHT SOURCES Conventional Bleaching Light The conventional bleaching light supplied energy to enhance the bleaching action of hydrogen peroxide simply by adding heat. The heat caused a more vigorous release of oxygen and facilitated the dissolution o f the pigments. It is slow and ofren uncomfortable for the patient. Tungsten-Halogen Curing Light The standard curing light provides heat as well as stimulating the initiation of the chemical reaction by activating the light-sensitive chemicals in the bleaching agent. Slow at 40-60 seconds per application per tooth. 39 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Argon Laser True laser light is delivered to the chemical agent. Argon laser wavelengths are not attracted to water. The action is to stimulate the catalyst in the chemical. There is no thermal effect. As such there will be less dehydration of the enamel and subsequent rebound effect. It is quick at 10 seconds, per application, per tooth. Xenon Plasma-Arc Light This non-laser high intensity light produces a great deal of heat and therefore can only be applied for brief 3-second periods to the tooth. The action is twofold, thermal and stimulating the catalyst in the chemical. It is very fast hence there is a greater potential for thermal trauma. Diode Laser Light True laser light produced from a solid-state source. Ultra-fast, taking 3-5 seconds to activate the bleaching agent. This laser - [BlueLase, Premier Laser Systems] produces no heat. Laser bleaching Lasers are also used in the delivery of chairside bleaching agents. A detailed synopsis of the use of lasers in dentistry is provided in Appendix “A.” In a most basic sense, when laser energy is emitted and falls on a substrate, it may be transmitted, reflected or absorbed. It is most effective when it is absorbed. 40 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The C02 laser energy is rapidly absorbed by water, or by darkly pigmented watercontaining tissues. Argon laser energy is more effectively absorbed by darklypigmented tissues. Conceptually, the laser is thought to provide energy to the bleaching medium to undergo breakdown, providing the oxygen radicals for lightening or oxidizing the stained tooth. Some dentists use combined argon and C02 technique whilst others use argon alone.67 The argon group believe that the pigmented dark color of the tooth will actually absorb the energy (irom the argon laser, exciting the molecules and adding energy to potentiate the bleaching process. In addition, the laser is used to catalyze the oxidation reaction with the hydrogen peroxide. The free radicals of oxygen liberated in the process break apart the double valency bond into the simpler, less pigmented chain. Manufacturers of Argon lasers claim that there is no dehydration of the tooth with Argon wavelengths as they are not attracted to water and hence no rebound of color with rehydration of the tooth and also no sensitivity. Advocates of the combined laser system argue that when the tooth gel gets whiter, the pigmented tissues are no longer absorbing the energy from the argon laser so it becomes less effective. The C02 laser energy, which is absorbed within 0.1 mm of the water-containing substances, is then more effective. The rapid absorption of laser energy heats the solution more than an outside conventional heat source so the 41 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. pulp is purportedly not affected. A third group proposes the use of CO2 laser alone because the energy is so readily absorbed by the water-based bleaching agent that it is more effective than the argon laser for catalyzing the reaction. No wellcontrolled studies have been performed to show whether one modality is more efficacious than another. Rotstein et al. examined a variety of commercially available bleaching agents and found that different levels of phosphorous, sulphur and potassium were released from the enamel, dentine and cementum by these agents.172 Sulphur, a marker of proteoglycans, is present in the matrix of the hard tissues. Changes in the levels of this mineral may indicate damage to the organic component of the matrix. Little is known at present regarding the role of potassium, which is present intercellulariy and is therefore of interest. It is clear that cementum is more affected by changes in the sulphur levels following bleaching. This may be attributed to the higher concentration of organic components in this tissue. Changes in potassium levels occurred in all tissues, but decreases were more often found in dentine. The effect of bleaching on enamel, once thought to be of minimal consequence, has been recently challenged by several authorities. As previously mentioned, potentially the most significant change to bleached enamel is a reduction in fracture toughness. This may result from an altered organic matrix of the enamel. Further research is required in this field. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Research in Tooth-whitening Clinical studies o f patients comparing various, proprietary home-bleaching kits are potentially fraught with a plentitude of variables. Patient compliance, severity and nature of discoloration, pH and flow of saliva, existing restoration and dentine sensitivity are some. Suffice it to say that some types of staining and certain dentitions are more difficult to whiten than others. The patient situation appears to be more of a restricting factor than the product itself. Reports in the literature would support the claim that the majority of dentitions can be successfully lightened within a three-week period using carbamide peroxide in home-bleaching trays. The dentine sensitivity and the nuisance factor direct some patients to opt for in-office, tooth-whitening treatments or the so-called "power bleaching" methods. This research project compared the relative effectiveness o f argon laser, xenon paclight and tungsten/halogen curing light systems in an, in vitro, study using freshly extracted human teeth. In deference to the problem of the variables in quantum of discoloration, I opted to use virgin wisdom teeth as samples. These teeth had little or no extrinsic stain. Their color is natural and therefore serves as a better control. However, as the specimens are quite light to start with then the potential for shade-changes is limited. Color is a science unto itself. Much o f the original work done in this field in dentistry is credited to Bruce Clark who wrote a very informative series of articles in the Dental Digest in 193 l.29'3j Possibly the most renowned figure associated 43 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. with color in dentistry was USC’s Jack Preston who wrote and lectured extensively internationally on the subject in the seventies and eighties.161162163 Fundamentals of Color Science 162 Color is both objective and subjective. Light entering the eye falls on the retina stimulating the receptor cells [rods and cones]. The rods interpret the degree of dark or light on a grey scale whereas the cones [red, green and blue] are responsible for color sensation. The message is carried by the optic nerve, through the geniculate ganglion, to the optic center in the hindbrain where, the message is interpreted by the host. There are twenty rods for every cone therefore the eye is more sensitive to differences of value [lightness] than of hue [color]. There are three dimensions of color: Hue : the general range such as blue, green or red. The visible spectrum ranges from 380 - 760 nanometers. Violet blue, green, yellow, orange, red. Value: Brightness as measured on a grey scale with white the highest and black the lowest. Chroma: The relative saturation of a color with pink having less chroma than red. Ultra-violet light has wavelengths shorter than the visible spectrum. Teeth absorb ultra-violet light in the 350 - 360 range and reflect it in the 410 [blue] range imparting fluorescence to an object. Infra red [heat producing] wavelengths are longer than the visible spectrum and can only be seen using special optical devices. Primary colors [red, blue, green] are unique colors, which cannot be made by 44 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. combining other colors. Secondary colors are those formed by the mixing of two primary colors. The system o f combining colors of light [additive system] must not be confused with the mixing of pigments. White light is produced by combining red, blue and green light. Secondary colors are blue + red = magenta; blue + green = cyan; green + red = yellow. Secondary colors [light] are always brighter than their primaries as they contain more light. Subtractive color is the system of combining primary opaque pigment or filter colors. The subtractive primaries are cyan, magenta and yellow. Combination of these colors produces black [Fig.4], The secondary colors are cyan + magenta = blue, cyan + yellow = green, yellow + magenta = red. The secondary colors always have a lower value than the primaries because light is being removed. A primary hue and its opposing secondary hue are known as complementary colors. These are hues opposite one another on the color wheel. When true complementaries of the same saturation are mixed they will neutralize one another. In the additive color system they w ill produce white light, and in the subtractive system they will produce a black pigment. Although there are three primary hues of red, green and blue the eye sees four hues as being distinct. The psychological primary hues are red, green, blue and yellow. 45 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. c 0 1 0 3 ® 0 1 100 90 70 50 30 10 ^x>S^*-',J!r**,,S ii^ii! jf/ i f •- ■ ■> • •: .* '*. •ffSSt jzr+r zi 400 500 600 700 Wavelength (nm) 1S d s ? wg*f;.‘3 T*?C£"4SS 400 500 800 700 Wavelength (nm) • m • •• • • • . * •* £ ••••••;• 400 500 600 700 Wavelength (nm) 400 500 600 700 Wavelength (nm) Fig .4 Additive Color System A: Cyan plus magenta results in blue B: Cyan plus yellow results in green C: Magenta plus yellow results in red D: When all three curves are superimposed, almost no light passes, resulting in black. Light falling on a body may be absorbed, transmitted or reflected. Light absorbed is lost. Light reflected is the basis for “seeing color” . Light transmitted through translucent objects will be altered. If light is transmitted through a body and emerges unchanged, the body is transparent If some of the light is absorbed and some emerges, the body is translucent. 46 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. A red object only appears red because this wavelength is reflected. Other hues [wavelengths] have been absorbed. When light is reflected from an opaque body, the light may be characterized by a plot o f its spectral nature [spectral reflectance curve] using wavelength as the abscissa and the percentage of light as the ordinate. Similarly, a translucent body absorbs some wavelengths, and transmits the remainder. The spectral transmission curve is a plot of the spectral nature o f a transparent or translucent body with the wavelength as the abscissa and the percentage of light transmitted as the ordinate. Pairs of objects that appear to be the same color in a given light, but which have different spectral curves exhibit metamerism [Fig.5]. Observer metamerism occurs when people see the same colors differently as a result of physiologic variation. Matching colors of the same spectral composition are non-metameric. 47 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 400 500 000 Wavaiangth (nm) 700 Fig.5 Spectral Curves and Metamerism Metameric pair. The spectral curves of two fabrics that will match as the same shade of green if lighting conditions are proper. One fabric B: derives its color from the reflectance o f light in the green band. The other fabric A: reflects light in both the cyan and yellow bands, which results in the perception of green. If incident light is deficient in either the yellow or cyan components, green w ill not be seen and the fabrics will not match. Notice that the spectral curves of metameric pairs always intersect at least at these points. Approximately 0.001% o f the population, male and female, are monochromats having no color perception. Approximately 3% of males are dichromats and see only 2 of the 3 primary colors. Approximately 5% of the males are anomalous trichromats who see all three primary hues but make their match in an atypical manner. Numerous color tests may be used to discern the type and degree of anomalous color vision. 48 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The equation for color vision stimulus: Spectral Energy Distribution X Spectral Reflectance X Spectral Response = Stimulus for Color. Importance of a lighting environment Both the quantity and the quality must be defined. Adequate light is defined by, the task light and the ambient light. Ideally the task illumination to room illumination is 3:1. In a dental operatory 1 Oft.x 1 OftxSft high, approximately 12 x 4ft color corrected tubes are required to provide adequate ambient light.161 As a person ages the need for additional light to maintain the same viewing efficiency rises geometrically. Most fluorescent lamps have been rated for color correctness [comparison to standard daylight]. You can establish the quality of light by knowing the color temperature - 5500K is desirable. A Color Rendering Index of 90 or greater is needed for color matching. The spectral curve should approximate that of standard daylight i.e. near equal energy distribution throughout the visible spectrum. Munsell Notation Albert Munsell devised a system of color ordering [Fig.6]. This system divides the spectrum into ten basic hues [purple, purple-blue, blue, blue- green, green, yellowgreen, yellow, yellow-red, red, red-purple]. Each major division is further divided into ten major segments, each further defined to the second decimal, yielding 49 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 10,000 hues [Fig.7]. Value is divided into ten major increments, each further divided to the second decimal yielding 1,000 value increments. Chroma levels vary according to the ability of a hue to be saturated at a given value. The value of the Munsell color ordered system is that it is a psychologically-ordered system and lends itself to application to a variety of perceptual tasks such as shade comparisons in dentistry. SB 3/S II 5/S 3/S 'I S/S !' 5/10 380 3R Chroma so SOY Is V Biaek Fig.6 Munsell Color Wheel 50 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. w, Color Systems The Minolta CR-300 series Chroma Meters offer five different color systems for measuring absolute chromaticity [CIE Yxy (1931), L*a*b* (1976), L*C*H°, (1976), YZ (1931); Hunter Lab] and four systems for measuring color differences [A(Yxy), A(L*a*b*), A(L*C*H*), and Hunter Lab], Color as perceived has three dimensions: hue, chroma and value [lightness]. Chromacity includes hue and chroma [saturation], specified by two chromacity coordinates. Since these two coordinates cannot describe a color completely, a lightness factor must also be included to identify a specimen color precisely. For two colors to match, three quantities defining these colors must be identical. These three quantities are called tristimulus values X,Y, and Z is determined by the CIE [Commission Internationale de L’Eclairage] in 1931. CIE LAB System [Fig.8] The CIE (L*a*b*) 1976 color system more closely resembles human sensitivity to color. For this reason, it has been the standard used in dentistry for experiment and measurement in this field. The L* axis relates to the value [degree o f lightness on a grey scale]. High numbers are bright or white samples whereas low numbers represent dark or black objects. The a* axis measures the hue-chroma in the redgreen direction. Positive a* values are red; negative values are green. The b* axis represents the hue-chroma in the blue-yellow direction. Positive b* values are yellow; negative values are blue. 52 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. L*»*b* CotorOya lim Equal dtatonoaa in 9m OE 1931 a, y Chrornalc9y Digram do not lapmaant equal ddamncaa in color aa pereehadL The CC 1979 L’a f color ■>—m. however, more doaaly laptaaann human Mnatvity to color and Is Ohoam below. Equal dM vcaa in this syeWm approaimatoiy aqual parcelled color dWamnoaa.L’ ia 9m Ighamaa nartaMa, a* and b* ate the ilromafcay coonfcwMa. Thalr delning tqMtovwww tow n Mow. L- = 116( - i - ) « - l 9 a* = 5 0 0 K - J - ) " - ( - ^ - i * " ! b* = 2 0 0 R - J - ) * - ( - f - ) ,* J T* An In Tn £m where X, Y. Z: Me«urad triatimdua valuae d apactomn X». Yn. Zn: UManuluB mluaa of 9 » Rght aourea uaad (tfmwn batoar) “Light Source" indmi Xn Yn | Zn “C" 89.072 100.00 I 116225 “0m” 96.045 100.00 i 1091992 Tha above aquations apply only whan X/Xn, Y/Yn. and Z/Zn ara gmalar tmn 0.009988 When X/Xn. Y/Yn, and Z/Zn am laaa ta n 0.008966, tha aquations below ara used to mplace valuaa in the above aquations. ( )w is laplacad by 7787 ( Yn 119 Color dPterence valuas AL*. AS*, and Ab* are < A f-L '-L 'i Aar-9’ -d*. t m o n g o w onMng o n v w L*. r. or. Maaaued satoaa of specimen L \ 9 \ trc VMuaa of torgai color I t t odor dWamnce a£*w a atoo rwaaautad uatog 9m L W color oootfnatoe and ddbmd by 9m L W odor apace and odvdNmanoaAE** Ar«-v(AL*)»+(Aar)»+(Aijrp White A.-Wrgmedor 0. SWOnWiV GQBr A’: m>gai ootor m aw a m Idmwm Fig.8 CIELAB System 53 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The problem of matching shades of restorations to teeth has plagued the dental for a hundred years. Despite superlative composite resins and porcelains on the market today shade matching remains a daily challenge for the clinician. More so, today, given the increased expectations of the dental consumer. The advent of the toothwhitening phenomenon has added a further dimension to the range of difficulties. The dental industry has responded with a range o f super-light shades of composite resin, glass ionomer and porcelain to match bleached shades of teeth. This provides further evidence that the public is bleaching its teeth beyond what is natural. Communicating the desired shade and surface luster to the remote dental technician has always been a problem in prosthodontics. The most difficult challenge is the matching o f a single maxillary central incisor tooth. Highly glazed surfaces not only appear unnatural because of the glassy surface texture, but they reflect more light back to the observer, thereby causing a loss in the depth of chroma and general translucency. Conversely, crowns with a low surface luster allow more light to penetrate the surface and the reflection from pigmented layers cause an increase in chroma and general translucency. Since restorative materials and ceramics are generally unaffected by bleaching agents a new problem has entered the color matching equation. Patients now wish to bleach their teeth before and after restorative treatment. The need for patient education is paramount to the success of aesthetic restorative treatment. 54 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The gold standard in instrumentation is the Minolta Chroma-Meter colorimeter. The instrument is highly accurate but highly sensitive to distance, angulation and micro- movement. Attempts to utilize this instrument adapting it for intra-oral measurement have met with mixed success. A further complication with the Chroma Meter is that it cannot be sterilized. It is impossible to take two consecutive hand-held readings with any degree of accuracy. Most of the difficulty surrounds the construction of precision-fitting jigs to consistently position the lens and object in the same orientation for consecutive readings. In the materials and methods section my attempt to devise such a series of jigs w ill be described. A tooth will provide different colorimeter readings dependent on the degree of hydration of the tooth. A system has to be devised to prevent the samples from becoming dehydrated from the day of extraction to the day of final measurement. The teeth must be sterilized without damage and maintained during the study in an aseptic environment to prevent the surface colonization by stain producing microorganisms. Similar attention must be paid not to apply chemicals to the samples after treatment, which could also affect their color and brightness. A protocol was developed to address these concerns and eliminate the potential to incorporate more variables. 55 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The major component of this study was to compare the effectiveness of three dentist-applied tooth-whitening modalities. A second study is to investigate the effect of the respective systems on the tooth structure. The third part is to compare three methods of remineralization. The treatments were performed for parts two and three but the scanning electron microscope measurements will be performed after receipt o f funding. The null hypothesis Ho was proposed: There is no difference in the tooth-whitening effect of Argon laser, Xenon pac-light or Tungsten/Halogen curing light systems on virgin tooth samples. A statistical analysis was performed from the data generated to test the hypothesis. 56 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER II MATERIALS AND METHODS White chemical-resistant, polypropylene 250ml containers [Consolidated Plastics, Co. Inc., Twinsburg, OH] were delivered to 10 oral and maxillofacial surgeons offices in the greater Los Angeles area. The containers were marked: VIRGIN TEETH, POISON, 0.2% sodium azide [Polarchem Corp., Garden Grove, CA] in isotonic saline [FM Inc. Portland, OR], Material data and safety sheets MDSS were supplied. Affer approximately three weeks the containers were picked up. 142 teeth were collected [113 molars; 29 premolars]. Third molar teeth were selected for the experiment. An attempt was made to ensure that the teeth of the samples were approximately the same. As the majority of these teeth were virgin third molars they were relatively free from extrinsic stain and corresponded to A2-A3 or B2-B3 on the Vita shade guide. Three instruments were used to treat the specimens: Argon Laser [Arago, Premier Laser, Irvine, CA], Xenon Plasma Arc Light [Apollo Pac-light, DMD Technologies, Westlake Village, CA], Tungsten/Halogen Curing Light [XL 3000, 3M, St.Paul, MN] Premier Laser supplied QasarBrite [Interdent, Culver City, CA], and DMD supplied Apollo Secret, the respective tooth-whitening chemical kits. Shofu Dental Corp. [Menlo Park, CA] supplied Hi Lite, a dual activated toothwhitening k it. 57 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 80 plastic bur box containers [Brasseler, Savannah, GA] served as templates and trays for the samples. For descriptive purposes the components w ill be categorized as base and lid. A cardboard matrix was cut to fit the lid of the bur box and three 3mm holes were placed, equidistant along the center of the long axis o f the lid using a standard office hole-punch. The cardboard matrix was then placed on the lid o f 80 o f the boxes and the holes were marked using a permanent black marker. The black dots were then drilled out to leave a 0.1mm circle using a carbide acrylic trimming bur [Brasseler]. Only, the outside surface of the lids [40] were sprayed with matt black paint [Testors Corp. Rockford, II.]. The black paint was intended to obscure extraneous light from falling on the samples during the readings. The internal surfaces of corresponding container sections [40] were hand painted with matt black paint [Testors Corp. Rockford, II.]. This ensured that neither the tooth samples nor the holding fluids were in contact with the painted surfaces. The containers were then labeled numerically 1-10, according to treatment, on the left nearside of the lid [C(white)=Control; A(blue)=Argon; X(yellow)= Xenon; T/H(green)=Tungsten/Halogen]. The roots of the teeth were amputated from the crowns approximately 3mm from the C.E.J. using a diamond disc [ 946 806 104 365514 Brasseler] mounted on a laboratory micromotor [K10, KaVo America Corp. Lake Zurich, CL]. The crowns were then sectioned mesio-distally through the marginal ridges. 58 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The samples were then returned to the holding solution o f sodium azide before transferring to sterile isotonic saline then autoclaving at 118’C. for 25 minutes [Medical-Clave, Medic-Al, Conegliano, Italy]. After autoclaving and cooling to room temperature the samples were returned to fresh solution of isotonic saline. Using an aseptic technique the samples were randomly selected and mounted on the base of the containers, in groups of three, centered to correspond with the holes in the matching lids, using an insoluble silicone adhesive [Seal-All, Eclectic Products, Inc. Pineville, LA], As there is a facial-lingual variation in dimension of the samples there was often a teeter-totter effect when placing the viewing lid over the sample mount. If the distance between the object surface and the measuring device lens is not consistent, the recordings would be meaningless. To eliminate this potential error one end of the lid was held down so that the samples at the middle and that same end were in direct contact with the lid. The number to correspond with the base was then marked on the lid directly above. All samples were so identified. 40 other clear plastic lids were wiped clean with sodium azide solution then filled with sterile isotonic solution. The samples were inverted so that black lid supported the base with the samples facing downward in the saline. These sample mounts were kept submerged into the saline holding solutions between measurements to keep them hydrated. It is critically important not to allow the samples to dry out during or 59 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. between measurements as this would impact on the accuracy o f the reading. The holding solutions were changed daily to maintain sample contact and to prevent the development of a hypertonic saline solution through evaporation. Measurements were recorded on the C.I.E.LAB scale using a Minolta colorimeter, Chroma Meter CR-321 [Minolta Corp., Ramsey, NJ], This is a very sensitive instrument and variations in distance or angulation will result in error. The lid of the container is closed tightly down on the base coincident with the labeled markings. It is critically important that the 3mm porthole in the black lid is brought into close approximation, flush with the orifice of the colorimeter. A custom jig was built to ensure that the sample rack and colorimeter are accurately positioned for consecutive measurements. The Chroma Meter is quite heavy and can be laid on its side and remain stable. The measurements can be recorded remotely by pressing the display panel on the control box thereby eliminating the chance of moving the Chroma Meter during recordings. A jig was built by simply adding sheets of photocopy paper [approximately 4cm high] until a sample container placed on top would align perfectly so that the orifices on the lid corresponded with the aperture of the Chroma Meter. A grid pattern was then drawn in red ink to act as a matrix to ensure that the Chroma Meter and the sample boxes were position accurately. Once positioned the Chroma meter did not have to be moved. The room lighting therefore remained constant. Prior to the recordings, a 60 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. series of calibrations were performed on the Chroma Meter with the base plate provided. They were extremely accurate and consistent It was then determined not to recalibrate the instrument during the period of data collection thereby removing the variable o f inconsistency in repositioning the Chroma Meter on the custom jig. A series of five measurements were recorded on the 30 specimens in the control group. It was determined that the sample boxes could be removed and repositioned with a high degree of accuracy. Calibration. The Argon Laser, The Xenon Pac-light and the Tungsten/Halogen curing light, each had Built-in light meter which read the output. Prior to each series of tests, the light output for the respect instruments was tested. The colorimeter is first calibrated according to the manufacturer’s directions using the white standardization plate in the holder. The samples are then arranged in four columns of ten being: Control-C; Argon treatment-A; Xenon treatment-X; Tungsten/Halogen treatment-T/H. A series of baseline measurements were recorded for each o f the numbered groups. The samples were then returned to their holding solutions. 61 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Treatment of Specimens A series of baseline readings were first recorded for the three sample groups. The Argon laser, Xenon plasma arc light and Tungsten halogen curing lights were calibrated. To simulate the warm humid environment of the oral cavity it was determined to place the samples on a rack in a water bath [Hygrobath, Whipmix, Memphis, TN] that contained distilled water at 98’F. The first measurement is recorded from the sample adjacent to the labeled marker. The middle sample is read next followed by the sample at the opposite end from the marker. Argon Laser Group The QasarBrite gel was mixed according to the manufacturer’s directions and applied to the specimens 2-3 mm thick, three trays at a time [9 specimens] and placed on a rack in the water bath. Each specimen received a 10 second exposure [automatic timer] o f Argon laser radiation. The trays were then removed from the water bath and put to the side. The QasarBrite gel was applied to the samples on three more trays, which were placed on a rack in the water bath. The same treatment was administered. Those samples were replaced by the remaining four trays and the process repeated. The sample trays were randomized into three new groups of three, four and three. The gel was allowed to remain on the specimens for a total o f ten minutes. The specimens were then washed with copious amounts o f water to remove the gel and the excess water was removed with paper towel. The process was repeated for a second treatment Once the second treatment had been 62 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. administered the sample trays were once again removed and randomized. The process was repeated for a third time until each sample had received three treatments. The gel was again allowed to remain on the samples for ten minutes on the bench then rinsed o ff with water. The samples were now returned to their holding solutions. Xenon Plasma Arc Group The process was repeated for the Xenon group with the exception that the gel applied was Apollo [2-3mm in thickness]. The exposure time was 3 seconds [automatic timer] per specimen in sequence, repeated three times for a total of nine seconds per specimen. The treatment was repeated a second and third time. The gel was allowed to remain on the samples for ten minutes on the bench then rinsed off with water. The samples were now returned to their holding solutions. Tungsten Halogen Group The process was repeated for the Tungsten halogen group with the exception that the gel applied was Shofu HiLite [2-3mm in thickness]. The exposure time was 30 seconds per specimen. The treatment was repeated a second and third time. The gel was allowed to remain on the samples for ten minutes on the bench then rinsed off with water. The samples were now returned to their holding solutions. 63 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Control Group The control group treatment followed that of the Argon group except that the specimens were coated with isotonic saline. They received the same exposure of light as those receiving the Argon laser but without the QasarBrite tooth-whitening gel. Data Collection [Appendix B| Recordings were made of each sample group after 1,14 and 28 days. Individual readings were tabulated for L*, a* and b*. Color difference values [AE*ab] between baseline and subsequent measurements are expressed as a distance between two points in space and calculated according to the formula: AE*ab = [(AL*)2 + (Aa*)2 + (Ab*)2 ]m Statistical Analysis [Appendix C| A series of two-tailed t-tests at the 5% (.05) alpha level of significance were performed using Excel computer software [Microsoft, Redmond, WA] within and between the respective groups, the results were entered into tables and plotted on bar charts. 64 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER III RESULTS Data recorded by the Colorimeter before and after treatment are displayed in tables B1-12 in Appendix B. The means of measurements [L, a, b] for Saline, Argon, Xenon and Tungsten/Halogen as recorded on days [0, 1, 14 & 28] are displayed on Table 5 . Individual color differences: AL*, Aa*, Ab* and AE* for the respective treatment groups are displayed in Table 6. Color progression for L, a & b, from day 1 through 14 and 18 are shown graphically on column charts in Tables 7-10. 65 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. SALINE L a b DayO 33.07 -1.06 2.38 Day 1 32.87 -0.99 2.38 Day 14 32.33 -0.77 2.42 Day 28 33.36 -0.73 1.40 ARGON L a b DayO 34.16 -0.92 1.09 Day 1 38.48 -0.67 -3.19 Day 14 34.64 -0.90 -2.76 Day 28 34.00 -0.60 -2.94 XENON L a b DayO 38.51 -1.54 1.25 Day 1 41.80 -1.69 -2.31 Day 14 39.95 -1.16 -2.10 Day 28 40.40 -0.64 -2.17 T/HALOGEN L a b DayO 33.19 -0.93 1.56 Day 1 38.31 -1.26 -0.87 pay 14 37.19 -1.13 -1.24 pay 28 36.69I -1.00 -1.35 Table S. Individual Time-ordered Mean Measurements Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. DAYO-DAY 1 SALINE AL* -0.20 Aa* 0.07 Ab* 0.00 AE* 0.21 ARGON 4.32 0.25 -4.28 6.09 XENON 3.29 -0.15 -3.50 4.85 T/HALOGEN 5.12 •0.33 -2.43 5.68 DAY 0 - DAY 14 AL* Aa* Ab* AE* SALINE -0.74 0.29 0.04 0.80 ARGON 0.48 0.02 -3.85 3.88 XENON 1.44 0.38 -3.35 3.67 T/HALOGEN 4.00 -0.20 -2.80 4.89 DAY 0 - DAY 28 SALINE AL* 0.29 Aa* 0.33 Ab* -0.98 AE* 1.07 ARGON -0.16 0.32 -4.03 4.05 XENON 1.89 0.90 -3.42 4.01 T/HALOGEN 3.50 -0.07 -2.91 4.55 Table 6. Individual Time-ordered Mean Differences Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. OGL0URPR0GFE990N L* 600 600 400 aoo 200 1.00 QOO - 1.00 □ S d re ! -020 •074 029 □Aigcn 432 Q40 -016 □Xanon 329 1.44 1.8B □T/Hd 512 400 350 D*0>1 (fey 0-14 Table 7. Color Progression L* Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. COLOUR PROGRESaCN* 1 Q8 Q6 Q4 02 0 -02 -04 □Safine OAigon Q 07 029 Q25 002 Q33 032 □Xenon -Q 15 Q3S Q90 □T/Hai -033 -020 -007 0 *0 -1 4 0*028 Table 8. Color Progression a* 69 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. COLOUR FRDGRES90N If QSO QOO -QSO - 1.00 -1.50 •200 -2S0 -aoo -aso -400 □Seine QOO Q04 •QSB BArgon -42B -386 -403 □Xenon -3S5 -336 -342 □T/HbI -243 -280 -291 D q rO -1 0^ 0-14 t y O - 2B Table 9. Color Progression b* Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. COLOUR PROQRESaON E* 7 ---------------------------------------------------------------- OSaifw i O il 0.8 1.07 BArgon 6.09 3.88 4.05 □Xenon j 4.85 3.67 4.01 BT/Hai : 5.68 4.89 4.55 OayO-1 DayO-14 OayO-28 Table 10. Color Progression E* The data is calculated for a confidence level of 0.05 [two-tail]. The results indicate that treatment using Argon Xenon and Tungsten/Halogen systems all produced a significant color change [AE*] in the samples when compared to the control, which was treated using saline solution and Argon laser light. However, neither treatment system produced a significantly different total color change [AE*] firom the other. The initial total color change recorded after one day decreased noticeably after 14 days when stored in saline solution. 71 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Individual measurements of change in value, red-green axis shift and yellow-blue axis shift for the respective systems show that there was a significant increase in value [AL*] after treatment for Xenon, Argon and Tungsten/Halogen in ascending order. This change decreased to pre-treatment measurements for the Argon samples after 28 days, less for the Xenon samples and less still for the Tungsten/Halogen. Individual changes in the red-green axis were insignificant. Marked changes were recorded along b-axis with shifts away from yellow towards blue for all treatment groups. The changes remained fairly constant after 28 days. There was even a 1- unit change for the saline group after 28 days. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER IV DISCUSSION The CIE L*a*b* color order system is the accepted gold standard of the dental profession when calculating color change in teeth or restorative materials. It uses a mathematical system to describe the three dimensions of color within a color space of equally perceived gradations correlated with the human beings ability. 50% of the population can determine a color change greater than one unit. A positive number for AL* indicates an increase in value or brightness whereas a decrease is indicated by a negative number. A positive number for Aa* indicates a shift towards red on the red-green axis whereas a negative number indicates a shift towards green. A positive number for Ab* indicates a shift towards yellow on the yellow-blue axis whereas a negative number indicates a shift away from yellow towards blue. The Minolta Chroma Meter is a highly sensitive instrument. If the measurements are to be reliable, and the results of experimentation meaningful, then it is crucially important to control all variables, which could have a critical impact on the recording. These variables include consistency in: the distance and angulation of the lens of the colorimeter to the specimen; lack of movement of the colorimeter and the specimen; hydration level of the specimen, room lighting and adjacent wall and fixture colors. 73 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Hydration of the specimens during storage between recordings is also critically important. The design of this experiment adequately addressed all of these issues. Intra-oral recordings o f human teeth become ever more complicated as, in addition to problems with patient compliance, diet and oral hygiene, you have the variables of the reflected pink hue of the mucoperiosteum and soft tissue; pulpal vascularity; adjacent teeth and plaque or pellicle levels. There is also a greater range of color and surface texture of teeth, which have been erupted for a number of years. Most other similar in-vitro studies have attempted to collect sound, maxillary central incisors because of their flattish facial surface. These teeth would presumably be extracted for periodontal reasons. It is likely that such teeth would have been in the mouth for a number of years and had inadequate plaque control. When conducting experimentation of bleaching o f heavily stained teeth, one introduces another variable - that of the chemical and microbial makeup of the stain itself. Collecting sound maxillary central incisors in the USA is a challenge. Collecting such teeth of comparable levels and quality of discoloration is a further challenge. Collection of specimens in sufficient numbers to make a meaningful sample size w ill take an extended time. This now introduces another two variables. The amount of time the respected samples had been out of the patients’ mouths and the effect of the storage chemicals on them. 74 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Studies comparing the effectiveness of tooth-whitening systems often are addressing the ability o f a product to remove stain from teeth. This experiment wished to look at the tooth-whitening effect on the enamel and dentine of virgin or near virgin teeth. The reasoning behind this is that most patients presenting at the dental office requesting tooth-whitening services tend to be regular attendees who maintain a high level of oral hygiene. A more valid comparison of systems would then be their effect on the enamel and dentine of unstained teeth. The results show that there was a significant total color change for each of the three treatment groups when compared to that of the control approximately 4 units. The quantum of total color change between the respective groups was minimal. It should be noted that there was approximately one unit of change in the control group after 28 days. This would imply that the Argon laser light had no effect on the specimens. However, it would suggest that the saline storage solution itself had a minimal effect in lightening the tooth perhaps allowing some superficial staining, which otherwise would have been removed by the tooth-whitening agents, to go into solution. A closer look at Table 6 indicates that the total color change for the saline solution was largely the result of a shift in the b-axis from yellow to blue. The Argon system produced the greatest initial shift in the b-axis from yellow to blue followed by Xenon and then Tungsten/Halogen. This color shift remained virtually unchanged through 28 days at 3-4 units approximately 0.5 units apart. 75 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In the a-axis there was no significant shift except for the Xenon specimens, which moved almost I-unit in the red direction suggesting the removal of green pigment An interesting significant difference occurred between the specimens on the L-axis. The most profound increase in value occurred with Tungsten/Halogen system after initial treatment. T/Hal [5.12] was 1-unit greater than Argon [4.32] which, in turn, was 1-unit greater than Xenon [3.29], After 14 days, however, the Argon specimens returned dramatically by approximately 4-units to [0.48], After 28 days the change in L-axis stood at [0.29] for Saline; [-0.16] for Argon; [1.89] for Xenon and [3.50] for Tungsten/Halogen. More interesting though is how a Minolta colorimeter reading set at the CIE L*a*b* formula would record similar total color change measurements although made up from significantly different b-axis and Laxis components, and in the case of Xenon also the a-axis. Patients who request tooth-whitening services expect their teeth to appear less “yellow” after treatment. They do not think in terms of seeking brighter teeth. “ BriteSmile” is a proprietary system leased to dentists using their chemicals and a patented Xenon-Pac light delivery mechanism. It is therefore important to adequately differentiate between “whiteness” and “brightness” It is common practice for clinicians to photograph before and after views of patient’s teeth with a ceramic tooth from the original Vita shade guide beside them. A more accurate comparison may be to use the new Vitapan 3-D shade guide. 76 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The value of an object is determined by its relative position on a grey scale. The more a body reflects light the brighter it is perceived to be. Teeth are composed of various degrees of transparency, translucency and opacity. Light falling on a body may be absorbed, transmitted or reflected. Light absorbed is lost. Light reflected is the basis for “ seeing color” . Light transmitted through translucent objects will be altered. If light is transmitted through a body and emerges unchanged, the body is transparent. If some of the light is absorbed and some emerges, the body is translucent. A yellow object only appears yellow because this wavelength is reflected. Other hues [wavelengths] have been absorbed. When a tooth becomes dehydrated it loses some of its translucency. It becomes more opaque and therefore reflects more light appearing brighter. If an etching agent is applied before bleaching there is the potential to enhance the tooth-whitening effect. However, the etchant tends to reduce the natural glaze of the enamel imparting a “ frosted” look to it reducing its brightness. Teeth treated in such a manner may appear “whiter” after treatment but appear less “white” after subsequent polishing. It is the presence of water in the enamel and dentine, which affords a tooth its translucency while increasing the “ grayness” . A ll specimens in this study were kept hydrated by storing in isotonic saline solution between measurements. The solutions were replaced daily. The difference between treatment groups in the rebound effect of the value in the L-axis would suggest that there was a disparity between the groups in the extent or depth o f dehydration. It cannot be readily explained away as being proportional to a linear progression related to the duration 77 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. of the exposure to the curing “ light” . Xenon was the shortest at 9 [3x3] seconds, Argon at ten seconds and Tungsten/Halogen at 30 seconds. Similarly, it cannot be readily explained as related to heat produced. Xenon is the hottest followed by Tungsten/Halogen and Argon with virtually no heat. Unlike the CO? laser, the Argon laser is not attracted to water. As such, Argon laser wavelengths w ill not search out water. This may suggest that there is less dehydrating effect with the Argon system and help explain the profound rebound in the value. Perhaps, this reflects a similar profound rehydrating effect. If the Argon laser is removed from the equation it will be easier to explain the results in terms of intensity of heat and duration of application o f the heat/light source for the Xenon and Tungsten/Halogen systems. It has been shown that a reduction in fracture toughness follows a reduction in hydration level of a tooth. After 28 days the specimens the specimens treated with the Tungsten/Halogen system had only decreased by 30% in value. Should this be directly proportional to the hydration level this would suggest that the Tungsten/Halogen system could be potentially most structurally compromising to the tooth. This, in turn, would suggest that the Argon laser system caused the least, if any, harm to the tooth. This has yet to be experimentally determined. It would be interesting to design a study to look into the claims o f the laser system promoters that there is virtually no color rebound or post-operative sensitivity with laser tooth-whitening. 78 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In terms of actual reduction in the “yellowness” [chroma] of teeth, the Argon laser system has a significantly more profound effect than the Tungsten/Halogen laser. This is calculated statistically at a 0.05 confidence level and two-tailed analysis. For interest sake, if the data were calculated using a one-tailed analysis of a directional hypothesis then there would also be a significant difference between the Argon and the Xenon systems for AL* and Aa* [Table 11], 79 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. SIGNIFICANT DIFFERENCE: ONE TAIL VSL TWO TAIL DAY 0 - DAY 1 AL* Aa* Ab* AE* Argon - Saline 2t 2t 2t Argon - Xenon Argon - T/Hal 2t 2t Xenon - Saline 2t 2t 2t kenon - T/Hal 2t T/Hal - Saline 2t 2t 2t SIGNIFICANT DIFFERENCE: GINE TAIL VS. TWO TAIL DAY 0 - DAY 14 AL* Aa* Ab* AE* Argon - Saline 2t 2t Argon - Xenon Argon - T/Hal 2t 2t Xenon - Saline 2t 1t Xenon - T/Hal 1t 1t T/Hal - Saline 2t 2t 2t SIGNIFICANT DIFFERENCE: ONE TAB. VS. TWO TAIL DAY 0 - DAY 28 AL* Aa* Ab* AE* Argon - Saline 2t 2t Argon - Xenon 1t 1t Argon - T/Hal 2t 2t Xenon - Saline 2t 2t Xenon - T/Hal 2t T/Hal - Saline 2t 2t 2t Table 11. Statistical Differences Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In a subsequent study we hope to look at the effect of the respective systems on the structure of enamel and the respective benefits of various remineralizing solutions. It would be beneficial to the profession to design a study to compare fracture toughness of specimens treated with similar systems. Notwithstanding these findings, it is interesting to note that the specimens were shown to approximately 12 faculty members and residents at (JSC School of Dentistry. All of these parties came to similar conclusions that: in terms of apparent whiteness, from a clinical viewpoint, that the Argon laser system treated samples appeared “ whiter” than did the other specimens followed by Xenon, Tungsten/Halogen and the Saline controls. 81 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER V CONCLUSION Based on statistical calculations performed on data collected using the Minolta colorimeter [Chroma Meter CR-321] these were the findings: 1. There is no significant difference between the respective effectiveness of the Argon laser, the xenon plasma-arc light, and the Tungsten/Halogen light systems in tooth-whitening in virgin teeth, as measured by total color change AE*ab. 2. The Argon laser system had a more profound effect in reducing the chroma Ab* [“yellowness”] of virgin teeth than did the Tungsten/Halogen system. 3. The Tungsten/Halogen system had a more profound effect in increasing the value AL* [brightening] the virgin teeth than did the Argon system. 4. There is no significant difference between the three systems in terms of their ability to modify the color o f virgin teeth along the red-green axis Aa*. 82 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The results of this study would suggest that all three systems are capable of producing four units of total color change in virgin teeth upon one application. It would appear that relapse of total color change may be a function of rehydration of the specimens. The dependence upon total color change alone may not be a valid means of assessing the tooth-whitening effect of various systems. The human eye and the use of a comparative three-dimensional shade guide may offer a more clinically meaningful gauge o f tooth-whitening effectiveness, given that this remains the ultimate test in clinical practice. * * * * * 83 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. BIBLIOGRAPHY 1. Abou-Raas M. The elimination of tetracycline discoloration by intentional endodontics and internal bleaching. J Endod 1982; 8 : 101. 2. Abou-Raas M. Long-term prognosis of intentional endodontics and internal bleaching of tetracycline-stained teeth. Compendium 1998; 19(10): 1034-8, 1040-2, 1044 passim. 3. ADA Council on Dental Therapeutics. Guidelines for the acceptance of peroxide-containing oral hygiene products. 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Bleaching o f the discolored pulpless tooth. JADA 1958; 56. 64-68. 160.Ploeger BJ, Robinson RA, Christensen RP. Quantitative in vivo comparison of five carbamide peroxide bleach gels. J Dent Res 1991; 70(abstr. No. 889): 376. 161.Preston JD, Ward LC, Bobrick M. Light and lighting in the dental office. Dent Clin N America 1978; 22: 431 -451. 162.Preston JD, Bergen SF. Color Science and Dental Art. C.V. Mosby Co., St.Louis, 1980 Chapters 1,2&3. 163 . Preston JD. Current status o f shade selection and color matching. Quintessence Int 1985; 16:47-58. 164.Reinhardt JW, Eivins SE, Swift EJ jnr., Deheny GE. Quintessence Int 1993; 24: 379-384. 165.Robertson WD, Melfi RC. Pulpai response to vital bleaching procedures. J Endod 1980; 6 : 645-649. 166.RoIla G, Saxegaard E. Critical evaluation of the composition and use of topical fluorides, with emphasis on the role of calcium fluoride in caries inhibition. J Dent Res 1990; 69: 9 (Spec Iss.), 780-785. 167.Rosensteil SF, Gegauff A, Johnson W. Duration of tooth color after bleaching. J Am Dent Assoc 1991; 122: 54-59. 168.Rosensteil SF, Gegauff AG, McCafferty RJ, Johnston WM. In vitro color change with repeated bleaching. Quintessence Int 1991; 22: 7-12. 169.Rotstein I. Role of catalase in the elimination of residual hydrogen peroxide following tooth bleaching. J Endodon 1993; 19: 567-9. 170.Rotstein I, Danker E, Goldman A, Heling 1, Stabholz A, Zalkind M. Histochemical analysis o f hard tissues following bleaching. J Endod 1996; 22: 23-6. 171.Rotstein I, Friedman S, MorC, Katznelson J, Sommer M, Bab, I. Histological characterization of bleaching induced external root resorption in dogs. J Endod 1991; 17:436-41. 172.Rotstein I, Lehr T, Gedalia I. Effects o f bleaching agents on the inorganic components of human dentine and cementum. J Endod 1992; 18:290-3. 173.Rotstein I, Lewenstein I, Zuwabi O, Stabholz A, Friedman M. Effect of cervical coating of ethyl cellulose polymer and metacrylic acid copolymer on the radicular penetration of hydrogen peroxide during bleaching. Endod Dent Traumatol 1992; 8 : 202-5. 92 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 174.Rotstein I, Mor C, Friedman S. prognosis for intra-coronal bleaching with sodium perborate preparations in vitro: 1-vear study. J Endodon 1993; 19: 10- 12. 175.Rotstein I, Torek Y, Lewinstein I. Effect o f bleaching time and temperature on the radicular penetration of hydrogen peroxide. Endod Dent Traumatol 1988; 4: 32-6. 176.Rotstein I, Torek Y, Misgav R. Effect of cementum defects on radicular penetration of 30% hydrogen peroxide during intra-coronal bleaching. J Endodon 1991; 17: 230-3. 177.Rotstein I, Wesselink PR, Bab I. Catalase protection against hydrogen peroxide induced injury in rat oral mucosa. Oral Surg 1993; 75: 744-50. 178.Rotstein I, Zyskind D, Lewinstein I, Baumberger N. Effect o f different protective base materials on hydrogen peroxide leakage during intracoronal bleaching in vitro. J Endod 1992; 18: 114-117. 179.Rotstein I et al. In vitro efficacy of sodium perborate preparations used for intracoronal bleaching of discolored non-vital teeth. Endodont Dent Traumatol 1991; 7: 177. 180.Schroeder HE, Scherie WF. Cemento-enamel junction revisited. J Periodon Res 1988; 23: 53-9. 181.Schwabacher WB, Goddkind RJ, Lua MJ. Interdependence of hue, value, and chroma in the middle site of anterior human teeth. J Prothodont 1994; 3: 188- 192. 182.Seale NS, McIntosh JE, Taylor AN. Pulpal reaction to bleaching of teeth in dogs. J Dent Res 1981; 60: 948-953. 183 .Seghi RR, Denry I. Effects of external bleaching on indentation and abrasion characteristics o f human enamel in vitro. J Dent Res 1992; 71: 340-1344. 184. Shannon 1L, Edmonds EJ. Effect of fluoride concentration on re-hardening of enamel by saliva substitutes. Int Dent J. 1977; 28: 421-426. 185.Shannon H, Spencer P, Gross K, Tira D. Characterization of enamel exposed to 10% carbamide peroxide bleaching agents. Quintessence Int 1993; 24: 39-44. 186.Schulte JR, Morrissette DB, Gasior EJ, Czajewski MV. The effects of bleaching application time on the dental pulp. JADA 1994; 125: 1330-51. 187. Smith JJ, Cunningham CJ, Montgomery S. Cervical canal leakage after internal bleaching procedures. J Endod 1992; 18: 476-481. 188.Spasser HF. A simple bleaching technique using sodium perborate. NY State Dent J 1961; 27: 332-334. 189.Sproull RC. Color matching in dentistry. Part I. The three dimensional nature of color. J Prosthet Dent 1973; 29: 416-424. 190.Sproull RC. Color matching in dentistry. Part II. Practical applications of the organization o f color. J Prosthet Dent 1973; 29: 556-566. 191 .Sproull RC. Color matching in dentistry. Part III. Color control. J Prosthet Dent 1974; 31: 146-154. 93 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 192.Stanley TJ, Danko WD. The Millionaire Next Door. 1996, Longstreet Press, Marrietta, GA. 193 . Steiner DR, West JD. A method to determine the location and shape of an intracoronal bleach barrier. J Endod 1994; 20:304-306. 194.Sterrett J, Price RB, Bankey T. Effects of home bleaching on the tissues of the oral cavity. J Can Dent Assoc 1995; 61:412-20. 195.Swift EJ. Restorative considerations with vital tooth bleaching. JADA 1997; 128:60S-64S. 196.Swift EJ. A method for bleaching discolored teeth. Quintessence Int 1988; 19: 607-612. 197.Swift EJ jnr., Perdigai J. Effect of bleaching on teeth and restorations. Compendium 1998; 19(8): 815-820. 198.Tam L. Clinical trial of three, carbamide peroxide bleaching products. J Can Dent Assoc 1999; 65(4): 201-205. 199.Ten Cate JM, Arends J. Remineralization of artificial enamel lesions in vitro. Caries Res 1977; 11: 277-286. 200.Tipton DA, Braxton SD, Dabbous MK. Role of saliva and salivary components as modulators of bleaching agent toxicity to human gingival fibroblasts in vitro. J Periodontol, 1995; 66(9): 766-774. 201.Titley K. Scanning electron microscopic study observations on the penetration and structure o f resin tags in bleached and unbleached bovine enamel. J Endod 1991; 17:71. 202.Titley K, Tomeck CD, Ruse ND. The effect of carbarnide-peroxide gel on the shear bond strength of a micro til resin to bovine enamel. J Dent Res 1992; 71: 20. 203.Titley K, Tomeck CD, Ruse ND, Krmec D. Adhesion of resin composite to bleached and unbleached enamel. J Endod 1993; 19: 112. 204.Titley K, Tomeck CD, Smith DC. Effect of concentrated hydrogen solution on the surface morphology o f cut human dentine. Endod Dent Traumatol 1988; 4. 32-6. 205.Tong LS, Pang MK, Mok NY et al. The effects o f etching, micro-abrasion, and bleaching on surface enamel. J Dent Res 1993; 72: 67-71. 206.Trends in Dentistry. Longer, whiter, brighter: trends in tooth-whitening products and procedures. Dental Products Report 1996; July: 20-27. 207.Trope M. Cervical root resorption. JADA; 1997: 128: 56S-59S. 208. Wainwright WW et al. Rapid diffuse penetration on intact enamel and dentine by carbon 14 label urea. JADA 1950; 41: 135. 209. Walton RE, O’Dell NL et al. External bleaching of tetracycline bleached teeth in dog. J Endod 1982; 8 : 536-542. 210. Walton RE, Rotstein I. Bleaching discolored teeth: internal and external. Walton RE, Torabinejad M.(eds.) Principles and practice of endodontics. Philadelphia: Saunders, 1996; 385-400. 94 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 211. Wang JD, Hume WR. Diffusion of hydrogen ion and hydroxyl ion from various sources through dentine. Int Endod J. 1988; 21: 17-26. 212. Wasson W, Schuman N. Color vision and dentistry. Quintess Int 1992; 23: 349-353. 213. White DJ, Chen WC, Nancollas GF. Kinetics and physical aspects of enamel remineralization - a constant composition study. Caries Res 1988; 22: 11-19. 214. Whitening products and fluorides. The Dental Advisor 1996; 3: (4): 1-6. 215. Winter R. Visualizing the natural dentition. J Esthet Dent 1993; 5: 102-117. 216. Vogel Rl. Intrinsic and Extrinsic discoloration of the dentition (a literature review). J Oral Med 1975; 30(4): 99-104. 217. Yap AUJ, Bhole S, Tan KBC. Shade match of tooth-colored restorative materials on a commercial shade guide. Quintess Int, 1995; 26( 10): 697-702 218. Younger HB. Bleaching fluoride stain from mottled enamel. Texas Dent J 1939; 57: 380-382. 219.Zach L, Cohen G. Pulp response to externally applied heat. Oral Surg 1965; 19:515-530. 220.Zalkind M, Arwaz JR, Goldman A, Rotstein I. Surface morphology changes in enamel, dentine and cementum following bleaching: a scanning electron microscopic study. Endodont Dent Traumatol 1996; 12: 82. 221 Zhang W, Li Y, Yang J. Cytotoxicity and mutagenicity o f a non-peroxide based tooth-whitening gel. Loma Linda University, California. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX “A” LASERS IN DENTISTRY; SUPPLEMENT LIGHT AMPLIFICATION by STIMULATED EMISSION of RADIATION Albert Einstein came up with the quantum theory. Neils Bohr of Denmark theorized quantum mechanics as it applied to lasers. Theodore Maiman created the first laser, in I960, when he used a flash lamp to fire photons at a ruby crystal. Much of the early, in vitro, work with the pulsed ruby laser was done by Stem and Sognnaes at UCLA. Early work on medical lasers was performed in the I980’s by an ophthalmologist by the name of W.D.Myers. In 1990 his brother, T.D.Myers, introduced the first soft tissue laser for use in dentistry. Electromagnetic light is divided into ionizing and non-ionizing. The ionizing waves are tissue-damaging as they interfere with DNA replication and cause mutations and anomalies. These area at the left end of the spectrum, have short penetrating wavelengths and include x-rays, gamma rays and ultra-violet rays. The non-ionizing electromagnetic rays are sub-divide into visible and non-visible. The visible rays are in the color spectrum from violet to red. The non-visible, nonionizing rays are comprised of infra-red, radio/television waves and microwaves. 96 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. All lasers with the exception o f Xenon Chloride and Argon Fluoride, which are not, currently, used in dentistry are non-ionizing and fall within the infra-red zone. Categorization of Lasers Lasers are described by their active medium, modified by their delivery mechanism. The lasers currently used in dentistry are: • Neodymium:YAG • Argon • Erbium YAG • C02 • Holmium:YAG • Diode The four commonest types o f laser are characterized based on the physical state of the active medium: • solid state; usually a crystalline rod about the size of a cigarette • semiconductor diode • gas • liquid dye Solid state laser rods consist o f a host crystal into which a small amount of dopant atoms are uniformly distributed. The rod ends are polished flat and very smooth to enable laser light to pass through the rod without optical distortion as it bounces back and forth between the resonator mirrors. Rods are usually 3-6 mm in diameter and 50-100 mm in length. 97 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Components of laser units Lasers require: • active medium [solid, liquid or gas or combination thereof] • population inversion [pumping mechanism] • optical resonator [mirrors] • excitation source [strobe lamp] • controller [microprocessor] • cooling sub-system The simplest form of laser is a system where light from a strobe lamp is directed perpendicular to the active medium placed in a rectangular chamber with a pair of mirrors facing each other at either end one of which partially permeable to laser light. The laser phenomenon When photons strike a normal electron the stimulated electron becomes excited and, in its attempt to return to its unexcited state, emits a photon. This photon strikes another excited electron and that electron releases two photons which strike other electrons and so on. This energy builds up inside the chamber. A small portion of this energy is transformed into laser light with the majority being converted into heat. The laser light is released through the partially permeable mirror in a collimated beam of monochromatic light. One exception is the Argon laser which is dichromatic with two specific colors of laser light. The remainder of the energy is converted into heat which must be dissipated from the laser unit. 98 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Laser energy and biomedical work Joule: 2500 joules of work are required to heat and convert I cc of water at body temperature 98.6°F. into steam[vapor]. This is particularly relevant to laser surgical applications where often the objective is to remove biological tissue, which is mostly water, by converting it into steam [vaporization] where it is removed through the high volume suction tubes. Laser energy is usually expressed in millijoules. Watt: Power is the rate of doing work usually expressed in watts. A watt is one joule per second. Laser delivery systems • Articulated arm [mirrors] • Hollow waveguide [CO? internally mirror-coated tube] • Optic fiber • Lens The fiber optic tube is made of glass or quartz. It is covered with a cladding and a plastic or rubber sheathing. Wavelength mechanics The laser wave is described in terms of its: • wavelength [nanometers] • amplitude [nanometers] • frequency [hertz] 99 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The delivery mechanism is described as being either continuous wave or pulsed [gated] In a continuous wave the peak and average power are the same. In a pulsed or gated mode, the laser may only be released for 1 microsecond per millisecond of time. In the case of the Nd: YAG laser the peak power is 1,000 -3,000 watts but only for one microsecond therefore the average unit of power is only 1 - 3 watts. Laser - Tissue Interaction • Reflection • Transmission • Scattering • Absorption In its surgical application we wish to have maximum absorption. Lasers behave in different ways dependent upon their respective active medium, delivery mode and target substance. CO? is highly absorbent in water. Argon is highly absorbent in hemoglobin. Argon is highly scattered in composite resin and enamel. Neodymium is mostly transmitted. Biological effect The biological effect is a combination o f the specific wavelength and the tissue characteristics. 100 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Power density The power density is the product of the exposure time multiplied by the spot size. With a larger spot size more energy is required to achieve the same effect. A smaller spot w ill concentrate the energy. Tissue response When the laser light exits the fiber optic rod the rays diverge with the area of the spot being equal to the square of the distance from the rod. A laser may cut on contact with the tissue but coagulate if there is a 1mm space between the rod tip and the tissue. Tissue Temperature °C. Tissue Effect 37 - 50 Hyperthermia 50 - 60 Coagulation 70 - 80 Welding/tissue fusion 90 - 100 Vaporization 100-150 Carbonization >175 Rapid cutting The zone of tissue impact forms a "‘bull’s eye’’ around the point of contact. The inner zone cuts, the middle zone coagulates and the outer zone suffers edema. Continuous wave Vs. Gated wave laser The CO2 laser is most efficient in the continuous mode with a 150 pm cut causing 100 pm of edema. Argon w ill cause a 50 pm cut and 300 pm o f coagulation. 101 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Nd:YAG will cause a 1.5 pm cut resulting in 4 -7 mm of coagulation. This factor is very important in dentistry, given that the biological width of the periodontium is only 3 mm. By converting a Nd:YAG laser from continuous mode to gated mode 50 pm cut will produce only 300 pm of coagulation. With the CO: laser however in the gated mode 1 0 0 pm cut w ill produce 100 pm of edema. Beam quality This relates to the smallest laser spot diameter than can be produced on the tissue, the roundness of the laser spot and how rapidly the laser spot diameter increases as the distance between the end o f the delivery accessory and the tissue is increased [i.e. how rapidly the beam diverges from the end of the delivery accessory]. Articulated arm delivery systems employ a distal lens to focus laser energy onto the tissue. Beam spots as small as 150 microns can be produced when used with CO: lasers. Such beams are generally very round and have a low divergence. As such laser spot size remains relatively constant with regard to tip to tissue distance. This is a particularly important feature when cutting contoured surfaces with “ hills and valleys” . 102 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Beam divergence Laser light travels in a collimated beam. In the case of the hollow waveguide and the optic fiber the beams are reflected continuously as they travel along the flexible curved delivery mechanism. For this reason unfocused beams diverge upon exiting the orifice. The degree o f effectiveness of the laser therefore is inversely proportional to the distance from the laser light aperture. Contact vs. non-contact use Contact use of a laser delivery accessory usually minimizes the size of the laser treatment spot on the tissue, and provides some amount of tactile feedback for the surgeon. Non-contact use facilitates adjustment of beam spot size on the tissue. Large beam spot size of several millimeters can be produced in the non-contact mode, permitting rapid treatment of larger areas o f tissue [assuming enough laser power is available]. Contact mode provides the surgeon with tactile sensation. Different modes are used to achieve different therapeutic effects. The specificity of certain laser wavelengths for specific colors enables ophthalmologists to direct a laser beam through the eye to effect tissue on the retina without damaging the lens or vitreous humor. Likewise they can direct a beam to the surface of the eye without harming the retina. 103 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Infection control In the operating theatre the entire operating accessory may be discarded after a single use. Such an expense of $100 is not practical in the dental office and now disposable distal end tip costing around $5 are being produced. A plume of vaporized tissue is produced during the lasing procedure. Eyes, skin and the nose should be protected. This is particularly important when lasing herpes lesions. There have been reports o f dentists developing herpetic lesions around the opening of the nose. Protective lenses, masks or face shields should be worn. A high-volume suction should be kept close to the surgical site. Laser operating range for soft tissue safety Ideally you should operate in the 2-4 watt range and maybe the 2-6 watt range at about 20 Hz. As you increase the frequency you correspondingly increase the power and risk of tissue injury if you keep the laser spot in one place. Operator, assistant and patient should have their eyes protected with special lenses with side shields at all times. Nd:YAG laser specifically w ill damage the retina and lens. Laser tip design This is an evolving area. Laser tips come in a variety of designs and shapes • disposable fiber tips • metal hot tips Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. • sapphire probes and scalpels • sculpted quartz fibers • dual effect fibers • temperature controlled quartz fibers • quartz cool tips Laser designs for hard and soft tissue surgery By now it should be obvious that it critically important to "match” the selected laser wavelength to the tissue being treated in order to obtain the desired level of absorption, optical penetration and surgical precision. Cost is the major obstacle separating the dentist from the laser unit. Prices range from below $20,000 to over $100,000. Lasers used to be categorized into either hard tissue or soft tissue. Some laser systems can do both. Generally however the soft tissue lasers cannot cut hard tissue whereas the hard tissue lasers often can. Hard tissue lasers are more expensive. The following lasers can be used for gingival displacement/curettage: • pulsed Nd:YAG • Argon • CO: • Diode • Holmium • Erbium:YAG 105 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Factors influencing laser effectiveness: • power level • wavelength • frequency • mode [gated/continuous] • temperature • contact/non-contact • distance • diameter of fiber or tip • environment of site [dry, wet, saliva, water, blood] Conclusion Lasers are in a second wave of evolution partially inspired by the computer electronic industry. Some fine tuning of the various systems has to be done and the price must come down for their use to be commonplace in general dental practice. * * * 106 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX "B NO)'»S(JDNOOS(00)g[NOm'TN<flO)U)IO(D( 3 0 lOP)r-S0 5 N5Q ( q ^ N U ) o n ? ^ r - s o ) T - N o s n N n » - t - n ® S ’rK « -r-iS o )n ^ o g i r i d d c ^ r r i r i i r i N d s d f O ^ ^ r i d ' t ' - i n d ’- t d ^ ' t C j i r j d d i-®S'r0)»00)(3S(D«)0)N(Mn^U)bNT-SfflNn(pl0'r5O2 n p 5 s n ^ o n n s ( N T - t M n O ' - ’- o > i f i s N ( 0 ( ,) n « - o c ' ( i o n r - ( o 7 d V ^ ? 9 9 ^ 7 9 d 9 d d Vd v O v 9 T T V 9 ^ 9 9 T T S N O O S r r r f f l p Q T - r - S f f l ' f » - b ^ 8 0 I O j " N r f f l ( O N I D ( M K .« o K O io tN rtn 5 » -® in n N (o in ® 0 )n a )s < jiS (o n N rs csicD^^QqpcNiT-T^oocriCTjobob^irir^t^^QtNCsitD onMnortcopuMtMCMnwtMOWwncoriPxon ao O cm n SO) o n o CM CO M- CO O t - CM CO CO C7> T— T— T— o «- CM CM a n v in CM CM CM 8 S CO O) ^ CM CM CM M in (D SOO O) CM CO M m ID ~ - <Dq>g>(pa)a)tt)<pa>(P(p<pg)(p(p(P(P(pa)(pa)<pip<ptt>(})<DiP(P aaaaaaaaaaaaaaaaaaaaaaaaaaagoj EEEEEEEEEEEEEEEEEEEEEEEEEEEE C Q C O C D C O C D C Q I S C O C Q C O C D C Q C D C D C D a i C Q Q C D C Q C D C D C Q C Q C Q C i J C Q C Q c n t o t n m i n w t n M w t n t n w t n O T W w c n O T W t n cocoot co co co co co co s CM$9 co si o S OOONNJintQiniDNffi N<-3Nind6o)(oniniB(OT- (M»-'r: r - M r - ' d ( O T - M : d < N ’- 9 CO © co CO O) Co C p ^ n T - CM S OON CM CO O s CO S ^ CO CD O CM CO O O N- Cn o d 8 CM 0Di-®oiniDOsinnso)»-cD(O rtUJOTCMCOinoiCOCMCM^COCMCMOO ( D N N I O O ) in n in cm CD 9 ° v 9 9 9 9 9 9 9 t 9 t 9 9 v 9 9 9 v n o i n i n M M D i - K s i - i n c o c M O s ,» t V ° 9 9 9 o> CO CO CM CM 5 co ? in cm n CO CM CO M - CO M " o Ul - j m< O ■»- CM CO » " C M C O M , i n ( O N - I D O ) T - i - > - » - r - r - O Q) Q) 0) ® O 0) 0) 01 0> 0) 0> 01 o Q .aa a a a cL Q .a Q .Q .aQ .a a EEEEEEEEEEEEEEE C O C O C O C O C O C C I C O Q I C O C Q C O C O C D C O C p OTOTOTOTOTOTOTOTOTCOOTOTOTOTOT in i d s co oi o »- » - T - T - T - T - CM CM a co in cp. s n a g CM CM CM CM CM CM CM ooodoodsoodosoq Q . 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TABLE B2 !d S In d r r i S S U ) ( 0 C 5 Q Q N C p 0 ) C M O © ( 0 O 0 ) f M ( D S 0 ) C 0 f f lC 5 * 0 ^ C N |Q r P ) 0 ) l ( t O ( O t O I > O t - t ' - O I O > N N i - r { 0 ® 0 0 ) n i n O O ® oocjjT^d^t^oiaj^cvioo^cpoio^cpcp'^o^cptN oqj § »-r-scsiooNM in®m i^T-NO)inininNr-g)*-soN't(5inT-o S ^ O O N O t r O « » r - O n < » r ^ S T - ( O n ( D O N k S O « r r c?d 7 9 d ^ 9 ? 7 7 9 7 6 d 9 7 9 ^ 9 9 9 9 9 9 9 ? ^ ° V i - n i o c i n s i o i o o i o t D o n n s s f f i o t n M s g N io « s r Io s iiii-v n o ® < » ( 0 ® q«r( 5 » -^ N o dsdiriN njW N iooiQ ^S T -W aiviirinin^^fficd CO r«- coN8 COCMCMCMVCOCMCMCO CM CO CM CO ddcotfjO-^-opcdiO CO'OCOCOCOCOCOCMCO 8 8 8 o> ai co ^ cvi CM CM CO CO O’ CM CO M IO t o S QJ O 0) Q) Q) 0 ^ a& Q .Q .o.Q .aa.Q .Q . EEEEEEEEEE 0 » *C M C O M > 0 (O S GO OJ *— ^— *— T— T- T* *— co o> o «- T- r - CM CM CO O’ co CM CM CM n co g> o CM CM C4 CO 00011)0)901)4)04)9000414(10 Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q.Q-Q.Q.QJ EEEEEEEEEEEEEEEEEEE a. C B C Q C D C D C Q C O C O C O C Q C D C U C O C O C O C D C O C O C O C V C O C O C O C O C U C O C O C D C U C Q C p O)COO9COCOCOO9COCOCOCOCO<»COCOCOC/}COCOCOC/)COCOCOWCO(OCOCO09 GOo K N r)--® tr-s5noo)Q ® cococoinni ( N N ^ ( 0 0 ( D N O ( D r t N I D O O ( f l i n > - ( 0 > - cbdcoc^T-^cpcodocodco^cococo^cp ° CO s «n co CO CO CM CM CO TCO 00 n- a> o a> co t- o n- o coO CO CO Qr CM S IO N M N O O N i-m O n n O W n M ’ MNSIOStOJQCfQiPS® ® C N C M » - i i ) N ^ ( J ) O N » - O O T - ^ C ) » - » - O C O O O ^ » - 0 ® C M M O i - ® 9 9 v 9 ° 7 9 9 9 d 9 d 9 7 " 6 9 d 7 9 9 9 v 9 ^ d 'li 7 V 9 9 mcosr-comcnoiPJoiinajooiOQcccMcocoinco^coT-oiQincM^ o s o x D M o o o m c o i n c M N '- in c c o s o x o o c p ip in T - s c p in q iD O ) ebcboidtptoaicMcbuidco^cMcb^^dcotdotoiddcMaidcoujd CMCO t-CMCMCOCMCOCMCOCOCOCOCOCMCOCOCOCOCOCMCMCOCMCOCMCO^COCO 8 CO CM CO V U) CD S T— CM COco<irin(DS(DO)0»-oj(OM'io(Dscoo>o n i ' i N » / < u i ' - » u i « ' - > - ' - |r r ' t - T ' r - r i - ( M C M ( M ( M N ( M ( M ( M 0 l ( M ( 0 ea>a>oa>a>a>a>a>a>a)a>a>a>a>a>a>a>a>a>a>a>a>a>a>a>a>a>a> "n c i ~a q q o o o n o o n Q . a Q . Q . Q . Q . a Q . a Q . a Q . Q . a Q . Q . Q O GO CD T - a o . a a a a a a a a o . a ______________________________________ EEEEEEEEEEEEEEEEEEEEEEEEEEEEE ( 0 (0 (0 C Q ( Q C Q C Q ( Q ( 0 C9 (0 ( 0 C0 ( Q ( Q ( Q C 0 ( Q ( Q ( D C 0 C0 ( Q ( 0 ( Q C u v Q ( Q C 0 wcowcococowojtocowcowcoc/xowqacomnwcowcoaxoaaco Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B3 §183 n n in to » o 1^. CO CO CO CO m (D (n m S soornspiinQ S © t^ « o a ( D U ) v o i i n t ! S N i - i o ^ r o C O C O C O M r O O O C O f l O O O l O 0 0 0 ^ 9 0 - ^ 9 9 ^ 0 r f m — CM — o m io tn o in n jN inM- f'- ° 7 9 9 9 t 9 9 ttt- CM S s (J) CM n n 01 ^ 9 T 9 hco sopinopiDV'-nQQipirxtooNi-tMncMipr-T-mcMOtr'eotC <-3T?OONCOO(DTCM7CMinO)COi-(DnODinSCMCM(D(Mn(OOi ^ co co co in ^ n eg n n N ic Q Q O )'tm iD C !)0 )in o ro Q (o c )Q in o (D iD io g g q ) c M P > n ? n n c M « n N rtrtn in M F ^ ? M f5 n n (o n n n 8 o P I W ^ i n i O S f f l B r - r - t - r T - T - r r " OQOQOfflOVIDSIDtllDVOt) a a a a a a Q . a a Q . a Q . a a a a EEEEEEEEEEEEEEEE ( p S 0 0 O ) O CM CM CM CM CO ( Q C B C O C O C D C D C D C D C O C D C D C O C O C D C Q C O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C O C O (MO'TmioswooT-tMOcnn f - T - T - r - « - T - T - T - { \ | C M C M ( N C M ( M © ® © O O © © © © © © © © ao.aaaaaaaaa.aal EEEEEEEEEEEEE C O C U C O C O C D C O C O C D C O C D C D C D C D C O C O C O C O C O C O C O C O C O C O C O C O C O o>o CM CM g) in CO Ml- d 0 - 9 cn cm in CO 1^ CO o $ oo m co co o- \># I I I M— y^j 1— vu \ ^ w 1— \ ' / \ >f l^» M l U l w V>| l IV W w ' I I MT O — CO CM N - •Mr9 ^ - c N i — — ociicNicMiri — 9 d c \ i 9 MrcMco — 9 c o 9 - s n M n c N i o o o i i n r - o o s s - c o i n c n c o c M — r o c o c o — c M c n r o : d d c M b ^ ‘ cMco — o c o d c M —: s S cO CD co — i f 0>(M( 0 S ( 0 T-( 0 (3 ® » -® 00in o ( M 0)CM( 0 in | n 0 ) 3 i- r - ’?tt(0<Oi-MninCMinSO(DO)COOCMCMOCM(ONOT-OCM^^^ <=>9 v 9 9 9 v 9 9 ° y 9 9 \ ;9 9 9 9 9 9 9 9 v c> V v 9 y 9 9 ft! O ) CMCOCOCOCDCnCOCMinOinCMQCOCO r « i n C D ( 5 i f O N T - ( M ( D C M O ) ® S oo o> cd o ~ CO CM CM CO l$W8 S O) O) — - . f f l O S M r- m t o CO CM CM ’t co co in ro CO CO CO CM o in CO CM O ) CO O ) o p 00 CO CO CO ^ CM S 8 8 3 8 3 S — ro — r - co mi CO CM ^ M n CM CO C O — cm co m - in co r*- 00 o> — CM CO ^ lO (O N row o — 1- CM CMa coMiniDNoomo IM I ' l ^ H I l i l 1^. u i U l ”— 1— M— M— M— M— 1— M M— » IN IM \ M IM I M V M VM IM % M I I CMCMCMCMCMCMCMCO ©©©© ©©©©©© ©©©©©©©©©©©©©©©©©©© aaaaaagaaaaaaaaaaaaaaaaaaaaaQ _________ aaaaaaaaaaaaaaaaaa EEEEEEEEEEEEEEEEEEEEEEEEEEEEE COCOCOCOCQCOCOCOCOCQCOIOCOCOCOCOCOCQCOCOCOCOCOCOCOCaCOCOCO cococncncncncocncncocncncncncncncncncncncncocncncocncococo a . E Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B4 ARGON DAY 14 L a b Sample 1 40.63 -1.32 -4.94 Sample 2 41.52 -0.98 -2.96 Sample 3 42.90 -0.45 -5.29 Sample 4 32.19 -0.47 -3.37 Sample 5 29.96 -0.68 0.00 Sample 6 32.55 0.06 -2.27 Sample 7 37.03 -0.61 -4.04 Sample 8 37.48 -0.82 -4.03 Sample 9 35.31 -1.14 -2.71 Sample 10 37.24 -1.19 -1.59 Sample 11 29.16 -0.51 -3.23 Sample 12 29.31 0.01 -2.85 Sample 13 20.79 -0.59 0.16 Sample 14 34.97 -0.40 -6.17 Sample 15 35.91 -0.37 -3.47 Sample 16 26.59 -1.16 1.45 Sample 17 31.30 0.12 -1.96 Sample 18 42.32 -2.08 -5.40 Sample 19 38.80 -1.01 -3.06 Sample 20 37.61 0.15 -4.29 Sample 21 42.88 -2.89 -2.80 Sample 22 27.27 -1.71 0.94 Sample 23 37.90 -2.45 -2.51 Sample 24 32.87 0.07 -2.15 Sample 25 33.42 -0.63 -3.99 Sample 26 33.59 -0.02 -3.55 Sample 27 28.83 -1.10 -0.15 Sample 28 38.91 -1.46 -3.53 Sample 29 30.50 -1.51 -0.61 Sample 30 39.56 -1.99 -4.42 MEAN 34.64 -2.76 ARGON DAY 28 L a b Sample 1 44.89 -1.32 -5.74 Sample 2 42.01 -0.39 -4.76 Sample 3 34.73 0.48 -5.13 Sample 4 38.96 -1.15 -3.84 Sample 5 24.51 -0.45 -0.01 Sample 6 35.50 -0.40 -2.43 Sample 7 34.61 0.55 -3.96 Sample 8 36.17 -0.89 -3.72 Sample 9 31.53 -0.43 -1.72 Sample 10 30.08 0.32 -2.15 Sample 11 22.99 -0.53 -1.00 Sample 12 24.95 -0.22 -1.87 Sample 13 24.88 -0.71 -1.06 Sample 14 38.18 -1.05 -5.97 Sample 15 29.09 -0.53 -1.59 Sample 16 31.25 0.11 -1.11 Sample 17 35.81 -1.17 -2.52 Sample 18 36.08 -1.36 -3.63 Sample 19 40.17 -0.73 -3.63 Sample 20 40.97 -0.77 -5.20 Sample 21 44.70 -2.39 -4.01 Sample 22 27.38 -2.00 1.56 Sample 23 33.31 0.65 -3.89 Sample 24 34.45 -0.15 -2.26 Sample 25 28.76 -0.20 -3.24 Sample 26 38.76 -0.65 -4.69 Sample 27 30.31 -0.59 -0.37 Sample 28 36.02 -0.47 -3.73 Sample 29 30.09 -0.51 -1.27 Sample 30 38.72 -0.94 -5.32 MEAN 34.00 -0.60 -2.94 110 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B5 XENON DAY0 L a b Sample 1 26.83 -0.62 0.60 Sample 2 37.21 -2.25 -0.10 Sample 3 37.18 -1.00 0.50 Sample 4 41.60 0.01 -2.99 Sample 5 45.29 -3.66 1.37 Sample 6 36.09 -3.69 1.80 Sample 7 35.09 -2.17 0.85 Sample 8 29.18 -1.44 2.77 Sample 9 40.89 -1.09 -2.05 Sample 10 32.82 0.01 1.31 Sample 11 22.15 -0.58 5.32 Sample 12 26.51 -0.96 2.98 Sample 13 27.51 0.00 -0.39 Sample 14 46.01 -1.16 -0.78 Sample 15 46.60 0.06 -2.06 Sample 16 30.53 0.47 0.85 Sample 17 33.70 -1.87 7.36 Sample 18 34.07 -1.35 -0.07 Sample 19 51.56 -4.10 1.24 Sample 20 41.59 -4.28 2.04 Sample 21 48.95 -2.70 4.78 Sample 22 40.74 -0.23 -0.76 Sample 23 51.44 -2.17 -0.68 Sample 24 38.92 -2.82 4.78 Sample 25 51.06 -2.51 -0.42 Sample 26 42.85 -1.77 4.09 Sample 27 38.28 -1.68 4.93 Sample 28 44.17 0.85 -2.60 Sample 29 34.06 -0.74 0.79 Sample 30 42.52 -2.78 1.99 MEAN 38.51 -1.54 1.25 XENON DAY 1 L a b Sample 1 33.33 -0.19 -3.70 Sample 2 39.42 -0.08 -2.77 Sample 3 36.97 -0.99 -2.02 Sample 4 48.33 -2.35 -5.40 Sample 5 48.28 -3.94 -4.43 Sample 6 58.16 -3.21 -3.64 Sample 7 38.68 -1.24 -2.12 Sample 8 30.82 -0.09 -0.27 Sample 9 41.14 -2.41 -3.42 Sample 10 28.38 0.36 -0.96 Sample 11 23.58 -0.72 2.95 Sample 12 26.70 -1.39 -0.43 Sample 13 25.08 -1.40 -1.25 Sample 14 45.78 -2.87 -3.62 Sample 15 38.42 0.48 -2.96 Sample 16 48.15 -2.28 -3.25 Sample 17 39.51 -0.94 1.86 Sample 18 34.64 -1.87 -2.94 Sample 19 48.97 -0.99 -2.12 Sample 20 51.82 -3.82 -3.31 Sample 21 58.16 -2.44 -4.99 Sample 22 44.59 -2.30 -3.13 Sample 23 53.96 -2.35 -3.39 Sample 24 42.38 -1.25 -0.51 Sample 25 53.14 -2.42 -3.73 Sample 26 42.01 -3.04 0.50 Sample 27 35.99 -2.16 -1.58 Sample 28 52.14 -0.01 -4.87 Sample 29 36.10 -1.64 -1.28 Sample 30 49.44 -3.01 -2.58 MEAN 41.80 -1.69 -2.31 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B6 XENON DAY 14 L a ft Sample 1 25.78 -0.44 -1.51 Sample 2 35.34 -1.09 -2.28 Sample 3 39.32 -0.84 -3.08 Sample 4 46.41 -2.36 -5.33 Sample 5 51.12 -0.98 -5.10 Sample 6 60.07 -0.86 -4.10 Sample 7 34.37 -1.48 -1.73 Sample 8 31.17 -0.27 0.45 Sample 9 42.15 -1.17 -4.79 Sample 10 34.14 -1.19 -1.02 Sample 11 24.99 -1.03 2.33 Sample 12 26.33 -0.48 -0.43 Sample 13 39.01 -0.32 -5.30 Sample 14 44.02 -1.88 -3.14 Sample 15 44.80 -2.28 -4.82 Sample 16 45.51 0.64 -3.42 Sample 17 37.25 -1.06 2.72 Sample 18 35.51 -1.14 -2.99 Sample 19 35.27 -1.09 -1.04 Sample 20 37.61 -2.40 -1.15 Sample 21 54.55 -1.06 -3.93 Sample 22 39.26 -2.23 -1.31 Sample 23 48.94 -1.64 -3.07 Sample 24 39.56 -1.10 0.90 Sample 25 50.20 -1.90 -3.76 Sample 26 42.53 •0.89 -1.10 Sample 27 37.15 -0.02 -0.03 Sample 28 40.77 -1.70 0.48 Sample 29 32.99 -0.33 -1.01 Sample 30 42.52 -2.08 -4.30 MEAN 39.95 -1.16 -2.10 XENON DAY 28 L a b Sample 1 26.44 -1.41 -0.81 Sample 2 39.26 -0.39 -2.45 Sample 3 38.04 -0.30 -2.91 Sample 4 45.16 -0.31 -5.54 Sample 5 44.77 0.66 -3.95 Sample 6 60.70 -2.13 -3.62 Sample 7 34.81 -0.41 -2.03 Sample 8 32.66 -1.03 0.68 Sample 9 36.56 -0.05 -3.59 Sample 10 32.38 0.35 -1.60 Sample 11 24.91 -0.18 3.55 Sample 12 25.88 -0.11 -0.92 Sample 13 39.22 -0.20 -5.15 Sample 14 44.69 -1.61 -2.43 Sample 15 32.50 -2.66 -3.33 Sample 16 47.24 -0.35 -3.65 Sample 17 36.09 0.02 1.82 Sample 18 34.55 -0.24 -2.63 Sample 19 54.74 -0.23 -2.87 Sample 20 51.71 -1.23 -3.47 Sample 21 53.98 -1.04 -2.12 Sample 22 38.10 -1.61 -1.37 Sample 23 43.71 -0.78 -3.13 Sample 24 36.92 0.41 -0.47 Sample 25 48.63 -0.57 -4.20 Sample 26 45.44 -1.19 -1.51 Sample 27 37.99 -1.38 0.03 Sample 28 45.16 0.86 -4.58 Sample 29 35.67 -0.69 -1.17 Sample 30 44.15 -1.29 -1.73 MEAN 40.40 -0.64 -2.17 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B7 P < C i - ( M t O ) O n O U ) i n n i D Q O ) ( O I D N t O I D I D . . i© o n O N « (N o n n in o ® n n ^ -» -tm N © N s ^ c m '!rcNi'<j-rocp'^-TfCNi^cprororocNcoocpO'r|-cO'r- cp c i ^ co oi tom rr <9 co «(DT-»CO?®l5<DO(OOpO»nQ<M(OfflONT-*<t(nOffl«)«-»-(M ^ rt(N ^ '-t6 n ifi» -n in (D < N n in T -i5 ifir-(N T rin (N N (N O )'-N N tfi o 9 9 ^ ? 9 ^ V ^ 9 9 7 7 7 ^ T v n 9 7 ° 'l i(l ' 9 9 9 v 9 8 rnnnoiAiooog CO ( O f M r r - s ( D O ) o a ) Q a d T rN Q ffldN m adiA Q oiffflujN aioQ btovgiaiaiaialf r t n M ^ v n n n n n n n v v v n n ^ n n r t v r t v N ^ w n p ) ^ O- Ttt a> N M O) S (O f ONOONID SU)SONC00)(Dtf) CO8 >. §I O f i N n ^ i n i o s t o o O f N n ^ u x D S c o g t g fCin«IO<ONfl0O)fffffffffflM CM NCNCM CM NNCM N(O O0lll)O 4)O 4)OO OVQIW 4IIDIDtt(DOQ )ID<DO IDC)O C4)IDIII Q . a Q . a a a a a a a a a a a a a a a a a Q . a Q . Q . Q . a a. a. a. ex EEEEEEEEEEEEEEEEEEEEEEEEEEEEEE ( 0 Q ( D ( D Q ( 0 f l ( D < D ( 0 Q ( 0 (0 f l w ( Q ( D ( O ( 0 Q Q ) ( O Q ( 0 lOC 0 i B ( O ( O i D c o cacocacacocococococacocacocococaco ca coco co coco co a? co co co co CO 8 3 o eg s i o ^ f C M o o i O N - n ’t f m o s o i ^ f i n N o o ^ Q f f C O f f n o s n m in o fio n r tM n o a o ffln 'B r tin io o K O ^ ' ~ ^ O f O f O < i i o ( O f 9 9 9 i n n i n f c g f C O m CT) 04 O ooNioodo inNcinoifntfVSiOfNNfflogoxooiNtDffWfiQoo ( N » f f ^ N O m N C J I D ^ C I ) f f i n f ( N i n M O n ® S ) ( D C 4 ( N N O S N odr-CNjcjicjidcpcpcpcjicpcpoicpoidr-PdciidQTrCNidptVQQ 8 9 9 9 V 9 9 9 9 9 9 CO o> in inCN 8 C 4 C \|IO (0 (D Q )(N f(O ^ (D fC 4 fC )5 ^ N f0 0 O )in tD lO 3 n a )® 'TNfC'l(50)fniO'CN'Cin(D<naiONfN^(N(DfOOBfflN fO iQ in co v n o fflfn cD M n o iftO fO xo o ) c m c o ^ F c m c m c m c o c o c m c O ' M - c m c m c o c m c o c o c o c o c o c o in f in • V CM CO X CD CO CO at 8 S 8 0) O fP in g in iD M D O iO fN n t in f flM D O i c m g i n B S f f l O l f f f f f f f f f f N N N N C N C K M N C N C N g O f f i C O O C C O l O O C O O C I D O O O O O l l D O O t l Q f f i O a a a a a a a a a a a a a a a a a a a a a a a a a a a a d EEEEEEEEEEEEEEEEEEEEEEEEEEEEE C Q C Q f l l C D C O C Q C Q C O f l J C O C O C O C Q C O C Q C Q I Q C D C Q C Q C Q C Q C D C O C D C O C Q C Q C U W W W W W W W W M C O W W W W C D W W W W W C O W W W W W W W W Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B8 7/HAL DAY 14 L a b Sample 1 31.15 0.49 -0.75 Sample 2 34.75 -0.24 -0.94 Sample 3 25.60 -0.90 3.79 Sample 4 39.68 -1.56 -1.92 Sample 5 41.26 -0.30 -4.88 Sample 6 37.79 -0.30 -4.30 Sample 7 36.74 -0.79 -0.71 Sample 8 31.06 -1.43 -1.31 Sample 9 34.30 -0.70 -3.70 Sample 10 38.44 -1.82 -2.23 Sample 11 28.43 -0.36 3.41 Sample 12 39.50 -1.94 -0.79 Sample 13 44.55 -1.01 -1.89 Sample 14 44.14 -1.72 -4.00 Sample 15 39.94 -1.84 -2.68 Sample 16 37.18 -0.89 -0.63 Sample 17 38.55 -1.24 0.62 Sample 18 34.60 -2.54 2.12 Sample 19 35.10 -0.07 -1.45 Sample 20 29.51 -0.46 -0.47 Sample 21 41.90 -2.34 -2.54 Sample 22 30.86 -0.14 1.89 Sample 23 40.41 0.05 -0.95 Sample 24 45.31 -2.81 -1.49 Sample 25 25.69 -1.47 2.14 Sample 26 50.29 -1.32 -5.17 Sample 27 40.58 -1.98 0.48 Sample 28 42.28 -2.43 -3.37 Sample 29 38.33 -2.09 -1.77 Sample 30 37.68 0.30 -3.83 MEAN 37.19 -1.13 -1.24 7/HAL DAY 28 L a b Sample 1 31.24 0.13 0.39 Sample 2 37.13 -1.16 -2.00 Sample 3 28.24 -0.81 3.72 Sample 4 34.68 0.18 -2.71 Sample 5 41.63 -0.52 -5.16 Sample 6 38.35 -1.04 -5.29 Sample 7 34.28 -0.28 -0.46 Sample 8 32.38 -2.16 -1.40 Sample 9 37.00 -2.09 -4.32 Sample 10 38.18 -1.39 -1.61 Sample 11 29.49 -0.46 3.74 Sample 12 39.72 -1.04 -1.14 Sample 13 40.49 -0.30 -2.28 Sample 14 47.18 -1.44 -4.89 Sample 15 39.32 -1.23 -4.50 Sample 16 32.90 -0.90 -0.45 Sample 17 37.71 -1.35 1.32 Sample 18 35.07 -2.34 0.96 Sample 19 29.26 0.09 -1.07 Sample 20 31.53 -0.37 -0.71 Sample 21 31.98 0.47 -2.20 Sample 22 34.45 0.32 0.92 Sample 23 40.84 0.20 -1.27 Sample 24 44.41 -1.53 -1.29 Sample 25 32.27 -1.35 0.51 Sample 26 49.10 -2.19 -4.65 Sample 27 34.17 -1.66 2.37 Sample 28 42.23 -1.55 -3.53 Sample 29 35.66 -1.77 -1.01 Sample 30 39.90 -2.38 -2.58 MEAN 36.69 -1.00 -1.35 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B9 SAUNE: DAY 0 - DAY 1 SAUNE: DAY0-DAY14 SALINE: D A Y0- DAY 28 AL* AA* Ab* AE* AL* AN* Ab* AE* AL* Aa* Ab* AE* 1 5.51 -0.93 2.33 6.08 0.79 -0.51 3.03 3.17 -1.05 •0.33 1.33 1.73 2 1.89 -0.25 0.50 1.97 2.10 -1.46 0.71 2.65 3.22 -0.10 0.00 322 3 2.59 0.21 1.01 2.79 1.56 0.76 -1.08 2.04 1.93 0.91 -1.16 2.43 4 -4.11 -2.11 -1.28 4.79 -6.00 •0.04 -0.52 6.02 -10.11 0.18 -1.68 10.25 5 •4.62 -0.14 -1.34 4.81 -626 0.52 -1.42 8.40 -7.47 0.63 -1.83 7.72 e 4.14 -2.49 0.46 4.88 0.72 -1.02 0.66 1.41 7.66 -1.51 -0.12 7.81 7 1.60 0.51 0.41 1.73 •0.92 0.11 0.02 0.93 0.96 0.48 -1.54 1.88 8 2.06 -1.66 1.97 3.30 3.44 0.20 -0.80 3.54 -1.60 0.52 -1.47 223 9 -1.07 0.48 -1.96 2.28 3.87 1.34 -3.30 5.26 2.73 1.16 -2.79 4.07 10 -10.23 •0.05 -1.65 10.36 •2.94 0.29 -1.38 3.26 0.95 -1.66 -0.04 1.91 11 -7.31 1.65 -2.97 8.06 -6.46 1.27 -3.53 7.47 1.64 0.63 -1.08 2.06 12 5.63 0.10 0.45 5.68 •0.22 0.52 •0.40 0.69 10.58 -0.75 -0.59 10.62 13 -6.40 1.53 0.07 6.88 -3.91 0.38 0.09 3.93 -7.05 1.52 -1.82 7.44 14 1.18 0.30 0.07 1.22 5.20 •0.90 0.41 5.29 4.54 0.65 -0.60 4.63 18 2.57 -0.31 0.02 2.89 -0.62 2.32 0.15 2.41 -4.19 0.34 0.86 429 16 -6.06 1.70 0.67 6.33 -7.30 1.89 0.39 7.55 -1.33 0.41 0.29 1.42 17 1.22 -1.58 0.41 2.04 -4.53 0.23 -1.01 4.65 -025 •0.08 -0.92 0.96 18 -4.56 1.07 •0.81 4.75 -2.14 0.71 -1.91 2.95 3.30 -2.18 -1.90 4.39 19 7.57 -1.49 3.06 8.30 6.29 -0.84 1.97 6.64 5.84 -0.94 1.19 6.03 20 -0.72 1.48 -0.53 1.73 0.32 1.35 -0.64 1.62 0.93 0.88 -1.56 2.02 21 -0.79 -0.03 0.59 0.99 -3.44 0.79 -044 3.56 1.04 0.75 -0.59 1.41 22 0.99 0.34 •0.64 1.23 -1.98 129 2.13 3.18 -024 1.12 -1.94 2.25 23 7.65 -1.45 0.86 7.83 10.48 -126 0.05 10.56 9.21 -020 -1.53 9.34 24 •0.46 0.42 -0.50 0.80 -0.20 0.51 -3.95 3.99 -1.38 0.35 -2.92 3.25 28 -3.97 0.29 0.09 3.98 -1.97 -4.45 9.45 10.63 1.05 1.58 -0.65 2.01 26 -1.28 -0.01 -0.22 1.30 0.72 2.48 -0.65 2.66 0.44 1.50 •3.00 3.36 27 5.10 2.56 -0.72 5.75 -3.73 0.67 3.03 4.85 -4.73 3.04 -1.10 5.73 28 -1.97 0.41 -0.28 2.03 0.36 -0.31 0.32 0.57 -9.37 -1.90 -0.85 9.60 29 0.91 1.31 -0.75 1.76 3.57 1.24 -0.02 3.78 2.74 2.52 -0.85 3.82 30 -3.21 0.08 0.52 3.25 -7.02 0.51 0.04 7.04 -1.43 0.37 -0.44 1.54 MEAN -0.21 0.06 9 o 0.22 -0.74 0.29 0.04 0.80 029 0.33 -0.98 1.07 115 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE BIO ARGON: DAY 0 - DAY 1 ARGON: DAY 0 - DAY 14 ARGON: DAY 0 - DAY 28 aL* AO* A b* aE* A L* AN* A b* aE* aL* AO* Ab* aE* 1 8.13 0.40 -6.34 10.32 1.59 -1.38 -5.36 5.75 5.85 -1.36 •6.16 8.60 2 -1.72 1.04 -5.05 S.44 3.12 -0.52 -3.98 5.08 3.61 0.07 -5.78 6.82 3 -13.05 2.34 -2.03 13.41 1.40 1.51 -4.79 521 -6.77 2.44 -4.63 8.56 4 14.59 -1.03 -7.65 16.51 0.30 0.16 •5.32 5.33 7.07 •0.52 -5.79 9.15 5 9.97 -0.54 -5.57 11.43 4.87 -0.37 -4.23 6.46 -0.58 -0.14 •4.24 4.28 6 2.33 0.60 0.16 2.41 7.84 0.20 -1.76 8.04 10.79 -0.26 -1.92 10.96 7 -3.71 2.81 -1.37 4.88 -3.39 1.18 -2.88 4.60 -5.81 2.34 -2.80 6.86 8 6.97 -1.33 -5.67 9.08 3.62 -0.30 -5.10 6.26 2.31 -0.37 -4.79 5.33 9 6.47 -0.11 -5.35 8.40 1.78 -0.61 -4.89 5.24 -2.00 0.10 -3.90 4.38 10 3.67 -1.12 -5.39 6.62 1.31 -1.46 •3.45 3.97 -5.85 0.05 -4.01 7.09 11 5.78 0.51 •4.88 7.88 0.48 1.02 -4.43 4.57 -5.69 1.00 -2.20 6.18 12 -5.24 0.72 -1.71 5.86 -1.18 0.72 -3.33 3.61 -5.54 0.49 -2.35 6.04 13 11.38 -1.53 -5.58 12.77 ■427 -0.56 -1.89 4.70 -0.18 •0.68 -3.11 3.19 14 0.56 1.97 -2.86 3.52 -3.75 1.43 -3.99 5.66 -0.54 0.78 -3.79 3.91 IS 0.42 •0.25 -2.80 2.84 6.76 0.62 -5.80 8.93 -0.06 0.46 -3.92 3.95 16 9.71 0.16 -6.52 11.70 0.39 •0.85 -3.79 3.90 5.05 0.42 -6.35 8.12 17 7.97 -0.12 •4.63 9.22 0.45 0.20 -3.67 3.70 4.96 -1.09 -4.23 6.61 18 -0.09 1.36 -2.80 3.11 3.10 0.20 -4.73 5.66 -3.14 0.92 -2.96 4.41 19 16.92 -0.91 -5.35 17.77 4.90 -0.76 -3.59 6.12 6.27 -0.48 -4.16 7.54 20 8.40 2.63 -2.18 9.07 -2.25 3.23 -1.32 4.15 1.11 2.31 -2.23 3.40 21 -4.97 2.83 -3.25 6.58 -5.90 0.33 -2.15 6.29 -4.08 0.83 -3.36 5.35 22 12.40 -0.84 -6.26 13.92 -0.84 -1.02 -328 3.54 -0.73 -1.31 -2.66 3.05 23 8.92 0.10 -6.45 11.01 1.04 -0.73 -4.67 4.84 -3.55 2.37 •6.05 7.40 24 8.52 -1.20 -6.34 10.69 1.17 0.04 -5.95 6.06 2.75 -0.18 -6.06 6.66 28 7.90 -1.30 -5.83 9.90 5.12 0.52 -5.68 7.66 0.46 0.95 -4.93 5.04 26 5.64 -0.66 -3.81 6.84 -7.41 1.03 -2.90 8.02 -2.24 0.40 -4.04 4.64 27 •6.37 1.33 -3.04 7.18 -12.81 -0.81 -3.26 13.24 -11.33 •0.30 •3.48 11.86 28 0.88 1.10 -3.54 3.81 0.41 -0.02 -325 3.28 -2.48 0.97 -3.45 4.36 29 3.00 -0.98 -3.16 4.47 2.86 -1.10 -3.55 4.69 2.45 -0.10 -4.21 4.87 30 4.14 -0.51 -3.26 8.29 3.74 -1.58 -2.55 4.79 2.90 -0.53 -3.45 4.54 MEAN 4.32 0.25 -4.28 6.09 0.48 0.01 -3.85 3.88 •0.17 0.32 -4.03 4.05 116 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B11 XENON: DAY 0 - DAY 1 XENON: DAY 0 - DAY 14 XENON: DAY 0 - DAY 26 AL* AO* Ab* aE* aL* AM* Ab* aE* aL* AE* Ab* aE* 1 8.50 0.43 -4.30 7.81 -1.05 0.18 -2.11 2.36 -0.39 -0.79 -1.41 1.66 2 2.21 2.17 -2.67 4.09 -1.87 1.16 •2.18 3.10 2.05 1.86 -2.35 3.63 3 -0.21 0.01 -2.52 2.53 2.14 0.16 -3.58 4.17 0.86 0.70 -3.41 3.59 4 6.73 -2.36 -2.41 7.53 4.81 -2.37 -2.34 5.65 3.56 -0.32 -2.55 4.39 5 2.99 •0.28 -5.80 6.53 5.83 2.68 -6.47 9.11 -0.52 4.32 -5.32 6.87 • 22.07 0.48 -5.44 22.74 23.98 2.83 •5.90 24.86 24.81 1.56 -5.42 25.25 7 3.59 0.93 -2.97 4.75 -0.72 0.69 -2.58 2.77 •0.28 1.76 -2.88 3.39 3 1.64 1.35 •3.04 3.71 1.99 1.17 -2.32 3.27 3.48 0.41 -2.09 4.08 • 0.25 -1.32 -1.37 1.92 1.26 •0.08 -2.74 3.02 -4.33 1.04 -1.54 4.71 10 -4.44 0.35 -2.27 5.00 1.32 -1.20 -2.33 2.93 -0.44 0.34 -2.91 2.96 11 1.43 -0.14 -2.37 2.77 2.84 -0.45 -2.90 4.15 2.76 0.40 -1.77 3.30 12 0.19 •0.43 -3.41 3.44 •0.18 0.48 -3.41 3.45 -0.63 0.85 •3.90 4.04 13 -2.43 -1.40 -0.86 2.93 11.50 -0.32 •4.91 12.51 11.71 -0.20 -4.78 12.64 14 -0.23 -1.71 -2.84 3.32 -1.99 -0.72 -2.36 3.17 -1.32 -0.45 -1.65 2.16 15 -8.18 0.42 -0.90 6.24 -1.80 -2.34 -2.76 4.04 -14.10 -2.72 -1.27 14.42 16 17.82 -2.75 -4.10 18.30 14.98 0.17 -4.27 15.56 16.71 •0.82 •4.50 17.32 17 5.81 0.93 -5.50 8.05 3.55 0.81 -4.64 5.90 2.39 1.89 -5.54 6.32 16 0.57 -0.52 -2.87 2.97 1.44 0.21 •2.92 3.26 0.48 1.11 -2.56 2.83 19 -2.59 3.11 -3.36 5.26 -16.29 3.01 -2.28 16.72 3.18 3.87 -4.11 6.46 20 10.23 0.46 -5.35 11.55 -3.98 1.88 -3.19 5.44 10.12 3.05 -5.51 11.92 21 9.21 0.26 -9.77 13.43 5.60 1.64 -8.71 10.46 5.03 1.66 -6.90 8.70 22 3.85 -2.07 -2.37 4.97 -1.48 -2.00 -0.55 2.66 -2.64 -1.38 -0.61 3.04 23 2.52 -0.18 -2.71 3.70 •2.50 0.53 -2.39 3J0 -7.73 1.39 -2.45 8.23 24 3.46 1.57 -5.29 6.51 0.64 1.72 •3.88 4.29 -2.00 3.23 -5.25 6.46 25 2.08 0.09 -3.31 3.91 -0.86 0.61 -3.34 3.50 •2.43 1.94 -3.78 4.89 26 -0.84 -1.27 -3.59 3.90 -0.32 0.88 -5.19 5.27 2.59 0.58 -5.60 6.20 27 -2.29 -0.48 -6.51 6.92 -1.13 1.66 •4.96 5.36 -0.29 0.30 -4.90 4.92 26 7.97 -0.86 -2.27 8.33 -3.40 -2.55 3.08 5.25 0.99 0.01 -1.98 2.21 29 2.04 -0.90 -2.07 3.04 -1.07 0.41 -1.80 2.13 1.81 0.05 -1.96 2.54 30 6.92 -0.23 -4.57 8.30 0.00 0.70 •6.29 6.33 1.63 1.49 -3.72 4.33 MEAN 3.29 -0.14 -3.56 4.65 1.44 0.39 -3.34 3.66 1.89 0.90 -3.42 4.01 117 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B12 T/HALOGEN: DAY 0 • DAY 1 AL* A«* Ab* aE* T/HALOGEN: DAY 0 - DAY 14 AL* A8* Ab* AE* T/HALOGEN: DAY 0 - DAY 28 AL* A8* Ab* AE* 1 13.10 021 •1.49 13.19 5.64 0.24 -0.84 5.71 5.73 -0.12 0.30 5.74 2 1.96 0.51 -5.10 5.49 -1.42 0.63 -3.38 3.72 0.96 •0.29 •4.44 4.55 3 3.31 0.91 0.44 3.46 4.18 0.22 -0.58 4.23 6.82 0.31 -0.65 6.86 4 3.21 -0.31 -3.17 4.52 0.46 0.62 -2.77 2.88 -4.54 2.36 -3.56 6.23 5 -0.05 0.36 •2.30 2.33 1.11 0.19 -3.14 3.34 1.48 •0.03 -3.42 3.73 6 11.49 0.07 -3.60 12.04 12.53 0.41 -4.61 13.36 13.09 -0.33 -5.60 14.24 7 12.99 -242 -1.78 13.33 10.08 -0.82 -2.23 10.38 7.62 •0.31 -1.98 7.88 8 7.97 -1.04 -1.83 8.24 6.07 -0.89 -1.89 6.42 7.39 -1.62 -1.98 7.82 9 4.88 -1.45 -2.03 5.48 1.18 0.01 -1.65 2.03 3.88 -1.38 -2.27 4.70 10 9.49 -224 -2.62 10.10 8.13 -1.58 -2.40 8.62 7.87 -1.15 -1.78 8.15 11 1.57 0.26 -2.18 2.70 -0.13 0.48 -3.12 3.16 0.93 0.38 -2.79 2.97 12 4.03 -0.23 -1.97 4.49 8.06 -1.49 -2.23 8.49 8.28 -0.59 -2.58 8.69 13 5.15 -0.38 -2.66 5.81 0.79 -0.10 -1.51 1.71 -3.27 0.61 -1.90 3.83 14 19.86 0.84 -3.28 19.95 14.73 0.45 -3.30 15.10 17.77 0.73 -4.19 18.27 18 14.20 -1.38 -2.73 14.53 12.42 -1.72 -2.11 12.71 11.80 -1.11 -3.93 12.49 16 0.78 -0.61 -2.41 2.81 1.57 1.62 -5.63 6.07 -2.71 1.61 -5.45 6.30 17 5.54 -1.74 -0.69 5.85 9.02 -1.42 -3.25 9.69 8.18 -1.53 -2.55 8.70 18 10.25 -0.35 -5.75 11.78 2.62 -1.30 -3.79 4.79 3.09 -1.10 -4.95 5.94 19 4.07 -1.51 -2.27 4.90 -0.44 0.52 -3.30 3.37 -6.28 0.68 -2.92 6.96 20 3.27 -0.51 -1.88 3.81 -2.26 0.30 -2.89 3.68 -0.24 0.39 -3.13 3.16 21 -0.16 2.28 -2.58 3.45 2.79 0.35 -3.92 4.82 -7.13 3.16 -3.58 8.58 22 7.08 -1.86 -4.72 8.71 -2.92 -0.46 -6.49 7.13 0.67 0.00 -7.46 7.49 23 -3.79 0.88 -3.30 5.10 0.92 0.69 -2.49 2.74 1.35 0.84 -2.81 3.23 24 0.37 -0.87 -1.34 1.64 1.06 -0.93 -2.09 2.52 0.16 0.35 -1.89 1.93 28 -5.38 0.41 •0.44 5.41 -8.97 1.14 1.23 9.13 -2.39 1.26 -0.40 2.73 26 4.44 -0.78 -1.87 4.81 5.14 -1.11 -2.56 5.85 3.95 -1.98 -2.04 4.87 27 7.02 0.08 -2.26 7.38 19.54 -1.75 -4.95 20.23 13.13 -1.43 -3.06 13.56 28 3.23 2.00 -1.71 4.17 6.45 0.28 -2.46 6.91 6.40 1.16 -2.62 7.01 29 1.97 -0.86 -1.98 2.92 3.64 -1.24 -1.98 4.33 0.97 •0.92 -122 1.81 30 2.07 -0.24 -3.60 4.16 -2.10 0.58 -3.88 4.45 0.12 -2.10 -2.63 3.37 MEAN 5.12 -0.33 -2.43 5.88 4.00 -0.20 -2.81 4.89 3.50 -0.07 •2.92 4.56 118 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B13 SALINE L a b Day 0 33.07 -1.06 2.38 Day 1 32.87 -0.99 2.38 Day 14 32.33 -0.77 2.42 Day 28 33.36 -0.73 1.40 ARGON L a b Day 0 34.16 -0.92 1.09 Day 1 38.48 -0.67 -3.19 Day 14 34.64 -0.90 -2.76 Day 28 34.00 -0.60 -2.94 XENON L a b Day 0 38.51 -1.54 1.25 Day 1 41.80 -1.69 -2.31 Day 14 39.95 -1.16 -2.10 Day 28 40.40 -0.64 -2.17 T/HALOGEN L a b Day 0 33.19 -0.93 1.56 Day 1 38.31 -1.26 -0.87 Day 14 37.19 -1.13 -1.24 Day 28 36.69 -1.00 -1.35 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B14 DAY 0 - DAY 1 SALINE AL* -0.20 Aa* 0.07 Ab* 0.00 AE* 0.21 ARGON 4.32 0.25 -4.28 6.09 XENON 3.29 -0.15 -3.56 4.85 T/HALOGEN 5.12 -0.33 -2.43 5.68 DAY 0 - DAY 14 AL* Aa* Ab* AE* SALINE -0.74 0.29 0.04 0.80 ARGON 0.48 0.02 -3.85 3.88 XENON 1.44 0.38 -3.35 3.67 T/HALOGEN 4.00 -0.20 -2.80 4.89 DAY 0 - DAY 28 SALINE AL* 0.29 Aa* 0.33 <000 AE* 1.07 ARGON -0.16 0.32 -4.03 4.05 XENON 1.89 0.90 -3.42 4.01 T/HALOGEN 3.50 -0.07 -2.91 4.55 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B15 COLOUR PROGRESSION L* 6.00 5.00 4.00 3.00 2.00 1.00 0.00 1.00 -2.00 □Saline •0.20 -0.74 □Argon 4.32 0.46 -0.16 □Xenon 3.29 □T/Hal 5-12 Day 0-1 121 1.44 1.89 4.00 * 3.50 Day 0-14 Day 0-28 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B16 COLOUR PROGRESSION a* 0.8 0.6 0.4 -02 -0.4 0.07 0.33 □Argon 025 0.02 0.32 □Xenon ___________ -015___________ 038_______________ 0.90 □T/Hal_____________-0 3 3 ___________ -0.20_______________________-0.07 Day 0-1 Day 0-14 Day 0-28 122 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B17 COLOUR PROGRESSION b* 0.50 0.00 -0.50 - 1.00 -1.50 -2.00 -2.50 -3.00 -3.50 -4.00 1 2 3 □Same 0.00 0.04 -0.98 □Argon -4.28 -3.85 -4.03 □Xenon -3.56 -3.35 -3.42 □T/Hal ; -2.43 -2.80 -2.91 OayO-1 Day 0-1 4 DayO-28 123 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B18 COLOUR PROGRESSION E* 0 □Saline □Argon 1 j-------------- tn m V'-'taU 3 4 ^ v* -V^.t sn;?r lit asSirar Stt 1 0.21 e7o9 2 08 3.88 3 1.07 4~05 □Xenon □T/Hal 4.85 5.68 Day 0 -1 3.67 4.89 Day 0-14 4.01 4.55 DayO-28 124 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE B19 SIGNIFICANT DIFFERENCE: ONE TAIL VS. TWO TAIL DAY 0 - DAY 1 AL* Aa* Ab* AE* Argon - Saline 2t 2t 2t Argon - Xenon Argon - T/Hal 2t 2t Xenon - Saline 2t 2t 2t Xenon - T/Hal 2t T/Hal - Saline 2t 2t 2t SIGNIFICANT DIFFERENCE: ONE TAIL VS. TWO TAIL DAY 0-DAY14 AL* Aa* Ab* AE* Argon - Saline 2t 2t Argon - Xenon Argon - T/Hal 2t 2t Xenon - Saline 2t 1t Xenon -T/Hal 1t 1t T/Hal - Saline 2t 2t 2t SIGNIFICANT DIFFERENCE: ONE TAIL VS. TWO TAIL DAY 0 - DAY 28 AL* Aa* Ab* AE* Argon - Saline 2t 2t Argon - Xenon 1t 1t Argon - T/Hal 2t 2t Xenon - Saline 2t 2t Xenon - T/Hal 2t T/Hal-Saline 2t 2t 2t Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX “C” STATISTICAL CALCULATIONS t-Test: Paired Two Sample for Means SaHM L RmcMm i 0;t Variable 1 Variable 2 Mean 33.07 32.87 Variance 35.11 26.84 Observations 30 30 Pearson Correlation 0.68 Hypothesized Mean Difference 0 df 29 t Stat 0.29 P(T<=t) one-tail 0.40 t Critical one-tail 1 70 P(T<=t) two-tail 0.80 t Critical two-tail 205 |t-Test: Paired Two Sample for Means Salirine L Reading 1:14__________ Me 32.87^ 32.33 26.84 23.91 3q 30 0.79 29 0.81| 0.21 1.70 0.42] 2.05( .Jiean j Variance i Observations J Pearson Correlation j (Hypothesized Mean Difference | jdf i jt Stat | P(T<=t) one-tail t Critical one-tail j P(T<=t) two-tail j t Critical two-tail > 2.09 j jt-Test: Paired Two Sample for Means mHii» LR—dlnQ 14:28 Variable 1 Variable 2 Mean 32.33 33.36 Variance 23.91 40.97 Observations 30 30 Pearson Correlation 0.74 Hypothesized Mean Difference 0 29 t Stat -1.31 P(T<=t) one-tail 0.10 t Critical one-tail 1.70 P(T<=t) two-tail 0.20 | Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Saline a Reading 0:1 Variable 1 Variable 2 Mean -1.06 -0.99 Variance 0.78 0.93 Observations 30 30 Pearson Correlation 0.15 Hypothesized Mean Difference o I* 29 it Stat -0.29 P(T<=t) one-tail 0.39 t Critical one-tail 1.70 P(T<=t) two-tail 0.77 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Batina a Reacflna 1:14 Variable 1 Variable 2 Mean -0.99 -0.77 Variance 0.93 1.83 Observations 30 30 Pearson Correlation 0.26 Hypothesized Mean Difference 0 df 29 t Stat -0.84 P(T<=t) one-tail 0.20 t Critical one-tail 1.70 P(T<=t) two-tail 0.41 t Critical two-tail 2.05 ■ [t-Test: Paired Two Sample for Means Saline a Reading 14:28 ! Variable 1 Variable 2 Mean -0.77i -0.73) Variance 1.83 0.67 Observations 30 30 Pearson Correlation -0.04 Hypothesized Mean Difference o df 29 t Stat -0.15 P(T<=t) one-tail 0.44 t Critical one-tail 1.70 P(T<=t) two-tail 0.88 t Critical two-tail 2.0452308 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. [t-Test: Paired Two Sample for Means «ne b ReadbigOtf Variable 1 Variable 2 Variance Observations Pearson Correlation Hypothesized Mean Difference df tStat |P(T<=t) one-tail jt Critical one-tail :P(T<=t) two-tail t Critical two-tail 2.38 4.39 30 t-Test: Paired Two Sample for Means BaRm b Raadbia 1:14 Variable 1 Variable 2 Mean 2.38 2.42 Variance 4.39 5.46 Observations 30 30 Pearson Correlation 0.49 Hypothesized Mean Difference 0 df 29 tStat -0.11 P(T<=t) one-tail 0.48 t Critical one-tail 1.70 P(T<=t) two-tail 0.91 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Saline b Reading 14:28 I l Variable 1 Variable 2 Mean 2.42 1.40 [Variance 5.46 3.61 “Observations 30 30 Pearson Correlation 0.48 Hypothesized Mean Difference 0 f 29 t Stat 2.55 jP(T<=t) one-tail 0.01 t Critical one-tail 1.70 jP(T<=t) two-tail 0.02 1 Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Argon L RaacNng 0:1 Variable 1 Variable 2 Mean 34.16 38.48 Variance 37.39 40.14 Observations 30 30 Pearson Correlation 0.42 Hypothesized Mean Difference d df 29 t Stat -3.51 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means ! Variable 1 Variable 2 Mean 38.48 34.64 Variance 40.14 29.30 Observations 30 30 Pearson Correlation 0.31 Hypothesized Mean Difference 0 df 29 t Stat 3.02 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means i L Reading 14:28_________ Variable 1 Variable 2 lean Variance Observations Pearson Correlation Hypothesized Mean Difference ft Stat !P(T<=t) one-tail It Critical one-tail |p(T<=t) two-tail Critical two-tail i 34.64 34.00 29.30 35.20 30 30 0.71 0 29 0.82 0.21 1.70 0.42 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. jt-Test: Paired Two Sample for Means Argon a Roaring 0:1___________ I—- ------------------------------------------- I I Variable 1 I Variable 2j Mean -0.92j -0.67 Variance 0.83 0.81 Observations ! 3d 30j jPearson Correlation j -0.07] Hypothesized Mean Difference df ! 2d t Stat -1.03 P(T<=t) one-tail 0.16| t Critical one-tail i.7a P(T<=t) two-tail 0.3lj t Critical two-tail 2.05I t-Test: Paired Two Sample for Means iaRM dna1:14 _______ Variable 1 Variable 2 Mean j -0.67 Variance i 0.81 Observations ! 30 Pearson Correlation i o.id Hypothesized Mean Difference ! d Idf ! 29 t Stat j i.id P(T<=t) one-tail i 0.13 t Critical one-tail j i.7d P(T<=t) two-tail ! 0.26 t Critical two-tail j 2. OS -0.90 0.61 30 I t-Test: Paired Two Sample for Means Argon a Rearing 14:28____________________ j ■ ! Variable 1 1 Variable 2 j Mean -0.90j -0.6d Variance 0.61 0.46j Observations I 30( 30j Pearson Correlation 0.28) i 'Hypothesized Mean Difference I d idf 29( jt Stat -1.92) i P(T<=t) one-tail ; i jt Critical one-tail 170 P(T<=t) two-tail j o.od j i 1 Critical two-tail I 2.0S Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. [t-Test: Paired Two Sample for Means iAiqon b Reeding 0:1 _________ Variable 1 Variable 2 Mean [Variance Observations 'Pearson Correlation Hypothesized Mean Difference j* t Stat |P(T<=t) one-tail It Critical one-tail |P(T<=t) two-tail t Critical two-tail 2.05! -3.19 2.89 30 t-Test: Paired Two Sample for Means b RewBna 1:14 Variable 1 Variable 2 Mean -3.19 -2.76 Variance 2.89 3.58 Observations 30 30) Pearson Correlation 0-5S Hypothesized Mean Difference Q 2S t Stat -1.43 P(T<=t) one-tail 0.08 t Critical one-tail 1.70 P(T<=t) two-tail 0.16 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means lArgon b Reading 14:28 I i Variable 1 1Variable 2 jMean ! -2.76( -2.941 Variance | 3.58) 3.45j Observations ; 3P 30 iPearson Correlation 0.83j | 'Hypothesized Mean Difference t Stat 29 i 0.93) P(T<=t) one-tail 0.10 ! It Critical one-tail 1701 |P(T<=t) two-tail 1 0.36) i t Critical two-tail ! 2.09 i Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. It-Test: Paired Two Sample for Means mnon L RmkHihi Otl Variable 1 Variable 2 jMean 38.51 41.80 Variance 62.22 91.83 observations 30 30 Pearson Correlation 0.77 Hypothesized Mean Difference d F 29 t Stat -2.96 |P(T<=t) one-tail 0.00 jt Critical one-tail 1.70 P(T<=t) two-tail 0.01 jt Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xanon L RmkHik i 1:14 Variable 1 Variable 2 Mean 41.80 39.95 Variance 91.83 67.10 Observations 30 30 Pearson Correlation 0.80 Hypothesized Mean Difference d df 29 t Stat 1.76 p(T<=t) one-tail 0.04 It Critical one-tail 1.70 P(T<=t) two-tail 0.09 |t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means jXenon L R—tMng 14:28__________ jMean Variance Observations Pearson Correlation Hypothesized Mean Difference jt Stat P(T<=t) one-tail t Critical one-tail P(T<=t) two-tail t Critical two-tail Variable 1 Variable 2 39.95 40.40 67.10 74.58 30 3d 0.78 0 29 -0.44 0.33 1.70 0.66 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Xenon a ReacNnctOrl Variable 1 Variable 2 Mean -1.54 -1.69 Variance 1.89 1.47 Observations 30 30l Pearson Correlation 0.50 Hypothesized Mean Difference 0 df 29 j t Stat 0.61 P(T<=t) one-tail 0.27 t Critical one-tail 1.70 P(T<=t) two-tail 0.55 t Critical two-tail 2.05 *-Test: Paired Two Sample for Means Xanon a flaadtag 1:14 Variable 1 Variable 2 Mean -1.69 -1.16 Variance 1-4' 0.55 Observations 30 30 Pearson Correlation 0.19 Hypothesized Mean Difference o df 29 t Stat -2.21 P(T<=t) one-tail 0.02 t Critical one-tail 1.7C P(T<=t) two-tail 0.04 t Critical two-tail 2 Op It-Test: Paired Two Sample for Means iX en o n aR — d&K» 1 4 :2 8 ___________ Variable 1 Variable 2 Mean /ariance Observations jPearson Correlation Hypothesized Mean Difference F t Stat |P(T<=t) one-tail It Critical one-tail !p(T<=t) two-tail It Critical two-tail -1.19 -0.64 0.59 0.65 3q 30 0.20| 0| 29 -2.89I o.oq i.7q 0.01 2.05( Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Xanottb RMdfcMtOrt Variable 1 Variable 2 Mean 1.25 -2.31 Variance 6.36 3.79 Observations 30 30 Pearson Correlation 0.68 Hypothesized Mean Difference 0 df 29 it Stat 10.46 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xanon b Reading 1:14 Variable 1 Variable 2 Mean -2.31 -2.10 Variance 3.79 4.94 Observations 30 30 Pearson Correlation 0.70 Hypothesized Mean Difference 0 df 29 t Stat -0.72 P(T<=t) one-tail 0.24 t Critical one-tail 1.70 P(T<=t) two-tail 0.48 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xenon b Reading 14:2t Variable 1 Variable 2 Mean -2.10 -2.17 Variance 4.94 3.98 Observations 30 30 Pearson Correlation 0.79 Hypothesized Mean Difference 0 29 t Stat 0.30 P(T<=t) one-tail 0.38 t Critical one-tail 1.70 P(T<=t) two-tail 0.77 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means TtMbom LFtMkRria 0:1 Variable 1 I Variable 2 Mean 33.19 38.31 Variance 42.28 33.78I Observations 39 30 Pearson Correlation 0.61 Hypothesized Mean Difference oj df 29 t Stat -5.14 P(T<=t) one-tail o.oq t Critical one-tail 1.7a P(T<=t) two-tail o.oq jt Critical two-tail 2.05I ____ t-Test: Paired Two Sample for Means THaloam L Reading 1:14 Variable 1 Variable 2 Mean 38.31 37.19 Variance 33.78 34.24 Observations 30 30 Pearson Correlation 0.70 Hypothesized Mean Difference o| df 29 t Stat 1.37 P(T<=t) one-tail 0.09 t Critical one-tail 1.70 P(T<=t) two-tail 0.18 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means THatogen L Readbio 14:28 ! Variable 1 Variable 2 Mean 37.19 36.69 Variance 34.24 26.81 Observations 30 30 Pearson Correlation 0.81 Hypothesized Mean Difference 0 df 29 t Stat 0.79 jP(T<=t) one-tail 0.22 t Critical one-tail 1.70 jp(T <=t) two-tail 0.44 It Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means THalogeti a R—ding 0:1 Variable 1 Variable 2 Mean -0.93 -1.26 Variance 0.84 0.88 Observations 30 30 Pearson Correlation 0.26 Hypothesized Mean Difference 0 df 29 t Stat 1.62 P(T<=t) one-tail 0.06 t Critical one-tail 1.70 P(T<=t) two-tail 0.12 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means THakMwn a Readtoa .1:14 Variable 1 Variable 2 Mean -1.26 -1.13 Variance 0.88 0.82 Observations 30 30 Pearson Correlation 0.34 Hypothesized Mean Difference 0 df 29 t Stat -0.67 P(T<=t) one-tail 0.25 t Critical one-tail 1.70 P(T<=t) two-tail 0.51 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means THalogwi a Reading 14:28 Variable 1 Variable 2 Mean -1.13 -1.00 Variance 0.82 0.73 Observations 30 30 Pearson Correlation 0.39 Hypothesized Mean Difference 0 df 29 tStat -0.74I P(T<=t) one-tail 0.23 f Critical one-tail 1.70 P(T<=t) two-tail 0.47 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means THalooen bfteadfnoOrf Variable 1 Variable 2 Mean 1.56 -0.87 Variance 7.08 7.19 Observations 30 30 Pearson Correlation 0.88 Hypothesized Mean Difference d df 29 ^ Stat 10.29 P(T<=t) one-tail 0.00 jt Critical one-tail 1 70 jP(T<=t) two-tail 0.00 jt Critical two-tail 2.05 t-Test: Paired Two Sample for Means THUooan b fl—dina 1:14 Variable 1 Variable 2 Mean -0.87 -1.24 Variance 7.19 5.40 Observations 30 30 Pearson Correlation 0.88 Hypothesized Mean Difference d df 29 t Stat 1.65 P(T<=t) one-tail o.oe t Critical one-tail 1.70 jp(T <=t) two-tail 0.11 |t Critical two-tail 2.05 t-Test: Paired Two Sample for Means THaloQM b RMcRna 14:28 Variable 1 Variable 2 Mean -1.24 -1.35 Variance 5.4d 6.01 Observations 30 30 Pearson Correlation 0.94 Hypothesized Mean Difference d df 29 t Stat 0.70 P(T<=t) one-tail 0.24 t Critical one-tail 1.70 P(T<=t) two-tail 0.49 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SiHni to Argon Day 0 -Day 1 AL* Variable 1 Variable 2 Mean -0.21 4.32 Variance 19.90 45.29 Observations 3q 30 Pearson Correlation -0.20 Hypothesized Mean Difference 0 df 29 t Stat -2.82 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaHM to Araon OnrO • Dm 14 AL* Variable 1 Variable 2 Mean -0.74 0.48 Variance 18.64 18.83 Observations 30 30 Pearson Correlation 0.11 Hypothesized Mean Difference Q df 2^ t Stat -1.16 P(T<=t) one-tail 0.13 t Critical one-tail 1.70 P(T<=t) two-tail 0.26 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means balina to Argon Day 0 - Day 28 AL* | Variable 1 Variable 2 Mean 0.29 -0.17 Variance 24.15 23.85 observations 30 30 jPearson Correlation -0.03 Hypothesized Mean Difference C r 29 It Stat 0.35 |P(T<=t) one-tail 0.36 It Critical one-tail 1.70 P(T<=t) two-tail 0.73 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Saline to Xanon Day 0 - Day 1 AL* Variable 1 Variable 2 Mean -0.21 3.29 Variance 19.90 37.03 Observations 30 30 Pearson Correlation -0.03 Hypothesized Mean Difference r 0 29 t Stat -2.50 P(T<=t) one-tail 0.01 jt Critical one-tail 1.70 |P(T<=t) two-tail 0.02 |t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Saline to XanonPay 0 - Day 14 Ab* Variable 1 Variable 2 Mean 0.04 -3.34 Variance 5.81 4.39 Observations 30 30 Pearson Correlation 0.09 Hypothesized Mean Difference 0 df 29 t Stat 6.07 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 |t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaHiw to Xanon Day0 -Day »A L * Variable 1 Variable 2 Mean 0.29 1.89 Variance 24.15 48.49 Observations 30 30 Pearson Correlation 0.04 Hypothesized Mean Difference 0 df 29 t Stat -1.05 P(T<=t) one-tail 0.15 jt Critical one-tail 1.70 P(T<=t) two-tail 0.30 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Sadi* to T/HHooen Day 0 -Day 1 AL* Variable 1 Variable 2 Mean -0.21 5.12 Variance 19.90 29.84 Observations 30 30 Pearson Correlation 0.18 Hypothesized Mean Difference 0 df 29 t Stat -4.55 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Sauna to T/Hakwan Day 0-Day 14 AL* Variable 1 Variable 2 Mean -0.74 4.oq Variance 18.64 35.71 Observations 30 30 Pearson Correlation 0.10 Hypothesized Mean Difference 0 df 29 t Stat -3.70 P(T<=t) one-tail o.oo t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Sauna to TftMooan Day O-Dav 28 AL* j Variable 1 1Variable 2 Mean I 0.20 3.50 Variance 24.15) 35.97 Observations 30| 30 Pearson Correlation 0.15 Hypothesized Mean Difference df 29 Jt Stat ! -2.47) P(T<=t) one-tail ! 0.01 jt Critical one-tail 1.7a |P(T<=t) two-tail ! 0.02 f Critical two-tail ! 2.0fi| Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Argon toXenonOayO-Day 1 AL* Variable 1 Variable 2 Mean 4.32 3.29 Variance 45.29 37.03 Observations 30 30 Pearson Correlation 0.12 Hypothesized Mean Difference 1* d 29 tStat 0.60 P(T<=t) one-tail 0.26 t Critical one-tail 1.70 P(T<=t) two-tail 0.51 t Critical two-tail 2.05 l-Test: Paired Two Sample for Means Argon to Xenon Day 0 -Day 14 AL* * Variable 1 Variable 2 Mean 0.48 1.44 Variance 18.83 45.16 Observations 30 30 Pearson Correlation 0.08 Hypothesized Mean Difference 0 df 29 tStat -0.68 P(T<=t) one-tail 0.25 t Critical one-tail 1.70 P(T<=t) two-tail 0.50 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Argon to Xenon Day 0 - Day 28 AL* Variable 1 Variable 2 Mean -0.17 1.89 Variance 23.85 48.49 Observations 30 30 Pearson Correlation 0.45 Hypothesized Mean Difference d df 29 tStat -1.74 P(T<=t) one-tail 0.05 t Critical one-tail 1.7d P(T<=t) two-tail 0.09 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means teqon to T/Hak>Qon Day 0 » Dw 1 AL* Variable 1 Variable 2 Mean 4.32 5.12 Variance 45.29 29.84 Observations 30 30 Pearson Correlation -0.22 Hypothesized Mean Difference 0 df 29 tStat -0.46 P(T<=t) one-tail 0.32 t Critical one-tail 1.70 P(T<=t) two-tail 0.65 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means tanon to TAMoomi Day 0>Day 14 AL* Variable 1 Variable 2 Mean 0.48 4.00 Variance 18.83 35.71 Observations 30 30 Pearson Correlation -0.34I Hypothesized Mean Difference 0 df 29 tStat -2.27 P(T<=t) one-tail 0.02 t Critical one-tail 1.70 P(T<=t) two-tail 0.03 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means teaon to T/Holoaon Dov 0-Day 28 At* Variable 1 Variable 2 Mean -0.17 3.50 Variance 23.85 35.97 Observations 30 30 Pearson Correlation -0.23 Hypothesized Mean Difference 0 df tStat 29 -2.35 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail 0.03 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Xenonto T/Halooen Day 0 -Day t AL* Variable 1 Variable 2 Mean 3.29 5.12 Variance 37.03 29.84 Observations 30 30 Pearson Correlation -0.19 Hypothesized Mean Difference 0 df 29 tStat -1.141 P(T<=t) one-tail 0.19 t Critical one-tail 1.70 P(T<=t) two-tail 0.26 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xanon to TAMooan Day0-Oav 14 AL* Variable 1 Variable 2 Mean 1.44 4.00 y/ariance 45.16 35.71 Observations 30 30 Pearson Correlation 0.14 Hypothesized Mean Difference 0 df 29 tStat -1.60 P(T<=t) one-tail 0.09 t Critical one-tail 1.70 P(T<=t) two-tail 0.10 t Critical two-tail 2.09 {t-Test: Paired Two Sample for Means IXenon to T/Halogen Day O-Oay 28 AL* Variable 1 Variable 2 {Mean 1.89 3.50 {Variance 48.49 35.97 {Observations 30 30| Pearson Correlation -0.16 Hypothesized Mean Difference 29 {tStat -0.90 P(T<=t) one-tail 0.19 ft Critical one-tail 1.70 P(T<=t) two-tail 0.38 jt Critical two-tail 2.09 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means M in i to Awow Pi» 0 • Pirl Variable 1 Variable 2 jMean [Variance Observations IPearson Correlation Hypothesized Mean Difference gtStat P(T<=t) one-tail t Critical one-tail P(T<=t) two-tail t Critical two-tail 0.06 0.25 1.44 1.75 30 30 0.25 0 29 -0.65 0.26 1.70 0.52 2.05 t-Test: Paired Two Sample for Means Saline to Anion Day 0 - Day 14 A** Variable 1 Variable 2 Mean 0.29 0.01 Variance 1.76 1.11 Observations 30 30 Pearson Correlation 0.09 Hypothesized Mean Difference 0 df 29 tStat 0.93 P(T<=t) one-tail 0.18 t Critical one-tail 1.70 P(T<=t) two-tail 0.36 t Critical two-tail 2.05 . t-Test: Paired Two Sample for Means Saline to Araon Day 0 • Day 28 Aa* Variable 1 Variable 2 Mean 0.33 0.32) Variance 1.43 1.09 Observations 30 30 Pearson Correlation -0.03 Hypothesized Mean Difference 0 29 tStat 0.04 P(T<=t) one-tail 0.49 t Critical one-tail 1.70 P(T<=t) two-tail 0.97 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. [t-Test: Paired Two Sample for Means BaHiIn* to X w o n D irJ -D « y 1 An* Mean Variance observations Pearson Correlation Hypothesized Mean Difference |t Stat P(T<=t) one-tail |t Critical one-tail IP(T<=t) two-tail It Critical two-tail Variable 1 Variable 2 0.06 -0.14 1.44 1.68 30 30 -0.34 0 29 0.56 0.29 1.70 0.58 2.05 t-Test: Paired Two Sample for Means BaRmto Xenon Dav 0 - Day 14 Aa* Variable 1 Variable 2 Mean 0.29 0.39 Variance 1.76 2.13 Observations 30 30) Pearson Correlation -0.18 Hypothesized Mean Difference 0 df 29 t Stat -0.25 P(T<=t) one-tail 0.40 t Critical one-tail 1.70 P(T<=t) two-tail 0.80 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Selin* to Xenon Day 0 - Day 28 A** i Variable 1 Variable 2 Mean 0.33 0.90 Variance 1.43 2.32 Observations 30 30 Pearson Correlation -0.11 Hypothesized Mean Difference 0 Idf 29 t Stat -1.54 P(T<=t) one-tail 0.07 t Critical one-tail 1.70 P(T<=t) two-tail 0.13 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SaHneto T/llafooen Day O -D ayltU * Variable 1 Variable 2 Mean 0.06 -0.33 Variance 1.44 1.27 Observations 30 30 Pearson Correlation 0.05 Hypothesized Mean Difference 0 df 29 t Stat 1.35 P(T<=t) one-tail 0.09 t Critical one-tail 1.70 P(T<=t) two-tail 0.19 t Critical two-tail 2.05 [-Test: Paired Two Sample for Means to T/Hakwn DavO-Oay 14 Aa* Variable 1 Variable 2 Mean 0.29 -0.20 Variance 1.76 0.87 Observations 30 30 Pearson Correlation -0.42 Hypothesized Mean Difference 0 df 29 t Stat 1.40 P(T<=t) one-tail 0.09 t Critical one-tail 1.70 P(T<=t) two-tail 0.17 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Saline to T/Hatooan Day O-Oav 28 Aa* ■ 1 Variable 1 Variable 2 Mean 0.33 -0.07 Variance 1.43 1.59 Observations 30 30 Pearson Correlation -0.06 Hypothesized Mean Difference 1* 0 29 t Stat 1 23 P(T<=t) one-tail 0.11 t Critical one-tail 1 70 P(T<=t) two-tail 0.23 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Argon to Xenon Pay 8 ~ P art Aaf Variable 1 Variable 2 Mean 0.25 -0.14 Variance 1.75 1.68 Observations 30 30 Pearson Correlation 0.06 Hypothesized Mean Difference 0 rt Stat 29 1.20 P(T<=t) one-tail 0.12 t Critical one-tail 1.70 P(T<=t) two-tail 0.24 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Argon to Xenon Pay 8 -Pay 14 Aa* Variable 1 Variable 2 Mean 0.01 0.39 Variance 1.11 2.13 Observations 30 30 Pearson Correlation 0.06 Hypothesized Mean Difference 0 df 29 t Stat -1.17 P(T <=t) one-tail 0.13 t Critical one-tail 1.70 P(T<=t) two-tail 0.25 t Critical two-tail 2.05 |t-Test: Paired Two Sample for Means iArqow to Xenon Pay 0 -Pay 38 Ai* Variable 1 Variable 2 Mean 0.32 0.90 Variance 1.09 2.32 Observations 30 30 Pearson Correlation 0.17 Hypothesized Mean Difference 0 df 29 t Stat -1.89 P(T<=t) one-tail 0.03 t Critical one-tail 1.70 P(T<=t) two-tail 0.07 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. :-Test: Paired Two Sample for Means Iw ob to T/Halooen Dey 0 - Pay 1 A **_________________ Variable 1 Variable 2 Mean 0.25 -0.33 Variance 1.75 1.27 Observations 30 30 Pearson Correlation 0.40 Hypothesized Mean Difference 0 df 29 tStat 2.36 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail 0.03 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Anon to TffWoom Day 0>0iy 14 A«T Variable 1 Variable 2 Mean 0.01 -0.20 Variance 1.11 0.871 Observations 30 30 Pearson Correlation 0.02 Hypothesized Mean Difference 0 29 t Stat 0.84 P(T<=t) one-tail 0.20 t Critical one-tail 1.70 P(T<=t) two-tail 0.41 t Critical two-tail 2.05 [t-Test: Paired Two Sample for Means lArnon toT/HalogeoPay O-Pw 2» A** Variable 1 Variable 2 Mean 0.32 -0.07 Variance 1.09 1.59 Observations 30 30 Pearson Correlation 0.25 Hypothesized Mean Difference 0 df 29 t Stat 1.51 P(T<=t) one-tail 0.07 t Critical one-tail 1.70 P(T<=t) two-tail 0.14 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Xenon to T/llatooen Dw 0 - Day 1 Aa* Variable 1 Variable 2 Mean -0.14 -0.33 Variance 1.68 1.27 Observations 30 30 Pearson Correlation -0.12 Hypothesized Mean Difference 0 df 29 t Stat 0.56 P(T<=t) one-tail 0.29 t Critical one-tail 1.70 P(T<=t) two-tail 0.58 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Kinon to T/Hatooen Dev 0-Day 14 Aa* Variable 1 Variable 2 Mean 0.39 -0.20 Variance 2.13 0.87 Observations 30 30 Pearson Correlation 0.09 Hypothesized Mean Difference 0 df 29 t Stat 1.94 P(T<=t) one-tail 0.03 I Critical one-tail 1.70 P(T<=t) two-tail 0.06 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means Xenon to T/Helooen Pay Q-Oev28Ae* Variable 1 Variable 2 jMean 0.90 -0.07 Variance 2.32 1.59 Observations 30 30 |Pearson Correlation 0.06 (Hypothesized Mean Difference 0 kx 29 tStat 2.78 |P(T<=t) one-tail 0.00 t Critical one-tail 1.70 jp(T<=t) two-tail 0.01 It Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. jt-Test: Paired Two Sample for Means Mln>teMwitDirO‘PiiftAy______________________ I Variable 1 Variable 2 Mean -0.01 -4.28 Variance 1.52 3.52 Observations 30 30 Pearson Correlation 0.04 Hypothesized Mean Difference 0 df 29 t Stat 10.63 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means BaNnatoAraonDayO«Day14Ab* Variable 1 Variable 2 Mean 0.04 -3.85 Variance 5.81 1.52 Observations 30 30 Pearson Correlation -0.03 Hypothesized Mean Difference 0 df 29 t Stat 7.77 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(Ts=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Salim to Aroon Day 0 - Day 28 Ab* Variable 1 Variable 2 Mean -0.98 -4.03 Variance 1.19 1.62 Observations 30 30 Pearson Correlation -0.13 Hypothesized Mean Difference 0 jdf 29 t Stat 9.42 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. [t-Test: Paired Two Sample for Means bannsto Xenon Day 0 * Day TAb* Variable 1 Variable 2 [Mean -0.01 -3.56 variance 1.52 3.48 Observations 30 30 Pearson Correlation -0.16 Hypothesized Mean Difference 0 29 jt Stat 8.13 P(T<=t) one-tail 0.00 |t Critical one-tail 1.70 |P(T<=t) two-tail 0.00 |t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaHna to Xenon Day 0 • Day 14 Ab* Variable 1 Variable 2 Mean 0.04 -3.34 Variance 5.81 4.39 Observations 30 30 Pearson Correlation 0.09 Hypothesized Mean Difference 0 df 29 t Stat 6.07 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaHne to Xanon Day 0 - Day 24 Ab* Variable 1 Variable 2 Mean -0.98 -3.42 Variance 1.19 2.72 Observations 30 30 Pearson Correlation 0.14 Hypothesized Mean Difference 0 df 29 tStat 7.27 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SaHiw to T/Hatogan Day O - Day 1 Ab* Variable 1 Variable 2 Mean -0.01 -2.43 Variance 1.52 1.67 Observations 30 30 Pearson Correlation 0.15 Hypothesized Mean Difference 0 df 29 't Stat 8.04 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means BaNna to T/Haloaan Oav (Mtav 14 Ab* Variable 1 Variable 2 Mean 0.04 -2.81 Variance 5.81 2.27 Observations 30 30 Pearson Correlation 0.19 Hypothesized Mean Difference 0 df 29 t Stat 6.02 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Variable 1 Variable 2 Mean -0.98 -2.92 Variance 1.19 2.62 Observations 30 30 Pearson Correlation 0.01 Hypothesized Mean Difference 0 df 29 tStat 5.45 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. (t-Test: Paired Two Sample for Means Union to XanoitDiy 0 • Ooy 1 Ab* Variable 1 Variable 2 (Mean -4.28 -3.56 Variance 3.52 3.48 observations 30 30| Pearson Correlation -0.18 Hypothesized Mean Difference 0 29 tStat -1.38 jP(T<=t) one-tail 0.09 It Critical one-tail 1.70 jP(T<=t) two-tail 0.18 |t Critical two-tail 2.05 (t-Test: Paired Two Sample for Means Variable 1 Variable 2 Mean -3.85 -3.34 Variance 1.52 4.39 Observations 30 30 Pearson Correlation -0.30 Hypothesized Mean Difference 0 df 29 t Stat -1.02 P(T<=t) one-tail 0.16 t Critical one-tail 1.70 P(T<=t) two-tail 0.32 I Critical two-tail 2.05 t-Test: Paired Two Sample for Means Argon to Xonon Day 0 - Day 28 Ab* Variable 1 Variable 2 Mean -4.03 -3.42 Variance 1.62 2.72j Observations 30 30 Pearson Correlation -0.11 Hypothesized Mean Difference 0 29 t Stat -1.54 P(T<=t) one-tail 0.07 t Critical one-tail 1.70 P(T<=t) two-tail 0.14 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Amon toT/Naioawi DoyO-Day 1 Ab* Variable 1 Variable 2 Mean -4.28 -2.43 Variance 3.52 1.67 Observations 30 30 Pearson Correlation 0.01 Hypothesized Mean Difference 0 df 29 It Stat -4.48 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Anion to TAMoaon Day O-Onr 14 Ab* Variable 1 Variable 2 Mean -3.85 -2.81 Variance 1.52 2.27 Observations 30 30 Pearson Correlation -0.43 Hypothesized Mean Difference 0 df 29 t Stat -2.46 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail 0.02 t Critical two-tail 2.05 [t-Test: Paired Two Sample for Means Argon to T/Halogen Day O-Oay 28 All*__________________ I Variable 1 Variable 2 Mean -4.03 -2.92 Variance 1.62 2.62 Observations 30 30 Pearson Correlation -0.27 Hypothesized Mean Difference 0 df 29 t Stat -2.65 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail t Critical two-tail 0.01 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Xenon to T/Halogen Day 0-Day T Ab* Variable 1 Variable 2 Mean -3.56 -2.43 Variance 3.48 1.67 Observations 30 30 Pearson Correlation -0.11 Hypothesized Mean Difference 0 df 29 t Stat -2.60 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xenon to T/Halogen Day 0*Day 14 Ab* Variable 1 Variable 2 Mean -3.34 -2.81 Variance 4.39 2.27 Observations 30 30 Pearson Correlation 0.16 Hypothesized Mean Difference 0 df 29 t Stat -1.24 P(T<=t) one-tail 0.11 t Critical one-tail 1.70 P(T<=t) two-tail 0.23 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Xenon lo T/Halogen Day 0-Oav 284b* Variable 1 Variable 2 Mean -3.42 -2.92 Variance 2.72 2.62 Observations 30 30 Pearson Correlation -0.04 Hypothesized Mean Difference 0 Idf 29 tStat -1.17 P(T<=t) one-tail 0.13 t Critical one-tail 1.70 P(T<=t) two-tail 0.25 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SaNna to Aigon DarO •D a ri A P 1 Variable 1 Variable 2 Mean 3.97 8.38 Variance 6.60 16.31 Observations 30 30 Pearson Correlation 0.28 Hypothesized Mean Difference 0 df 29 it Stat -5.84 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.00 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaNna to Anon Day 0 > 08914 AP Variable 1 Variable 2 Mean 4.36 5.65 Variance 7.23 4.07 Observations 30 30| Pearson Correlation 0.10 Hypothesized Mean Difference 0 29 p Stat -2.21 P(T<=t) one-tail 0.02 1 Critical one-tail 1.70 P(T<=t) two-tail 0.04 |t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means BaHnatoAfaoi>OayO«Oay2>AP Variable 1 Variable 2 Mean 4.31 6.11 {Variance 8.70 4.96 {Observations 30 30 Pearson Correlation 0.14 {Hypothesized Mean Difference 0 29 jt Stat -2.86 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SaNn* to Xenon Day0 - Day 1 AP Variable 1 Variable 2 Mean 3.97 6.55 Variance 6.60 22.16 Observations 30 30 Pearson Correlation -0.01 Hypothesized Mean Difference 0 df 29 t Stat -2.62 P(T<=t) one-tail 0.01 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means SaNm to Xonon Day 0 • Ow 14 AP Variable 1 Variable 2 Mean 4.36 6.14 Variance 7.23 26.50 Observations 30 30 Pearson Correlation 0.06 Hypothesized Mean Difference 0 df 29 t Stat -1.73 P(T<=t) one-tail 0.05 t Critical one-tail 1.70 P(T<=t) two-tail 0.09 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means HmtoXWionP«yO-P«y2tAP Variable 1 Variable 2 Mean 4.31 6.45 Variance 8.70 27.13 Observations 30 30 Pearson Correlation 0.13 Hypothesized Mean Difference 0 df 29 t Stat -2.08 P(T<=t) one-tail 0.02 t Critical one-tail 1.70 P(T<=t) two-taii 0.05 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means SaNm to T/IWomn Day0 - Day 1A F Variable 1 Variable 2 Mean 3.97 6.74 Variance 6.60 19.12 Observations 30 30 Pearson Correlation -0.04 Hypothesized Mean Difference df 0 29 t Stat -2.94 P(T<=t) one-tail 0.00 t Critical one-tail 1.70 P(T<=t) two-tail 0.01 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means M m to TAWoom Dw O-Ow 14 AP Variable 1 Variable 2 Mean 4.36 6.58 Variance 7.23 18.72 Observations 30 30 Pearson Correlation -0.20 Hypothesized Mean Difference 0 df 29 t Stat -2.21 P(T<=t) one-tail 0.02 t Critical one-tail 1.70 P(T<=t) two-tail 0.04 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Ira to T/Hatogwi Day O-Pwr 28 AE* I j Variable 1 Variable 2 Mean 4.31 6.73 Variance 8.70 14.87 {Observations 30 30 Pearson Correlation 0.13 Hypothesized Mean Difference r 0 29 jt Stat -2.91 P(T<=t) one-tail 0.00 |t Critical one-tail 1.70 jP(T<=t) two-tail 0.01 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Anion to XenonDeyO- DoyfAP I Variable 1 Variable 2 Mean 8.38 6.55 Variance 16.31 22.16 Observations 30 30 Pearson Correlation -0.12 Hypothesized Mean Difference 0 idf 29 tStat 1.52 P(T<=t) one-tail 0.07 t Critical one-tail 1.70 P(T<=t) two-tail 0.14 t Critical two-tail 2.05 t-Test: Paired Two Sample for Means Araon to Xenon DeyO-Day 14 AP Variable 1 Variable 2 Mean 5.65 6.14 Variance 4.07 26.50 Observations 30 30 Pearson Correlation 0.16 Hypothesized Mean Difference 0 df 29 t Stat -0.52 r(T<=t) one-tail 0.30 I Critical one-tail 1.70 P(T<=t) two-tail 0.61 |t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means lArgon to Xenon Day 0 -Day 2S AP ! Variable 1 Variable 2 jMean 6.11 6.45 Variance 4.96 27.13 observations 30 30 jPearson Correlation 0.21 jHypothesized Mean Difference rif 0 29 jt Stat -0.36 |P(T<=t) one-tail 0.36 it Critical one-tail 1.70 |P(T<=t) two-tail 0.72 |t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Araon to T/Halogen Day 0 -oayfAE* Variable 1 Variable 2 Mean 8.38 6.74 V/ariance 16.31 19.12 Observations 30 30 Pearson Correlation -0.43 Hypothesized Mean Difference 0 df 29 tStat 1.26 P(T<=t) one-tail t Critical one-tail 0.11 1.70 P(T<=t) two-tail 0.22 t Critical two-tail 2.05 jt-Test: Paired Two Sample for Means Argon to T/Halogen Day O-Oay 14 AP Variable 1 Variable 2 jan /ariance Jbservations searson Correlation hypothesized Mean Difference Stat J(T<=t) one-tail Critical one-tail *(T<=t) two-tail Critical two-tail 5.65 6.58 4.07 18.72 30 30I 0.57 0 29 -1.43 0.08 1.70 0.16 2.05 jt-Test: Paired Two Sample for Means Araon to T/Halogon Day O-Oay 28 AE* Variable 1 Variable 2 Mean 6.11 6.73 Variance 4.96 14.87 Observations 30 30 Pearson Correlation 0.28 Hypothesized Mean Difference 0 df 29 tStat -0.88 P(T<=t) one-tail 0.19 t Critical one-tail 1.70 P(T<=t) two-tail 0.39 t Critical two-tail 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t-Test: Paired Two Sample for Means Variable 1 Variable 2 Mean 6.55 6.74 Variance 22.16 19.12 Observations 30 30j Pearson Correlation 0.00 Hypothesized Mean Difference 0 I* 29 tStat -0.17 P(T<=t) one-tail 0.43 t Critical one-tail 1.70 P(T<=t) two-tail 0.87 t Critical two-tail 2.05 -Test: Paired Two Sample for Means i to T/Hilogen Day 0-D«y 14 AE* Variable 1 Variable 2 te an /ariance )bservations 3earson Correlation Hypothesized Mean Difference df t Stat |P(T<=t) one-tail It Critical one-tail jP(T<=t) two-tail i Critical two-tail 6.14 6.58 26.50 18.72 30 30 0.05 0 29 -0.37 0.36 1.70 0.72 2.05 jt-Test: Paired Two Sample for Means I [•non to T/Halogen Day O-Oay 28 AE*________________ 1 ! Variable 1 Variable 2 jMean Variance Observations |Pearson Correlation {Hypothesized Mean Difference k It Stat ;P(T<=t) one-tail it Critical one-tail |P(T<=t) two-tail I Critical two-tail 6.45 6.73 27.13 14.87 30 30t 0.21 0 29 -0.26 0.40 1.70 0.80 2.05 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. 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Asset Metadata
Creator
Wright, Robert Spence
(author)
Core Title
Vital tooth-whitening : An in-vitro study of three treatment modalities using argon laser, xenon pac-light and tungsten/halogen light systems
School
School of Dentistry
Degree
Master of Science
Degree Program
Craniofacial Biology
Degree Conferral Date
2000-08
Publication Date
08/08/2000
Defense Date
08/08/2000
Publisher
Los Angeles, California
(original),
University of Southern California
(original),
University of Southern California. Libraries
(digital)
Tag
OAI-PMH Harvest
Format
theses
(aat)
Language
English
Contributor
Digitized from microform by ProQuest
(provenance)
Advisor
Sinclair, Peter (
committee chair
), Mah, James (
committee member
), Sameshima Glen T. (
committee member
)
Permanent Link (DOI)
https://doi.org/10.25549/usctheses-oUC113992673
Unique identifier
UC113992673
Identifier
etd-WrightRobert-2000.pdf (filename)
Legacy Identifier
etd-WrightRobert-2000
Document Type
Thesis
Format
theses (aat)
Rights
Wright, Robert Spence
Internet Media Type
application/pdf
Type
texts
Source
20240610-usctheses-ostrow-proquest
(batch),
University of Southern California
(contributing entity),
University of Southern California Dissertations and Theses
(collection)
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The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the author, as the original true and official version of the work, but does not grant the reader permission to use the work if the desired use is covered by copyright. It is the author, as rights holder, who must provide use permission if such use is covered by copyright.
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