Afhandling - Copenhagen. / Summary in Danish.

Indiana University-Purdue University Indianapolis (IUPUI)

Afhandling - Copenhagen. / Summary in Danish.

by Yuen Pui-yee, Joyce. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 213-221). / Acknowledgments --- p.i / Abstract --- p.ii / List of Tables --- p.ix / List of Figures --- p.xi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Problems of Pollution From Textile Industries --- p.1 / Chapter 1.2 --- Current Treatment Methods of Wastewater from Textile Industries --- p.5 / Chapter 1.3 --- Adverse Effects of Dyes on the Environment --- p.11 / Chapter 1.4 --- Classification of Dyes --- p.16 / Chapter 1.5 --- Azo Dyes --- p.17 / Chapter 1.6 --- Metabolisms of Azo Dyes in Microbial and Animal Systems --- p.21 / Chapter 1.7 --- "Toxicity, Mutagenicity and Carcinogenicity of Azo Dyes" --- p.31 / Chapter 1.8 --- Removal of Azo Dyes --- p.35 / Chapter 1.8.1 --- Biological Methods --- p.35 / Chapter 1.8.2 --- Physico-chemical Methods --- p.49 / Chapter 1.9 --- Purposes of Study --- p.50 / Chapter 2. --- Objectives --- p.53 / Chapter 3. --- Materials and Methods --- p.54 / Chapter 3.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-Dimethyl-p-phenylene diamine-degrading Microbial Isolates" --- p.54 / Chapter 3.1.1 --- "Isolation of Methyl Red-degrading Microbial Isolates from Dye- containing Wastewater, Activated Sludge and Soil" --- p.54 / Chapter 3.1.2 --- Selection of Methyl Red-degrading Microbial Isolates --- p.56 / Chapter 3.1.3 --- "Enrichment of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria from Dye-containing wastewater, Activated Sludge and Soil" --- p.59 / Chapter 3.1.4 --- "Isolation of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.60 / Chapter 3.1.5 --- Selection of N，N-Dimethyl-p-phenylene diamine-degrading Bacteria --- p.60 / Chapter 3.1.6 --- "Identification of the Selected Methyl Red-degrading and N,N- Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.61 / Chapter 3.1.7 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.63 / Chapter 3.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.64 / Chapter 3.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.64 / Chapter 3.2.2 --- Change of UV-Vis Spectra of Methyl Red and N，N-Dimethyl-p- phenylene diamine at Different pH and Matrixes --- p.64 / Chapter 3.2.3 --- "UV-Vis Spectra and Standard Curves of Methyl Red, N，N- Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.66 / Chapter 3.2.4 --- "HPLC separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.67 / Chapter 3.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.68 / Chapter 3.3.1 --- "Monitoring of Percentage of Methyl Red Cleaved, Degradation Value of N,N-Dimethyl-p-phenylene diamine and o- Aminobenzoic acid, and Growth of Selected Methyl Red- degrading Bacteria by Spectrophotometric Analysis " --- p.68 / Chapter 3.3.2 --- Study of Degrading Products of Methyl Red by Selected Methyl Red-degrading Isolates --- p.71 / Chapter 3.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.73 / Chapter 4. --- Results --- p.74 / Chapter 4.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-dimethyl-p-phenylene diamine-degrading Microbial Isolates " --- p.74 / Chapter 4.1.1 --- "Isolation of Methyl Red-degrading Microbial Isolates from Dye- containing Wastewater, Activated Sludge and Soil " --- p.74 / Chapter 4.1.2 --- Selection of Methyl Red-degrading Microbial Isolates --- p.79 / Chapter 4.1.3 --- "Enrichment of N,N-dimethyl-p-phenylene diamine-degrading Bacteria from Dye-containing Wastewater, Activated Sludge and Soil " --- p.85 / Chapter 4.1.4 --- "Isolation of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.85 / Chapter 4.1.5 --- "Selection of N,N-Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.90 / Chapter 4.1.6 --- "Identification of the Selected Methyl Red-degrading and N,N- Dimethyl-p-phenylene diamine-degrading Bacteria " --- p.90 / Chapter 4.1.7 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.94 / Chapter 4.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.94 / Chapter 4.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.94 / Chapter 4.2.2 --- "Change of UV-Vis Spectra of Methyl Red and N,N-Dimethyl-p- phenylene diamine at Different pH and Matrixes " --- p.108 / Chapter 4.2.3 --- "UV-Vis Spectra and Standard Curves of Methyl Red, N，N- Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.123 / Chapter 4.2.4 --- "HPLC Separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.129 / Chapter 4.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.138 / Chapter 4.3.1 --- "Monitoring of Percentage of Methyl Red Cleaved and Degradation Value of N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid and Growth of Selected Methyl Red- degrading Bacterial Isolates by Spectrophotometric Analysis " --- p.138 / Chapter 4.3.2 --- Study of Degradation Products of Methyl Red by Selected Methyl Red-degrading Isolates by HPLC --- p.175 / Chapter 4.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.175 / Chapter 5. --- Discussion --- p.181 / Chapter 5.1 --- "Isolation, Selection and Characterization of Methyl Red-degrading and N,N-dimethyl-p-phenylene diamine-degrading Microbial Isolates " --- p.181 / Chapter 5.1.1 --- "Isolation and Selection of Methyl Red-degrading Microbes from Dye-containing Wastewater, Activated Sludge and Soil " --- p.181 / Chapter 5.1.2 --- "Isolation and Selection of N,N-Dimethyl-p-phenylene diamine- degrading Microbial Isolates from Dye-containing Wastewater, Activated Sludge and Soil " --- p.183 / Chapter 5.1.3 --- Identification of the Selected Methyl Red-degrading and N，N- Dimethyl-p-phenylene diamine-degrading Bacteria --- p.185 / Chapter 5.1.4 --- Correlationship of Dry Weight and Absorbance of Cells of Selected Methyl Red-degrading Bacterial Isolates --- p.185 / Chapter 5.2 --- "Characterization of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.186 / Chapter 5.2.1 --- "Chemical Stability of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid in 0.05 M phosphate buffer and 0.2MHC1 " --- p.186 / Chapter 5.2.2 --- "Change of UV-Vis Spectra of Methyl Red and N,N-Dimethyl-p- phenylene diamine at Different pH and Matrixes " --- p.187 / Chapter 5.2.3 --- "Change of UV-Vis Spectra of N,N-Dimethyl-p-phenylene diamine in Different Matrixes at Different pH " --- p.187 / Chapter 5.2.4 --- "UV-Vis Spectra and Standard Curve of Methyl Red, N,N- dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.188 / Chapter 5.2.5 --- "HPLC Separation of Methyl Red, N,N-Dimethyl-p-phenylene diamine and o-Aminobenzoic acid " --- p.189 / Chapter 5.3 --- Methyl Red Degradation by Selected Methyl Red-degrading Microbial Isolates --- p.190 / Chapter 5.3.1 --- Effect of Glucose --- p.194 / Chapter 5.3.2 --- Effect of Ethanol --- p.196 / Chapter 5.3.3 --- Effect of Ammonium Sulphate --- p.198 / Chapter 5.3.4 --- Effect of Yeast Extract --- p.199 / Chapter 5.3.5 --- Effect of Phosphate Buffer (pH 7) --- p.200 / Chapter 5.3.6 --- Effect of pH --- p.201 / Chapter 5.3.7 --- Effect of Temperature at Static and Shaking Conditions --- p.203 / Chapter 5.3.8 --- Study of Degradation Products of Methyl Red by Selected Methyl Red-degrading Isolates by HPLC Analysis --- p.206 / Chapter 5.4 --- Degradation of Other Azo Dyes by Selected Methyl Red-degrading Isolates --- p.207 / Chapter 6. --- Conclusion --- p.209 / Chapter 7. --- References --- p.213 / Chapter 8. --- Appendix 1: Composition of Media --- p.222 / Appendix 2: Composition of Buffers --- p.225 / Appendix 3 --- p.228

Leung Bo-Shan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 148-159). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / List of Abbreviations --- p.vi / List of Tables --- p.viii / List of Figures --- p.ix / Chapter 1 --- Introduction / Chapter 1.1 --- Food colorants --- p.1 / Chapter 1.2 --- Caramel --- p.3 / Chapter 1.2.1 --- Classes of caramel --- p.3 / Chapter 1.2.2 --- Toxicological studies of caramel --- p.5 / Chapter 1.3 --- Castanea mollissima --- p.9 / Chapter 1.4 --- Antioxidants --- p.10 / Chapter 1.4.1 --- Background --- p.10 / Chapter 1.4.2 --- Methods used to evaluate the antioxidative activity --- p.12 / Chapter 1.4.2.1 --- DPPH* scavenging method --- p.13 / Chapter 1.4.2.2 --- High performance liquid chromatography (HPLC) --- p.13 / Chapter 1.5 --- Microtox® test --- p.19 / Chapter 1.6 --- Mutatox® test --- p.19 / Chapter 1.7 --- Methods used to evaluate the functions of major organs --- p.20 / Chapter 1.7.1 --- Liver --- p.20 / Chapter 1.7.2 --- Kidneys --- p.23 / Chapter 1.8 --- Toxicology --- p.25 / Chapter 1.8.1 --- Acute toxicity test --- p.25 / Chapter 1.8.2 --- Chronic toxicity test --- p.26 / Chapter 1.9 --- Objective --- p.27 / Chapter 2 --- Materials and Methods --- p.28 / Chapter 2.1 --- Plant materials --- p.28 / Chapter 2.2 --- Sample preparation --- p.28 / Chapter 2.3 --- Pigment characterization --- p.30 / Chapter 2.3.1 --- Stability test --- p.30 / Chapter 2.3.2 --- HPLC separation of CP --- p.31 / Chapter 2.3.3 --- Determination of antioxidative activity with the DPPH* scavenging method --- p.31 / Chapter 2.4 --- Microtox® test --- p.33 / Chapter 2.5 --- Mutatox® test --- p.34 / Chapter 2.6 --- Acute toxicity test --- p.35 / Chapter 2.6.1 --- Animals --- p.35 / Chapter 2.6.2 --- Housing and maintenance --- p.35 / Chapter 2.6.3 --- Experimental design --- p.37 / Chapter 2.6.4 --- Chemicals --- p.39 / Chapter 2.6.5 --- Clinical pathology test --- p.41 / Chapter 2.6.5.1 --- Haematology --- p.41 / Chapter 2.6.5.2 --- Blood chemistry --- p.45 / Chapter 2.6.5.3 --- Urinalysis --- p.55 / Chapter 2.6.6 --- Histological study --- p.57 / Chapter 2.6.7 --- Statistical analysis --- p.57 / Chapter 2.7 --- Chronic toxicity test --- p.59 / Chapter 2.7.1 --- Animals --- p.59 / Chapter 2.7.2 --- Housing and maintenance --- p.59 / Chapter 2.7.3 --- Experimental design --- p.59 / Chapter 2.7.4 --- Chemicals --- p.60 / Chapter 2.7.5 --- Clinical pathology test --- p.61 / Chapter 2.7.5.1 --- Haematology --- p.61 / Chapter 2.7.5.2 --- Blood chemistry --- p.62 / Chapter 2.7.5.3 --- Urinalysis --- p.62 / Chapter 2.7.6 --- Histological study --- p.62 / Chapter 2.7.7 --- Statistical analysis --- p.62 / Chapter 3 --- Results --- p.63 / Chapter 3.1 --- Pigment characterization --- p.63 / Chapter 3.1.1 --- Stability test --- p.63 / Chapter 3.1.2 --- HPLC separation of CP --- p.63 / Chapter 3.1.3 --- Antioxidative activities of CP preparations --- p.63 / Chapter 3.2 --- Microtox® test --- p.65 / Chapter 3.3 --- Mutatox® test --- p.65 / Chapter 3.4 --- Acute toxicity test --- p.66 / Chapter 3.4.1 --- Growth rate --- p.66 / Chapter 3.4.2 --- Food and fluid consumption --- p.66 / Chapter 3.4.3 --- Organ-weight --- p.66 / Chapter 3.4.4 --- Clinical pathology tests --- p.68 / Chapter 3.4.4.1 --- Haematology --- p.68 / Chapter 3.4.4.2 --- Blood chemistry --- p.70 / Chapter 3.4.4.3 --- Urinalysis --- p.76 / Chapter 3.4.5 --- Histological study --- p.76 / Chapter 3.5 --- Chronic toxicity test --- p.77 / Chapter 3.5.1 --- Growth rate --- p.77 / Chapter 3.5.2 --- Food and fluid consumption --- p.77 / Chapter 3.5.3 --- Organ-weight --- p.77 / Chapter 3.5.4 --- Clinical pathology tests --- p.78 / Chapter 3.5.4.1 --- Haematology --- p.78 / Chapter 3.5.4.2 --- Blood chemistry --- p.80 / Chapter 3.5.4.3 --- Urinalysis --- p.82 / Chapter 3.5.5 --- Histological study --- p.82 / Chapter 4 --- Discussion --- p.137 / Chapter 4.1 --- Pigment characterization --- p.137 / Chapter 4.2 --- Toxicological studies of CP --- p.140 / Chapter 5 --- Conclusion --- p.147 / References --- p.148

The aim of this study was to evaluate the influence of two bleaching agents on color of one composite resin (Filtek Z350 XT - 3M ESPE) in the opacities of enamel and dentin, previously subjected to the action of deionized water or red wine. Sixty specimens (sp) were made for each composite resin using a metal matrix with 8 mm diameter and 2 mm thickness. Immediately after polymerization with LED (Emitter Schuster / Santa Maria Rio Grande do Sul, Brasil) for 40 s, the sp were polished with Diamond Pro discs (FGM / Joinvile SC, Brasil), and felt discs with diamond paste (Diamond Excel FGM / Joinvile SC, Brasil), then sp were washed in water and dried. The sp were divided into two groups for each opacity: immersed in red wine or deionized water for 14 days and then divided into three subgroups: one group subjected to bleaching with hydrogen peroxide 35% (Mix One Lot: 043 - Dental Villevie Brasil Ltda), one group submitted to bleaching with carbamide peroxide 16% (Mix Night - Lot: 007 - Dental Villevie Brasil Ltda) and one group not subjected to bleaching. Successive measurements were conducted 24 hours after polishing procedures, after 14 days of immersion on their respective immersion media, and after the action of the bleaching agents, using a spectrophotometer (SP60 EX-Rite / Grand Rapid Michigan, USA), with CIE L* a* b* system. Data were analyzed with t-test, one-way ANOVA, and Tukey (5%). Red wine caused significant color change in the composites in relation to water, and the enamel resin presented greater color change than the dentin resin. Bleaching agents partially removed the pigmentation of the sp which were immersed in wine, and the carbamide peroxide showed more significant results. The bleaching agents did not determine significant results when the sp were immersed in water. Red wine had great influence on the color change of composite resins and water caused no significant color change. The bleaching agents were capable of partial removal of the pigmentation produced by red wine. / Este trabalho teve por objetivo avaliar a influência de dois agentes clareadores sobre a cor de uma resina composta (Filtek Z350 XT 3M ESPE) nas opacidades de esmalte e dentina, previamente submetidas à ação de água deionizada ou vinho tinto suave. Foram confeccionados 60 corpos-de-prova (cps) para cada resina composta utilizando uma matriz metálica com 8 mm de diâmetro e 2 mm de espessura. Imediatamente após a fotoativação com um LED (Emitter Schuster / Santa Maria Rio Grande do Sul, Brasil) por 40s, os cps foram polidos com discos Diamond Pro (FGM / Joinvile SC, Brasil) e disco de feltro com pasta diamantada (Diamond Excel FGM / Joinvile SC, Brasil), lavados em água e secos. Os cps foram divididos em 2 grupos para cada opacidade: imersos em vinho tinto suave ou em água deionizada, por 14 dias e subdivididos em 3 subgrupos: um grupo submetido ao clareamento com peróxido de hidrogênio 35% (Mix One Lot: 043 - Dental Villevie Brasil Ltda), um grupo submetido ao clareamento com peróxido de carbamida 16% (Mix Night - Lot: 007 - Dental Villevie Brasil Ltda) e um grupo não submetido ao clareamento. Sucessivas leituras foram realizadas após 24 horas da confecção dos corpos-de-prova (inicial), após 14 dias de imersão nos respectivos meios; e após a ação de agentes clareadores utilizando um espectrofotômetro (SP60 EX-Rite / Grand Rapid Michigan, USA), com o sistema CIE L* a* b*. Os dados foram submetidos ao Teste t, análise de variância uma via e Tukey (5%). O vinho tinto suave causou significativa alteração de cor nas resinas compostas em relação à água, sendo que, a resina composta de esmalte sofreu maior alteração de cor que a de resina composta de dentina. Os agentes clareadores removeram parcialmente o pigmento dos cps que foram imersos em vinho, sendo que o peróxido de carbamida apresentou resultados mais significativos. Já quando os cps foram imersos em água os agentes clareadores não determinaram resultados relevantes. O vinho tinto suave teve grande influência na alteração de cor das resinas compostas e a água não causou alteração de cor significativa. Os géis clareadores foram capazes de fazer a remoção parcial da pigmentação produzida pelo vinho tinto.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to determine the color stability of aesthetic brackets (plastic and ceramic) when stored in red wine, subjected to daily baths of wine, and immersed in distilled water for different periods. With the aid of a spectrophotometer (SP60 - XRite) and using the CIE L * a * b * system, the initial color parameters and after 15, 30, and 45 days were measured. Brackets of different composition and trademarks were evaluated: Composite (polycarbonate) and Ceramic (polycrystalline ceramic)from Dental Morelli, Maia (polycrystalline ceramic) and Zetta (monocrystalline ceramic)from Eurodonto Orthodontic Products. After the initial color measurements, brackets were divided into 12 groups (n = 10) according to storage media and trademark. The control group remained immersed in distilled water, the wine test group received daily baths of red wine for 15 minutes during the entire period of the study and the immersion test group remained immersed in red wine throughout the study. Repeated readings were performed at 15, 30,and 45 days. Data were submitted to ANOVA and Tukey s test (5%). Color changes were observed in all tested materials, with the greatest change found in group immersioned in red wine, followed by the group subjected to daily baths, and the group stored in distilled water. The polycarbonate showed the greatest color change comparing to ceramics, and the polycrystalline ceramic demonstrated greater color change than monocrystalline ceramic. For all tested groups, the longer the period the greater the changes in color. The type of material and the time in contact with the staining agente had a directly influence in the color stability of brackets. / O presente trabalho teve como objetivo verificar a estabilidade de cor de bráquetes estéticos (plásticos e cerâmicos) quando armazenados em vinho tinto, submetidos a banhos diários de vinho tinto e imerso em água destilada, durante períodos de tempo distintos. Com o uso de um espectrofotômetro (SP60 - X-Rite), empregando o sistema CIE L* a* b*, os parâmetros de cor inicial e após 15, 30e 45 dias foram aferidos. Bráquetes de diferentes composições e marcas comerciais foram avaliados: Composite (policarbonato) e Ceramic (cerâmica policristalina) da Dental Morelli, Maia (cerâmica policristalina) e Zetta (cerâmica monocristalina),da Eurodonto Produtos Ortodônticos. Após a mensuração da cor inicial, os bráquetes foram divididos em 12 grupos (n=10) de acordo com os meios de armazenamento e marca comercial. O grupo controle permaneceu imerso em água destilada, o grupo teste de banho em vinho foi colocado em vinho tinto por 15 minutos diários durante o período do estudo e o grupo teste de imersão permaneceu imerso em vinho tinto durante todo o período dos testes. Sucessivas leituras foram realizadas nos períodos de 15, 30 e 45 dias. Os dados foram submetidos à Análise de Variância e teste de Tukey (5%).Encontrou-se alteração de cor em todos os materiais testados, sendo a maior encontrada na imersão contínua em vinho tinto, seguida do grupo submetido a banhos diários e do grupo em água destilada. O policarbonato sofreu a maior alteração de cor em relação às cerâmicas e a cerâmica policristalina sofreu maior alteração de cor em relação à cerâmica monocristalina. Em tempos mais longos houve maior alteração em todos os grupos. O tipo de material e o tempo de contato com a substância corante influenciaram diretamente na estabilidade da cor dos bráquetes.

The aim of this study was to determine translucency of composite resins formed by different monomers when stored in two distinct environments (immersed in dis tilled water and red wine) and periods of time (immediately after curing, 24h and 30 days). Also two methods for translucency evaluation (Translucency Parameter and Percentage of Opacity) were compared. Three composite resins were tested: one silorane-based (Filtek P90) and two metacrilate-based (Filtek Z350 and Rok). Fourteen specimens (sp) were made for each composite using a metallic matrix with 10 mm of diameter and 2 mm of thickness. Immediately after light curing using a LED (±800mW/cm2) for 40 seconds, sp were polished with Sof-Lex Pop On Orange Series discs and with felt and diamond paste, then sp were washed in water and dried. Immediately after polishing, the initial translucency was measured with the spectrophotometer SP60 - X-Rite using the CIE L * a * b * system. Then the sp of each composite resin was divided into two groups (n = 7) according to the storage media. Successive readings were conducted in periods of 24 hours and 30 days. Data were submitted to ANOVA and Tukey s test (5%) to compare the means of the groups. The silorane-based composite resin showed less translucency changes than metacrilate-based resins, only when stored in wine. In deionized water the modification of P90 was greater than other resins, improving the translucency. All composites presented more alteration when stored in wine than in water, and such variation was higher in longer periods of storage. No differences were found between the methods of evaluation. Both methods of translucency evaluation demonstrated similar results. The translucency of composites was more affected by the red wine than by the water and the longer the period of contact with this substance the greater the modification. The type of monomer seems to be a factor that will influence the translucency changes of composite resins. The variation of translucency can be measured by the two tested methods / O objetivo deste trabalho foi verificar a translucidez de resinas compostas constituídas por diferentes monômeros, quando armazenadas em meios (imersos em água e em vinho tinto suave) e períodos distintos (imediatamente após a fotoativação, 24h e 30 dias). Também foram comparados dois métodos de análise de translucidez (Parâmetro de Translucidez e o Percentual de Opacidade) das resinas compostas. Três resinas compostas foram utilizadas, uma a base de silorano (Filtek P90) e duas a base de metacrilatos (Filtek Z350 e Rok). Foram confeccionados 14 corpos-de-prova (cps) para cada resina composta, utilizando uma matriz metálica com 10 mm de diâmetro e 2 mm de espessura. Imediatamente após a fotoativação com uma fonte de luz LED (±800mW/cm2), por 40s, os cps foram polidos com discos Sof-Lex Pop On e disco de feltro com pasta diamantada, lavados em água e secos com gaze. A translucidez inicial dos cps foi aferida imediatamente após o polimento com o espectrofotômetro SP60 - X-Rite, utilizando o sistema CIE L* a* b*. Os cps de cada resina composta foram divididos em dois grupos (n=7) de acordo com os meios de armazenamento. Sucessivas leituras foram realizadas nos períodos de 24h e 30 dias. Os dados foram submetidos à Análise de Variância e Teste de Tukey (5%). A resina a base de silorano apresentou menor variação de translucidez, que as resinas a base de metacrilatos, apenas, quando armazenada em vinho. Já em água deionizada, a variação da P90 foi maior que nas demais, ficando mais translucida. Todas as resinas apresentaram maior alteração de translucidez, quando armazenadas em vinho do que em água, e esta variação foi maior no período de trinta dias. O tipo de monômero parece ser um fator que irá influenciar a variação da translucidez da resina composta. A variação de translucidez pôde ser aferida pelos dois métodos testados de forma semelhante.

The aim of this study was to evaluate the marginal staining of ceramic laminates cemented with and without the presence of enamel preparation. Thirty-two (32) permanent central incisors were selected and randomly divided into two groups (CP and SP). In group-CP (n = 16) the laminates were bonded to the prepared enamel and in group-SP (n=16) laminates were cemented directly over the intact enamel, with no preparation. The preparation and cementation were standardized and performed by a single operator. Each group was subdivided into two subgroups (n = 8) which correspond to different immersion media - coffee and water ( SPc , SPa , CPc and CPa ). After an immersion period of 10 days, stereomicroscope pictures with 20X of the mesial, distal, cervical and incisal surface of each specimen were made. The interfaces tooth - resin cement - laminate were evaluated by three blind, trained and calibrated examiners. Data were subjected to statistical Kruskal - Wallis and Mann - Whitney analysis. The prepared group as well as the unprepared group showed higher marginal staining when immersed in coffee. When immersed in coffee, the prepared laminates presented more marginal staining then unprepared laminates. But when immersed in water there was no statistically significant difference between the groups. The adhesive interface of ceramic laminates cemented on prepared enamel presented more marginal staining than laminates cemented on intact enamel, with no preparation, after immersion in staining solution. / O objetivo deste trabalho foi avaliar o manchamento marginal de laminados cerâmicos cimentados com e sem a presença de preparo do esmalte. Trinta e dois (32) incisivos inferiores permanentes hígidos foram selecionados e aleatoriamente divididos em dois grupos (CP e SP). No grupo CP (n=16) os laminados foram cimentados sobre o esmalte preparado e no grupo SP (n=16) os laminados foram cimentados diretamente sobre o esmalte intacto, sem preparo. Os preparos e a cimentação foram padronizados e realizados por um único operador. Cada grupo foi subdividido em dois subgrupos (n=8) que correspondem a diferentes meios de imersão café e água (SPc, SPa, CPc e CPa). Após um período de imersão de 10 dias, foram feitas imagens em Estereomicroscópio com aumento de 20X das faces mesial, distal, cervical e incisal de cada corpo de prova. As interfaces dente - cimento resinoso - laminado foram avaliadas por três examinadores cegos, treinados e calibrados. Os dados foram submetidos aos testes estatísticos Kruskal-Wallis e Mann-Whitney. Os corpos de prova imersos no café apresentaram maior manchamento que os imersos na água, tanto no grupo com preparo como no sem preparo. As interfaces dos laminados com preparo mancharam mais do que os sem preparo quando imersos em café. Porém quando imersos em água não houve diferença estatisticamente significante entre os grupos. Pode-se concluir que a interface adesiva de laminados cerâmicos cimentados sobre esmalte preparado apresenta maior manchamento do que os laminados cimentados sobre o esmalte intacto quando submersos em solução corante.

Presente estudo teve como objetivo avaliar a utilização da tecnologia de banda estreita com filtros ópticos (TBE) no rastreamento do carcinoma espinocelular do esôfago (CEC), utilizando como método comparativo a cromoscopia com a solução de Lugol. Trata-se de um estudo prospectivo de teste de diagnóstico, para o qual foram avaliados 129 pacientes do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), com diagnóstico de carcinoma epidermóide de cabeça e pescoço, em programa de rastreamento de tumores secundários, no período de agosto de 2006 a fevereiro de 2007. Os exames de endoscopia convencional, TBE e a cromoscopia com Lugol foram realizados consecutivamente em um mesmo procedimento, e as lesões encontradas foram registradas e submetidas a biópsias. Foram calculados para cada método valores da sensibilidade, especificidade, acurácia, valores preditivos positivos e negativos, valores de verossimilhança positivo e negativo. Foram diagnosticados nove carcinomas superficiais (7%), sendo cinco carcinomas in situ e quatro carcinomas intramucosos, todos detectados pelo TBE e pelo Lugol, porém apenas seis foram diagnosticados pelo exame convencional e destes, nenhum foi menor ou igual a 10 mm. A tecnologia de bandas estreitas com filtros ópticos (TBE) sem magnificação de imagem apresentou resultados superponíveis a cromoscopia com Lugol, método atualmente de escolha para rastreamento do CEC esofágico em grupos de pacientes de alto risco, portadores de tumores de cabeça e pescoço / Background and study aims: The aim of this study was to compare narrow band imaging (NBI) without magnification and chromoendoscopy with Lugols solution for detecting superficial esophageal squamous cell carcinoma in patients with head and neck cancer. Patients and methods: This is a prospective observational study of 129 patients with primary head and neck tumors consecutively referred to the Gastrointestinal Endoscopy Unit of Hospital das Clínicas, São Paulo University Medical School (FMUSP), Brazil, between August 2006 and February 2007. Conventional examinations, NBI and Lugol chromoendoscopy were consecutively performed, and the detected lesions were mapped, recorded and sent for biopsy. The results of the three methods were compared regarding sensitivity, specificity, accuracy, positive predictive value, negative predictive value, positive likelihood value and negative likelihood value. Results: Of the 129 patients, nine (7%) were diagnosed with carcinomas, five of which were in situ and four intramucosal. All carcinomas were detected through NBI and Lugol chromoendoscopy. Only six lesions were diagnosed by conventional examination, all of which were larger than 10 mm. Conclusions: Narrow-band imaging technology with optical filters has high sensitivity and high negative predictive value for detecting superficial esophageal squamous cell carcinomas and produces results comparable to those obtained with 2.0% Lugol chromoendoscopy in patients with head and neck cancer