Anxiety for adverse health effects attributed to dental restorative materials especially dentalamalgam, have been discussed extensively off and on the last 30 years. The possible health effect ofamalgam and health effect of replacements of amalgam, have been extensively studied but theresults are inconclusive and the etiology of the reactions are not entirely elucidated. Furthermore,the question of psychological influence on symptoms attributed to dental restorative materials hasbeen raised and need further examination. The aims of this thesis were to describe the change in health over time for patient with symptomsattributed to their dental materials and to determine whether replacement of their dentalrestorative materials had any impact on their perceived health. Furthermore, to determine anddescribe the personality, self-image, level of psychological symptoms and stress among thesepatients and compare the results with those of healthy controls. Finally, to evaluate regression ofLichenoid Contact Reactions and Oral lichen Planus after replacement of the dental materials. A questionnaire was mailed to 614 patients that had been referred to the School of Dentistry, Umeå,Sweden with symptoms attributed to dental materials. Among these patients a subgroup with orallichen also underwent a clinical examination at follow-up. The result showed that patients with complex symptoms had a more unfavorable long-termprognosis concerning persistent complaints than those with local symptoms only. The oralsymptoms had decreased between baseline and follow-up and the general symptoms had increased.The increase in general symptoms was contradictory since many patients experienced healthimprovement after removal of their dental restorative materials. Concerning personality thepatients was characterized mainly by high persistence and by high fatigability and asthenia as wellas psychosocially learned high self-acceptance. Regarding self-image, both patients with LocalSymptoms Only and patients with Multi Symptoms, scored significantly higher on "spontaneous"and "positive self-image" than the reference group. The Multi symptoms group scored significantlyhigher on psychological symptoms compared to the reference group. However, the Local symptomsgroup did not differ from the references. The remission of oral lesions was after an exchange ofdental materials was seen to a greater extent in patients with Lichenoid Contact Reaction than inpatients with Oral Lichen Planus. Regarding psychological parameters, there were no significantdifferences between the groups. In conclusion symptoms related to dental restorative materials seem to be multi-factorial wheredental, medical, social, and psychological factors may be involved. Patient with complex symptomshave a more unfavorable prognosis than patient with local symptoms only. Patient with symptomsself-related to their dental materials may feel improvement in general health after an exchange ofdental materials. The group of patients seems to represent personalities that could be vulnerable inthe demanding modern society, and the various mental and somatic symptoms can be interpretedas attributed to dental fillings. Patients with Local Symptoms or Multi Symptoms are equalconcerning self-image, they are impulsive with an elevated positive self-image, that can result indifficulties in setting limits. Thus in combination with high demands may result in mental stress.The Multi Symptoms group was more psychologically stressed than the group with Local SymptomsOnly and the references. Therefore, before an exchange of dental materials is commenced inpatients with oral lichenoid lesions, a correct diagnosis is needed.

A radiopacidade é um requisito essencial para a boa qualidade de um material restaurador estético, pois está diretamente relacionada à adaptação marginal. Nosso objetivo foi avaliar a radiopacidade de 28 marcas de resinas fotopolimerizáveis de uso direto existentes no mercado e compará-las com a radiopacidade do esmalte, da dentina e com a espessura equivalente em alumínio. Para tanto, foram confeccionados discos de resina com diferentes espessuras, que foram radiografados pelo método digital direto em conjunto com um penetrômetro de alumínio e com uma secção de dente humano. Pelo processamento digital, pôde-se quantificar o grau de radiopacidade de cada imagem. Nossos resultados mostraram que todos os materiais estudados são tão ou mais radiopacos que o equivalente em alumínio. A dentina não apresentou a mesma radiopacidade de seu equivalente em alumínio em algumas marcas estudadas. Quando a espessura do material não é levada em consideração, a resina Durafill foi a que apresentou radiopacidade menor, incluindo esmalte e dentina. Quando consideramos as diferentes espessuras (0,2; 0,5 e 1mm) a resina Durafill apresentou radiopacidade inferior ao esmalte e à dentina em todas as espessuras. Quando comparada ao alumínio a mesma apresentou radiopacidade inferior na espessura de 0,5mm. A resina Venus apresentou radiopacidade menor que o esmalte na espessura de 1mm, porém semelhante ao mesmo esmalte nas espessuras de 0,2 e 0,5mm. Conclui-se que todas as resinas estão em concordância com a especificação número 27 da American Dental Association. Contudo, pequenas partículas de resinas Durafill e Venus com espessura de 0,2 mm, tanto em excessos quanto em ausências marginais, podem não ser percebidas radiograficamente em restaurações, por apresentarem radiopacidade menor que do esmalte. / The radiopacity is an essential requirement for the good quality of aesthetic restorative materials. We should be aware about the advertisings of radiopacity that many manufacturers do about their materials cause their products, on the market today, do not have the degree of radiopacity suitable for the evaluation of a restoration as the marginal adaptation, the contours and occlusal and the caries recurrence. Our study investigated the radiopacity of 28 brands of direct resins. It was used the method of digital radiographic images acquisition and a software that allowed the digitally measuring of the radiopacity of these materials. It was concluded: the Durafill resin have radiopacity below that of the enamel and that of the dentin, therefore, it is not considered optimal, in the sense of radiopacity, for use in restorations. The resin P90 has limited use in the sense of the outline restoration in radiographs. All the studied materials are as or more radiopaque than their equivalent of aluminum. Dentin, in all studied cases, does not present the same radiopacity of its aluminum equivalent. Dividing this study it is concluded, in the sense of thickness, that is presented by the Durafill resin less radiopacity than that of the enamel and that of the dentin, in three evaluated thicknesses. The resin Venus showed different behaviors in different thicknesses.

>Magister Scientiae - MSc / The aim of this study was to investigate the color stability of two provisional restorative materials used in crown and bridge cases upon exposure to different tea staining solutions and to evaluate the effectiveness of a polishing technique in removing the tea stains from the stained provisional restorative materials.

Alguns estudos têm sido realizados sobre a associação de materiais restauradores odontológicos e soluções antissépticas, pois, em especial a clorexidina (CHX), além dos benefícios apresenta efeitos colaterais. Assim tornam-se necessários estudos de soluções alternativas tão eficazes quanto à CHX, porém sem os efeitos colaterais destas. Neste anseio, foi que se pesquisou Casearia sylvestris (CS) que é uma planta medicinal que oferece benefícios, mas, no entanto, pouco se sabe sobre o efeito desta sobre materiais restauradores estéticos (MRE) e algumas dúvidas permanecem sobre seu potencial antimicrobiano e sua toxidade sobre células. O objetivo deste estudo foi avaliar as propriedades biológicas do óleo essencial (OE) de CS e o efeito deste sobre MRE. Assim, o OE foi obtido por hidrodestilação e caracterizado por Cromatografia a gás acoplada a Espectrometria de massas (CG-EM) e os valores de concentração inibitória e bactericida mínimas foram determinados pelo método de microdiluição frente às espécies Streptococcus (mutans, mitis, sanguinis e salivarius) e Enterococcus faecalis. Avaliou-se também a citotoxidade do OE de CS e da formulação de enxaguatório bucal contendo o OE bioativo em fibroblastos de camundongos. Para a avaliação da rugosidade superficial (RS), cor, microdureza superficial (MS) e a análise qualitativa da superfície (Microscopia Eletrônica de Varredura - MEV) dos MRE submetidos às soluções em estudo, foram confeccionados 60 espécimes (n=10), 30 de cada MRE (resina composta e cimento de ionômero de vidro modificado por resina- CIV), os quais foram subdivididos em 3 grupos para serem submetidos: G1 - CHX, G2 - enxaguatório experimental a base do OE de CS e G3 - Água destilada. As leituras foram realizadas com os aparelhos adequados para cada um dos ensaios, após o polimento dos espécimes e após 24h do término do período experimental. Os resultados obtidos foram avaliados de acordo com os Conceitos da Estatística Clássica, após análise exploratória dos dados. O rendimento do OE obtido foi 0,85mL/100g folhas secas; os constituintes majoritários detectados e identificados no OE foram o β-cariofileno, germacreno-D, biciclogermacreno, δ-cadideno, óxido de cariofileno, espatulenol e α-elemol; o OE e a formulação de enxaguatório desenvolvida apresentaram atividade antimicrobiana significativa frente aos micro-organismos testados, exceto para o OE contra Enterococcus faecalis; o OE nas diferentes concentrações testadas e a formulação de enxaguatório apresentaram citotoxidade frente a fibroblastos gengivais L929 menor estatisticamente que a CHX; a citotoxidade do OE é tempodependente; a formulação desenvolvida proporcionou maior alteração de cor para a resina Z250 do que a CHX e a água destilada, sendo essa mudança em função do Tempo nos parâmetros de cor (L*, a* e b*) analisados isoladamente, enquanto que para o CIV não houve diferença estatisticamente significante para a cor sob as diferentes soluções testadas; as soluções em estudo não tiveram efeito significante sobre a RS da resina composta, enquanto que para o CIV houve um aumento estatisticamente significante na RS quando o mesmo foi submetido a CHX; não houve diferença estatisticamente significante na MS de ambos os MRE testados; e o MEV mostrou deteriorações superficiais principalmente nos corpos de prova de CIV submetidos a CHX. / Researches has been developed associating dental material and mouthwashes, due to the side effects caused presenting in the products, especially chlorhexidine (CHX). Therefore, it becomes necessary studies involving alternative solutions containing the CHX efficacy, but without its collateral effects. Regarding to this, it was studied the specie Casearia sylvestris (CS), a medicinal plant with confirmed benefits, although its effect on dental materials (DM) it is poorly studied (described, talvez fique melhor) and its antimicrobial potencial and cytotoxicity remains controversial. The aim of this study was to evaluate the biological properties of CS essential oil and its effect on DM. The CS essential oil was obtained and characterized through gas chromatography coupled to mass spectrometry (GC-MS). The minimum inhibitory concentration and minimum bactericidal concentration values were determined using the microdilution of Streptococcus species (mutans, mitis, salivarius and sanguinis) and Enterococcus faecalis. It was also evaluated the cytotoxicity on mouse fibroblasts of both essential oil and mouthwash formulation containing the bioactive essential oil. To the superficial roughness, color, superficial microhardness and surface qualitative analysis (Scanning electron microscope SEM) of DM submitted to studied solutions, it was prepared 60 specimens (n = 10), 30 of each DM (composite resin, resin modified glass ionomer- CIV), which were subdivided into 3 groups to the submission: G1 - CHX, G2 - mouthwash containing CS essential oil and G3 - distilled water. The lectures were performed with appropriate equipaments(apparatus, acho que fica melhor): posteriorly specimens polishing and 24h after the experimental period end. The obtained results were evaluated according to the classical statistics concepts, after data exploratory analysis. The yield of essential oil obtained was 0.85 mL/100 g dried leaves; the major constituents detected and identified in the essential oil were β-caryophyllene, germacrene-D, bicyclogermacrene, δ- cadideno, caryophyllene oxide, α-and spathulenol elemol; both mouthrinse containing essential oil as the formulation developed showed significant antimicrobial activity against the tested microorganisms, except Enterococcus faecalis; the different concentrations tested of the essential oil and the mouthwash formulation showed statistically lower cytotoxicity against gingival fibroblasts L929 than CHX; cytotoxicity essential oil is time-dependent; the formulation provided higher color change to resin Z250 when compared with CHX and distilled water, and this change occurred in the factor time of all color parameters (L *, a * and b *) when analyzed alone, while to CIV color the difference was not statistically significant for the different solutions studied, there was a statistically significant increase in CIV surface roughness when submitted to CHX, while to composite resin the difference was not statistically significant; there was no statistically significant difference in microhardness of both restorative materials tested, and SEM showed surface deterioration mostly in the specimens submitted to CHX.

Alguns estudos têm sido realizados sobre a associação de materiais restauradores odontológicos e soluções antissépticas, pois, em especial a clorexidina (CHX), além dos benefícios apresenta efeitos colaterais. Assim tornam-se necessários estudos de soluções alternativas tão eficazes quanto à CHX, porém sem os efeitos colaterais destas. Neste anseio, foi que se pesquisou Casearia sylvestris (CS) que é uma planta medicinal que oferece benefícios, mas, no entanto, pouco se sabe sobre o efeito desta sobre materiais restauradores estéticos (MRE) e algumas dúvidas permanecem sobre seu potencial antimicrobiano e sua toxidade sobre células. O objetivo deste estudo foi avaliar as propriedades biológicas do óleo essencial (OE) de CS e o efeito deste sobre MRE. Assim, o OE foi obtido por hidrodestilação e caracterizado por Cromatografia a gás acoplada a Espectrometria de massas (CG-EM) e os valores de concentração inibitória e bactericida mínimas foram determinados pelo método de microdiluição frente às espécies Streptococcus (mutans, mitis, sanguinis e salivarius) e Enterococcus faecalis. Avaliou-se também a citotoxidade do OE de CS e da formulação de enxaguatório bucal contendo o OE bioativo em fibroblastos de camundongos. Para a avaliação da rugosidade superficial (RS), cor, microdureza superficial (MS) e a análise qualitativa da superfície (Microscopia Eletrônica de Varredura - MEV) dos MRE submetidos às soluções em estudo, foram confeccionados 60 espécimes (n=10), 30 de cada MRE (resina composta e cimento de ionômero de vidro modificado por resina- CIV), os quais foram subdivididos em 3 grupos para serem submetidos: G1 - CHX, G2 - enxaguatório experimental a base do OE de CS e G3 - Água destilada. As leituras foram realizadas com os aparelhos adequados para cada um dos ensaios, após o polimento dos espécimes e após 24h do término do período experimental. Os resultados obtidos foram avaliados de acordo com os Conceitos da Estatística Clássica, após análise exploratória dos dados. O rendimento do OE obtido foi 0,85mL/100g folhas secas; os constituintes majoritários detectados e identificados no OE foram o β-cariofileno, germacreno-D, biciclogermacreno, δ-cadideno, óxido de cariofileno, espatulenol e α-elemol; o OE e a formulação de enxaguatório desenvolvida apresentaram atividade antimicrobiana significativa frente aos micro-organismos testados, exceto para o OE contra Enterococcus faecalis; o OE nas diferentes concentrações testadas e a formulação de enxaguatório apresentaram citotoxidade frente a fibroblastos gengivais L929 menor estatisticamente que a CHX; a citotoxidade do OE é tempodependente; a formulação desenvolvida proporcionou maior alteração de cor para a resina Z250 do que a CHX e a água destilada, sendo essa mudança em função do Tempo nos parâmetros de cor (L*, a* e b*) analisados isoladamente, enquanto que para o CIV não houve diferença estatisticamente significante para a cor sob as diferentes soluções testadas; as soluções em estudo não tiveram efeito significante sobre a RS da resina composta, enquanto que para o CIV houve um aumento estatisticamente significante na RS quando o mesmo foi submetido a CHX; não houve diferença estatisticamente significante na MS de ambos os MRE testados; e o MEV mostrou deteriorações superficiais principalmente nos corpos de prova de CIV submetidos a CHX. / Researches has been developed associating dental material and mouthwashes, due to the side effects caused presenting in the products, especially chlorhexidine (CHX). Therefore, it becomes necessary studies involving alternative solutions containing the CHX efficacy, but without its collateral effects. Regarding to this, it was studied the specie Casearia sylvestris (CS), a medicinal plant with confirmed benefits, although its effect on dental materials (DM) it is poorly studied (described, talvez fique melhor) and its antimicrobial potencial and cytotoxicity remains controversial. The aim of this study was to evaluate the biological properties of CS essential oil and its effect on DM. The CS essential oil was obtained and characterized through gas chromatography coupled to mass spectrometry (GC-MS). The minimum inhibitory concentration and minimum bactericidal concentration values were determined using the microdilution of Streptococcus species (mutans, mitis, salivarius and sanguinis) and Enterococcus faecalis. It was also evaluated the cytotoxicity on mouse fibroblasts of both essential oil and mouthwash formulation containing the bioactive essential oil. To the superficial roughness, color, superficial microhardness and surface qualitative analysis (Scanning electron microscope SEM) of DM submitted to studied solutions, it was prepared 60 specimens (n = 10), 30 of each DM (composite resin, resin modified glass ionomer- CIV), which were subdivided into 3 groups to the submission: G1 - CHX, G2 - mouthwash containing CS essential oil and G3 - distilled water. The lectures were performed with appropriate equipaments(apparatus, acho que fica melhor): posteriorly specimens polishing and 24h after the experimental period end. The obtained results were evaluated according to the classical statistics concepts, after data exploratory analysis. The yield of essential oil obtained was 0.85 mL/100 g dried leaves; the major constituents detected and identified in the essential oil were β-caryophyllene, germacrene-D, bicyclogermacrene, δ- cadideno, caryophyllene oxide, α-and spathulenol elemol; both mouthrinse containing essential oil as the formulation developed showed significant antimicrobial activity against the tested microorganisms, except Enterococcus faecalis; the different concentrations tested of the essential oil and the mouthwash formulation showed statistically lower cytotoxicity against gingival fibroblasts L929 than CHX; cytotoxicity essential oil is time-dependent; the formulation provided higher color change to resin Z250 when compared with CHX and distilled water, and this change occurred in the factor time of all color parameters (L *, a * and b *) when analyzed alone, while to CIV color the difference was not statistically significant for the different solutions studied, there was a statistically significant increase in CIV surface roughness when submitted to CHX, while to composite resin the difference was not statistically significant; there was no statistically significant difference in microhardness of both restorative materials tested, and SEM showed surface deterioration mostly in the specimens submitted to CHX.

Indiana University-Purdue University Indianapolis (IUPUI) / A provisional restoration must fulfill biologic, mechanical, and esthetic requirements. These prostheses should provide comfort, pulp protection, positional stability, occlusal function, hygiene access, esthetics, strength and retention. Methyl-methacrylate acrylic has assumed many appli¬cations in the field of restorative dentistry. However, the material still has deficiencies, such as polymerization shrinkage, pulpal damage associated with exothermic polymerization and susceptibility to fracture. Bis-GMA composites, Bis-acryl composites and visible light-cured urethane dimethacrylate resins have been developed to address these issues. The purpose of this study was to compare the mechanical properties of provisional restorations made from composite resins (Protemp Plus, Luxatemp Solar, Radica, Protemp Crown) to those made of the traditional methacrylate resins (Jet, Snap, High Impact). Six groups of samples, two groups from methacrylate and four groups from composite based materials, were fabricated. Samples from each group were evaluated for microhardness (n=10), flexural strength and flexural modulus (n=20) according to ISO 4049, and fracture toughness (n=20) according to ISO 13586. From each of the six groups, ten samples were tested for flexural strength, flexural modulus and fracture toughness and 5 samples were tested for microhardness. These tests were done after storing at 37°C in a distilled water solution for 7 days followed by thermal cycling (2500 cycles, 5-55°C, 45 s. dwell). Identical sets of samples from each group were used as controls; these were tested after storing for 24 hours in dry conditions. The results were analyzed by two-way ANOVA with material type and aging conditions as the two main variables. Significance level was set at p=0.05. For flexural strength and flexural modules, the higher values were obtained for Radica. Protemp plus (7 days) and Radica (24h) had the highest fracture toughness value. Protemp crown showed the highest surface hardness. The mechanical properties of composite resin were superior.

Quando um dente anterior é restaurado toda uma técnica de proteção ao tecido remanescente e a recuperação funcional do elemento dental podem ser comprometidas se a escolha da cor do material restaurador empregado não for adequada. A familiaridade com as teorias da cor e da interação da luz com a matéria pode ajudar na tarefa de escolha da tonalidade do material restaurador. O desafio na busca de um material restaurador ideal na sua função estética sempre foi obter a translucidez própria do esmalte dental. Contudo, essa translucidez faz com que o material restaurador sofra influência da cor de fundo, que pode ser da cor do material de proteção, ou mais normalmente da cor da dentina. No que tange as atividades de restauração estética odontológico, através deste trabalho foi possível concluir que: 1) A colorimetria pode ser um importante meio na seleção e na comunicação de tonalidades de materiais restauradores; 2) Os resultados obtidos confirmam que a cor de fundo exerce grande influência sobre a cor do resultado final da restauração; e 3) Os guias de tonalidade devem ser reformulados de tal forma que levem em consideração a espessura do material restaurador e a cor de fundo. / When an anterior tooth is restorated, the whole remaining tissue protection technique and functional recuperation of the dental element can be compromised if the choice of the color of the restorative material is not adequate. The familiarity with the color and light interaction with matter theories may help with the task of choosing the restorative material shade. The challenge in searching for an ideal restorative material in its esthetic function was always obtaining the proper translucency of dental enamel. However, this translucency makes the restorative material suffer an influence of the background color, which can be the protection material color or, more commonly, the dentine color. Concerning the odontologic esthetic restorative activities, it was possible to conclude from this work that: 1) Colorimetry can be an important way for the selection and communication of the restorative material shades; 2) The results show that the background color has a large influence on the final color of the restoration; and 3) The shade guides must be reformulated so that it take into consideration the thickness of the restorative material and background color.

Besides the differences in chemical composition, which has a direct influence on the mechanical properties of restorative materials, the various methods of evaluation have generated different results that make it difficult any comparison among their properties. The aim of this study was to determine and compare the flexural strength (FS) of four restorative materials and the influence of the measurement method in such property. Twelve groups (n=15) were obtained and each tested material (Filtek Z350, Epricord, Super Porcelain EX-3 and IPS Empress 2) was submitted to three mechanical tests to assess their FS. For three and four-point bending tests rectangular beams (25x2x2 mm) was used and disc-shaped (12x1,2 mm) was used in the biaxial test. Specimens were submitted to load at the 1 mm/min speed in an EMIC machine, the analysis of stress distribution was performed by 3D finite element analysis and fracture site was visually evaluated. Mean values of FS were obtained from the fracture load of the samples and subjected to statistical analysis. Two-way ANOVA and Tukey's test indicated significant differences between the materials with higher values for IPS Empress 2 (a), followed by Filtek Z350 (b) in all methods, followed by Super Porcelain EX-3 (c) and Epricord (d) in two of three tests. Three-point bending and biaxial tests showed significantly higher values (A), while the four-point bending test was inferior (B). Fracture modes observed correlated with the finite element analysis. Results indicated reliability of all methods, supported by reasonably low coefficients of variation and the highest values of the materials further strengthened in its composition. However, due to lower sensitivity, lower reproducibility (higher coefficient of variation) and greater difficulty of implementation, the four-point bending test seems to be less suitable. / Além das diferenças na composição química, que tem influência direta nas propriedades mecânicas dos materiais restauradores, os diversos métodos de avaliação têm gerado diferentes resultados que dificultam qualquer comparação entre as propriedades dos materiais. O objetivo desse trabalho foi determinar e comparar a resistência flexural (RF) de quatro materiais restauradores e a influência do método na mensuração. Foram obtidos 12 grupos (n=15) sendo que cada material (Filtek Z350, Epricord, Super Porcelain EX-3, e IPS Empress 2) foi submetido a três ensaios de avaliação da RF. Para os ensaios de três e quatro pontos foram obtidas amostras em forma de barras retangulares (25x2x2 mm) e para o biaxial, amostras em forma de disco (12x1,2 mm). Os ensaios foram realizados em máquina EMIC à velocidade de 1 mm/min, a análise da distribuição de tensões foi realizada por elementos finitos em 3D e o local da fratura foi visualmente avaliado. Os valores médios de RF foram obtidos a partir da carga de fratura das amostras e submetidos à análise estatística. Two way ANOVA e teste de Tukey indicaram diferenças significativas entre os materiais com maiores valores para o IPS Empress 2 (a), seguido da resina Filtek Z350 (b) em todos os métodos, seguidos de Super Porcelain EX-3 (c) e Epricord (d) em dois dos três ensaios. Os ensaios de três pontos e biaxial apresentaram valores significativamente maiores (A), enquanto que o de quatro pontos apresentou resultados inferiores (B). Os padrões de fratura observados estão correlacionados com a análise de elementos finitos. Os resultados indicaram confiabilidade de todos os métodos, suportada pelos coeficientes de variação razoavelmente baixos e pelos maiores valores dos materiais mais reforçados em sua composição. Porém, devido a menor sensibilidade, menor reprodutibilidade (maior coeficiente de variação) e maior dificuldade de execução, o ensaio flexural de quatro pontos parece ser o menor indicado. / Mestre em Odontologia

Quando um dente anterior é restaurado toda uma técnica de proteção ao tecido remanescente e a recuperação funcional do elemento dental podem ser comprometidas se a escolha da cor do material restaurador empregado não for adequada. A familiaridade com as teorias da cor e da interação da luz com a matéria pode ajudar na tarefa de escolha da tonalidade do material restaurador. O desafio na busca de um material restaurador ideal na sua função estética sempre foi obter a translucidez própria do esmalte dental. Contudo, essa translucidez faz com que o material restaurador sofra influência da cor de fundo, que pode ser da cor do material de proteção, ou mais normalmente da cor da dentina. No que tange as atividades de restauração estética odontológico, através deste trabalho foi possível concluir que: 1) A colorimetria pode ser um importante meio na seleção e na comunicação de tonalidades de materiais restauradores; 2) Os resultados obtidos confirmam que a cor de fundo exerce grande influência sobre a cor do resultado final da restauração; e 3) Os guias de tonalidade devem ser reformulados de tal forma que levem em consideração a espessura do material restaurador e a cor de fundo. / When an anterior tooth is restorated, the whole remaining tissue protection technique and functional recuperation of the dental element can be compromised if the choice of the color of the restorative material is not adequate. The familiarity with the color and light interaction with matter theories may help with the task of choosing the restorative material shade. The challenge in searching for an ideal restorative material in its esthetic function was always obtaining the proper translucency of dental enamel. However, this translucency makes the restorative material suffer an influence of the background color, which can be the protection material color or, more commonly, the dentine color. Concerning the odontologic esthetic restorative activities, it was possible to conclude from this work that: 1) Colorimetry can be an important way for the selection and communication of the restorative material shades; 2) The results show that the background color has a large influence on the final color of the restoration; and 3) The shade guides must be reformulated so that it take into consideration the thickness of the restorative material and background color.

O objetivo deste estudo in vitro foi avaliar a perda mineral no esmalte adjacente a cavidades preparadas com laser de Er,Cr:YSGG e restauradas com diferentes materiais, liberadores ou não de flúor, após desafio ácido. Cento e vinte blocos de esmalte dental de terceiros molares humanos (4 x4 mm) foram aleatoriamente divididas em 12 grupos (n=10) de acordo com a técnica de preparo: G1- alta-rotação (AR); G2- Laser de Er,Cr:YSGG (3W, 20Hz, 53,05 J/cm2)(65% ar, 55% água); G3- Laser de Er,Cr:YSGG (4 W, 20 Hz, 70,74 J/cm2); G4- Laser de Er,Cr:YSGG (5 W, 20 Hz, 88,43 J/cm2). Cada grupo experimental foi dividido em subgrupos, conforme o material restaurador utilizado: 1- cimento de ionômero de vidro (CIV), 2- cimento de ionômero de vidro resino modificado (CIVRM), 3- sistema adesivo e resina composta (RC). As amostras foram submetidas a desafio ácido (pH 4,8) por 7 dias. As concentrações do íon cálcio nas soluções desmineralizadoras (ppm/mm2), nos diferentes tempos (1, 3 e 7 dias), foram analisadas por espectrofotometria de emissão atômica. Os dados obtidos foram analisados usando os testes estatísticos ANOVA e LSD (?=5%) mostrando haver diferenças significativas entre Técnica e Material Restaurador no tempo total. Os menores valores médios da perda de cálcio foram obtidos nos grupos G2 + CIV, G2 + CIVRM e G1 + CIVRM; os maiores valores foram observados nos grupos de G1 + RC, G4 + CIV e G4 + RC. As restaurações de RC apresentaram maior perda mineral que as de CIV e CIVRM; os preparos com laser utilizando menor radiância (53,05J/cm2) apresentaram significante menor desmineralização que as maiores radiâncias (70,74 e 88,43J/cm2). Nenhuma técnica ou material impediu a desmineralização do esmalte. Os resultados deste estudo in vitro sugerem que a realização de preparos cavitários com laser de Er,Cr:YSGG (53,05J/cm2) restaurados com CIV e CIVRM ou alta-rotação e CIVRM foram efetivos na redução da perda mineral e aumento da resistência ácida do esmalte adjacente as restaurações após desafio ácido, com importante potencial em prevenir lesões de cárie secundária. / The aim of this study was to evaluate the enamel calcium loss around cavities prepared by Er,Cr:YSGG laser and restored with different materials after an acid challenge. One hundred and twenty enamel samples obtained from third molars (4 x 4 mm) were randomly divided in 12 groups (n=10) using different techniques: G1- high-speed drill (HD); G2- Er,Cr:YSGG laser (3W, 20Hz, 53.05 J/cm2)(air 65% - water 55%); G3- Er,Cr:YSGG laser (4 W, 20 Hz, 70.74 J/cm2); G4- Er,Cr:YSGG laser (5 W, 20 Hz, 88.43 J/cm2). Each experimental group was divided in subgroups, according to the restorative material: 1 - glass ionomer cement (GIC), 2 - resin modified GIC (RMGIC), 3 - adhesive system and composite resin (C). Samples were submitted to an acid challenge (4.8 pH) for 7 days. The Demineralizing solutions were analyzed in relation to the calcium ion contend (ppm/mm2), in different times (1, 3 and 7 days), under atomic emission spectrometry. ANOVA and LSD tests were performed (?=5%). There were significant difference between Technique and Restorative Material on Total Time. The lower average values of calcium loss were observed on G2 + GIC, G2 + RMGIC, G1 + RMGIC groups; the higher values were observed on G1 + C, G4 +GIC, G4 + C. The composite resin showed higher calcium loss than RMGIC and GIC. The lased cavities using lower fluence (53.05J/cm2) showed significant reduced demineralization than higher fluences (70.74 and 88.43J/cm2). Neither the techniques nor the restorative materials used were able to prevent the enamel demineralization. The findings of this in vitro study suggest that the Er,Cr:YSGG lased cavities (53.05J/cm2) restored with GIC or RMGIC or conventional drill cavities with RMGIC were effective on reducing the mineral loss and enhancing the enamel acid resistant around restorations after the acid challenge, showing an important potential in preventing secondary caries.