934 resultados para self-etching adhesive system


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The anterior adhesive system of the oncomiracidium and adult of Merizocotyle icopae (Monogenea: Monocotylidae) were compared. The oncomiracidium has one ventrally placed aperture on either side of the head near the anterior extremity. In the adult, there are three ventrally placed apertures on either side of the head region. Both systems have three types of electron-dense secretory bodies opening into each aperture. A rod-shaped secretion (S1) and a small electron dense ovoid secretion (S2) are common to larvae and adults. The third secretion type differs: in adults, it is a large, spherical (S3) type but in larvae, it is an ovoid (S4) body. S4 bodies do occur in adults, but appear to be secreted as a general body secretion. An additional anteromedian secretion (S5) is also present in the oncomiracidium, but is not secreted into the anterior apertures. Homology and function of secretions are discussed.

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Aim: To evaluate the dislocation resistance of the quartz fiber post/cement/dentin interface after different adhesion strategies. Methods: Forty bovine lower central incisors were selected and prepared with K-files using the step-back technique, and irrigated with 3 mL of distilled water preceding the use of each instrument. Prepared teeth were stored at 37ºC and 100% humidity for 7 days. The roots were prepared and randomized into 4 groups. The quartz fiber post was cemented with an adhesion strategy according to the following groups: GBisCem- BISCEM; GOneStep±C&B- One Step ± C&B; GAllBond±C&B- AllBond3 ± C&B; GAllBondSE±C&B- AllBondSE ±C&B with a quartz fiber post. Cross-sectional root slices of 0.7 mm were produced and stored for 24 h at 37° C before being submitted to push-out bond strength. Results: The mean and standard deviation values of dislocation resistance were GBisCem: 1.12 (± 0.23) MPa, GOneStep±C&B: 0.81 (± 0.31) MPa, GAllBond±C&B: 0.98 (± 0.14) MPa, and GAllBondSE±C&B: 1.57 (± 0.04) MPa. GAllBondSE±C&B showed significantly higher values of dislocation resistance than the other groups. Conclusions: Based on this study design, it may be concluded that adhesion strategies showed different results of quartz post dislocation resistance. Simplified adhesive system with sodium benzene sulphinate incorporation provided superior dislocation resistance.

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The purpose of this study was to evaluate the influence of an additional Er:YAG laser conditioning step after laser cavity preparations, on the microleakage of class V composite restorations. Forty-eight bovine incisors were randomly divided into four groups: G1(control) cavities prepared with bur, G2- cavities prepared with laser (400 mJ/2 Hz), G3-cavities prepared and subsequently conditioned with Er:YAG laser (60 mJ/2 Hz); G4-idem for G3, but the laser conditioning was carried out without water-spray. All the cavities were restored using Clearfill SE Bond (R) and Z-250 (R) composite resin. The samples were thermal cycled for 700 cycles and then immersed in 50% silver nitrate solution. The sectioned restorations were exposed to a photoflood lamp to reveal silver nitrate penetration. The Kruskal-Walis one-way analyses of variance test and post hoc Wilcoxon pair-wise comparison were used to compare microleakage degrees. At the gingival margin G2 showed a lower microleakage mean than the control bur-prepared cavities (p = 0.0003). At occlusal margins there were no statistically significant differences between the groups (p = 0.28). It may be concluded that Er:YAG laser class V cavity preparations do not need to be followed by an additional laser conditioning step to result in levels of microleakage similar to or lower than those obtained after bur preparations. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 87B: 538-543, 2008

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Purpose: More than five hundred million direct dental restorations are placed each year worldwide. In about 55% of the cases, resin composites or compomers are used, and in 45% amalgam. The longevity of posterior resin restorations is well documented. However, data on resin composites that are placed without enamel/dentin conditioning and resin composites placed with self-etching adhesive systems are missing. Material and Methods: The database SCOPUS was searched for clinical trials on posterior resin composites without restricting the search to the year of publication. The inclusion criteria were: (1) prospective clinical trial with at least 2 years of observation; (2) minimum number of restorations at last recall = 20; (3) report on dropout rate; (4) report of operative technique and materials used; (5) utilization of Ryge or modified Ryge evaluation criteria. For amalgam, only those studies were included that directly compared composite resin restorations with amalgam. For the statistical analysis, a linear mixed model was used with random effects to account for the heterogeneity between the studies. P-values under 0.05 were considered significant. Results: Of the 373 clinical trials, 59 studies met the inclusion criteria. In 70% of the studies, Class II and Class I restorations had been placed. The overall success rate of composite resin restorations was about 90% after 10 years, which was not different from that of amalgam. Restorations with compomers had a significantly lower longevity. The main reason for replacement were bulk fractures and caries adjacent to restorations. Both of these incidents were infrequent in most studies and accounted only for about 6% of all replaced restorations after 10 years. Restorations with macrofilled composites and compomer suffered significantly more loss of anatomical form than restorations with other types of material. Restorations that were placed without enamel acid etching and a dentin bonding agent showed significantly more marginal staining and detectable margins compared to those restorations placed using the enamel-etch or etch-and-rinse technique; restorations with self-etching systems were between the other groups. Restorations with compomer suffered significantly more chippings (repairable fracture) than restorations with other materials, which did not statistically differ among each other. Restorations that were placed with a rubber-dam showed significantly fewer material fractures that needed replacement, and this also had a significant effect on the overall longevity. Conclusion: Restorations with hybrid and microfilled composites that were placed with the enamel-etching technique and rubber-dam showed the best overall performance; the longevity of these restorations was similar to amalgam restorations. Compomer restorations, restorations placed with macrofilled composites, and resin restorations with no-etching or self-etching adhesives demonstrated significant shortcomings and shorter longevity.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Ciências Odontológicas - FOAR

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Ciências Odontológicas - FOAR

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O objetivo deste ensaio clínico randomizado foi avaliar o comportamento clínico das restaurações adesivas, usando um adesivo convencional de três passos (CTP), um adesivo autocondicionante de um passo (AUP) e uma técnica simplificada da adesão úmida por etanol (AUET) antes da aplicação de uma resina composta em lesões cervicais não-cariosas. Noventa e três restaurações (31 para cada grupo) foram realizadas em 17 pacientes por um único operador. Nenhum preparo cavitário foi realizado. Depois de 6 e 12 meses, as restaurações foram avaliadas por 2 examinadores previamente treinados, utilizando critérios de Ryge modificados para retenção (kappa=1,00) e adaptação/manchamento marginal (kappa=0,81), e os resultados foram analisados pelos testes Exato de Fisher e Kruskal-Wallis, respectivamente. Não foram observadas diferenças significativas entre os grupos aos 6 e 12 meses para qualquer um dos critérios avaliados (p≥0,05). A análise intra-grupo feita pelos testes Q de Cochran (para retenção) e Wilcoxon (para adaptação/manchamento marginal) revelou diferenças significativas entre os intervalos de tempo baseline/12 meses para a adaptação marginal no AUP (p=0,0180) e manchamento marginal no CTP (p=0,0117). A análise de sobrevivência para o critério retenção realizada utilizando o teste de log-rank não apresentou diferenças significantes (p≥0,05). As restaurações feitas utilizando a técnica simplificada da adesão úmida por etanol comportaram-se igualmente às outras estratégias adesivas empregadas.

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Objective: The aim of this study was to evaluate the 2-year clinical performance of class II restorations made with a composite resin with two different viscosities.Methods: 47 patients received two class II restorations (n = 94), one made with GrandioSO (conventional viscosity CV), and the other with GrandioSO Heavy Flow (flowable viscosity FV), subjecting both materials to the same clinical conditions. The self-etching adhesive Futurabond M was used for all restorations. The composites were inserted using the incremental technique. The restorations were evaluated using the modified USPHS criteria according to the periods: baseline, 6 months, 1 year and 2 years after restorative procedures.Results: After 24 months, 40 patients attended the recall and 78 restorations were evaluated. In all periods, no secondary caries was observed. After 6 months, there were slightly overall changes of scores for most parameters. After 24 months, the higher number of changes from score Alfa to Bravo was observed for marginal discolouration (32.5% CV and 39.5% FV) and colour match (15% CV and 31.6% FV), followed by proximal contact (25% CV and 23.7% FV) and marginal adaptation (20% CV and 21.1% FV). For wear, surface texture and postoperative sensitivity the changes were very small. Just two restorations were lost during the 24-month follow up. Less than 5% of all restorations showed postoperative sensitivity. Chi-square test showed no significant differences between the two materials for all parameters analysed.Conclusion: After 2 years of clinical service, no significant differences were observed between GrandioSO conventional and GrandioSO Heavy Flow for the parameters analysed. Both materials provided acceptable clinical behaviour in class II restorations. Clinical Significance: This study presents the possibility of using a flowable composite with high filler content, for performing class II restorations. (C) 2014 Elsevier Ltd. All rights reserved.

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A adesão longitudinal continua a representar um dos maiores desafios da Odontologia moderna. Uma nova proposta para o estabelecimento do equilíbrio da adesão aos tecidos dentários surge, baseada na observação dos resultados obtidos com a tecnologia Grander para revitalização da água. Objetiva-se com o estudo verificar a influência dessa tecnologia nas propriedades físicas de dois sistemas adesivos (convencional e autocondicionante) à partir da medição da tensão superficial e do ângulo de contato; e avaliar a formação e a qualidade da camada híbrida em dentina humana e bovina. A tensão superficial de quatro diferentes líquidos (água, Single Bond- 3M, Primer do Clearfil SE Bond -Kuraray, e Bond do Clearfil SE-Kuraray), foi medida antes e após a modificação pelo procedimento Grander em aparelho goniômetro (Ramé-hart). O ângulo de contato com três substratos distintos (placa de titânio, dentina humana e dentina bovina), foi medido para os quatro líquidos também antes e após a modificação pelo procedimento Grander, também em goniômetro. A formação e qualidade da camada híbrida, foi avaliada em MEV, a partir da confecção de corpos de prova dos substratos humano e bovino, devidamente embutidos, preparados em lixas de variada granulação até a exposição de dentina, submetidos ao procedimento adesivo (SB ou CSEB) normal ou grander modificado, recebendo ao final dupla camada de resina composta Z250-3M, fotopolimerizada por 40s. Após armazenamento em estufa bacteriológica por 24h, os procedimentos para análise ao MEV foram realizados (fixação, desidratação, secagem e metalização). A estatística de Análise de Variância ANOVA e Teste de Tukey 5% revelou que: houve redução estatisticamente significante da tensão superficial para todos os líquidos Grander modificados; houve redução estatisticamente... (Resumo completo, clicar acesso eletrônico abaixo)