ObjectiveTo evaluate, in vitro, the shear bond strength presented by three brands of polycrystalline ceramic brackets and one brand of metallic bracket; verify the adhesive remnant index (ARI) after the tests, and analyze, through scanning electron microscopy (SEM) the enamel surface topography after debonding, detecting the release of mineral particles. MethodsSixty bovine lower incisors were used. Three ceramic brackets (Allure®, InVu®, and Clarity®) and one metallic bracket (Geneus®) were bonded with Transbond XT®. Kruskal-Wallis's test (significance level set at 5%) was applied to the results of share bond and ARI. Mann Whitney's test was performed to compare the pairs of brackets in relation to their ARI. Brown-Forsythe's test (significance level set at 5%) was applied to the results of enamel chemical composition. Comparisons between groups were made with Games-Howell's and the Post-hoc tests. ResultsNo statistically significant difference was observed in relation to the shear bond strength loads. Clarity® brackets were the most affected in relation to the surface topography and to the release of mineral particles of enamel (calcium ions). ConclusionWith regard to the ARI, there was a prevalence of score 4 (40.4%). As for enamel surface topography, the Geneus® bracket was the only one which did not show superficial tissue loss. The InVu® and Clarity® ones showed cohesive fractures in 33.3% and the Allure® in 50%, the latter being the one that presented most fractures during removal.

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Objetivo: Determinar os índices de erro e de discrepância de medições realizadas em modelos ortodônticos em acrílico com dentes de estoque em oclusão dentária e maloclusão, utilizando paquímetro digital e avaliar a influência do tempo de experiência profissional na exatidão das medições. Método: Duas medições, com um intervalo mínimo de 30 dias, foram realizadas por 30 alunos de graduação em Odontologia da FO da UFJF, 12 alunos do curso de especialização em Ortodontia da FO da UFJF e 6 professores do curso de especialização em Ortodontia da UFJF. Após a realização das medidas, as médias das dimensões utilizadas no estudo foram obtidas por grupo. A análise estatística utilizada lançou mão do teste t de Student, do ANOVA e do teste de Tukey. Resultados: Erros sistemáticos foram observados na oclusão dentária entre os alunos da especialização e na maloclusão entre os professores da especialização e os alunos da graduação. Discrepâncias de medidas foram observadas na oclusão dentária e na maloclusão entre os alunos da especialização e os da graduação. Erros de medidas foram encontrados na oclusão dentária entre os alunos da graduação e os da especialização. Erros de medidas foram encontrados na maloclusão entre os professores da especialização e os alunos da graduação. Conclusão: O tempo de experiência profissional teve influência significativa nas medições, pois se verificou que o número de erros sistemáticos e discrepâncias de medidas foi maior no grupo de menor experiência, isto é, alunos de graduação, e menor no grupo de maior experiência, grupo de professores da especialização.Viés (Epidemiologia); Medidas; Oclusão Dentária; Maloclusão -Diagnóstico.Objective: To establish the error and discrepancy rates of measurements performed in orthodontic models with acrylic teeth in occlusion and malocclusion using a digital caliper and to assess the influence of the time of professional experience on the accuracy of the measurements. Method: Two measurements with a minimum interval of 30 days between them were made by 30 undergraduate students and 12 graduate students and 6 teachers from the Specialization Course in Orthodontics at the Dental School of the Federal University of Juiz de Fora (UFJF), Juiz de Fora, MG, Brazil. After performing the measurements, the mean values were calculated for each group. Data were analyzed statistically by the Student's t-test, ANOVA and Tukey's test. Results: Systematic errors in the measurements taken in occlusion were observed for the specialization course students, while for the specialization course teachers and undergraduate students systematic errors were observed in malocclusion. Measurement discrepancies were observed in occlusion and malocclusion among the specialization course and undergraduate students. Measurement discrepancies were observed in malocclusion among the specialization course teachers and graduation students. Conclusion: The time of professional experience had significant influence on the measurements since a larger number of systematic errors and measurement d...

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