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Objective: The aim of the present study was to evaluate the color stability of Filtek Z350 XT, Filtek Z250 XT, Z100 resin composites and Transbond XT orthodontic resin, all used in orthodontic attachments, when immersed in popular beverages. Methods: Thirty disk-shaped specimens of each resin composite (2 x 5mm) were manufactured and randomly divided into six groups according to immersion solutions: coffee, red wine, white wine, regular beer, dark beer and deionized water (control). The specimens were fully immersed in each of the solutions for six days at 37°C, representing approximately six months of consumption. The color measurements were evaluated by a reflection spectrophotometer, at baseline (before immersion) and after staining. L*a*b* coordinates were measured and the color change (ΔE00) was calculated using the CIEDE2000 formula. The data were analyzed by ANOVA/Tukey tests at a significance level of 0.05. Results: The resin composites immersed in white wine and regular beer showed either imperceptible or clinically acceptable ΔE00, and no difference from the control group (p= 0.4449 and p= 0.467 respectively). Immersion in coffee and red wine were considered clinically unacceptable and were significantly different from the control group (p= 0.0028 and p= 0.0475 respectively). Conclusion: Based on the results of the present study, the consumption of coffee and red wine may cause color change of the resin composite attachments above the visual acceptability threshold, and impair aesthetics during treatment.

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Introduction: Orthodontic mini-implants (MI) are a reliable alternative to provide temporary orthodontic anchorage. Prior to miniscrew insertion, the best approach would be to evaluate each possible insertion site and measure the cortical bone thickness, and verify whether it would provide adequate primary stability. Objective: This study aimed to evaluate the difference in cortical bone thickness in areas of mini-implants insertion in patients of different ages, by means of cone beam computed tomography (CBCT). Methods: The sample of this retrospective study was composed of 123 CBCT scans, which were used to measure cortical bone thickness in the buccal and palatal inter-radicular space in the mesial region of the first permanent molars. These measures were compared by using the Student’s t-test, ANOVA/Tukey tests, and Linear regression between male and female subjects, from 12 to 30 years old. Results: No significant difference was found in cortical bone thickness between sex, race and sagittal facial patterns. Significantly higher measurement values were observed in patients older than 12 years of age at all sites evaluated. The coefficient β at the adjusted linear regression analysis showed that at each increment in age, mean cortical thickness values increased by 0.06mm in the mandible, 0.03mm in the buccal region and 0.02mm in the palatal region of the maxilla. Conclusions: The increase in cortical bone thickness was positively associated with age; that is, the more advanced the patient’s age was, the less chance there was of failure due to primary stability.

<p><strong>Introdução:</strong> A proposta deste estudo foi comparar medidas cefalométricas, lineares e angulares, obtidas de cefalogramas sobre telerradiografias de perfil digitais e reconstruções tomográficas, no plano médio sagital, a partir da tomografia computadorizada de feixe cônico (TCFC). <strong>Materiais e métodos:</strong> Foram selecionadas 108 documentações iniciais de pacientes ortodônticos que continham telerradiografia de perfil digital e tomografia computadorizada de feixe cônico. Para reconstrução tomográfica a largura da base do osso nasal foi adotada como padrão para definição da espessura a ser utilizada. O examinador determinou 17 pontos anatômicos no plano médio sagital para a obtenção de 16 medidas cefalométricas utilizando o Dolphin Imaging Cephalometric and Tracing Software sobre os dois exames analisados. <strong>Resultados:</strong> A análise de reprodutividade do examinador foi feita através do coeficiente de correlação intraclasse (ICC) e constatou-se excelente reprodutibilidade (ICC <span style="text-decoration: underline;">&gt;</span> 0,75) para todas as medidas cefalométricas utilizadas. A média das medidas cefalométricas no plano médio sagital, dos dois tipos de exames, foram submetidas ao teste t pareado e ao teste de Wilcoxon quando não foi obtida normalidade dos dados. Do total de medidas analisadas 9 (nove) foram diferentes estatisticamente, entre os dois grupos: SNA, SNB, SND, 1.NA, S-L, N-Me e SN apresentaram valores de p&lt;0,01 enquanto Pog-NB e S-Li apresentaram valor de  p&lt;0,05.  <strong>Conclusões:</strong> O estudo mostrou que houve diferenças significativas entre as medidas cefalométricas no plano médio sagital obtidas a partir da telerradiografia digital e a tomografia computadorizada de feixe cônico quando utilizada a base do osso nasal como referência de espessura para a reconstrução tomográfica. </p>