Pozzobon Roselaine Terezinha, Bohrer Thaís Camponogara, Fontana Patrícia Eliana, Durand Leticia Brandão, Marquezan Marcela
Gen Dent. 2017 Nov-Dec;65(6):e9-e12.
Polishing techniques are known to enhance the longevity and appearance of composite resin restorations. However, the influence of the timing of polishing on the final results of a restoration is not well documented. The aim of this study was to determine the effect of immediate and delayed polishing on the color stability of a composite resin. Sixty composite resin specimens were fabricated and randomly divided into 2 groups according to immersion solutions: group 1, deionized water (control); and group 2, coffee (as staining solution). The groups were further divided according to polishing time periods (immediate, 1 day, 7 days, 14 days, and 21 days). The polishing was performed by 1 calibrated operator using a sequence of aluminum oxide discs with different granulations. Color measurements were assessed at baseline and after a 48-hour immersion in the assigned medium by a reflection spectrophotometer, according to CIE Lab* parameters. The data were submitted to an analysis of variance (ANOVA) and the post hoc Tukey test at a significance level of 0.05. The ANOVA showed that the immersion solutions had a statistically significant difference (α = 0.05) on color stability. The composite resin color stability was not influenced by the timing of polishing, and all subgroups showed clinically unacceptable discoloration after exposure to coffee. Thus, with regard to color stability, the timing of final polishing may be established according to the preferences of the clinician.
已知抛光技术可提高复合树脂修复体的使用寿命和外观。然而，抛光时机对修复最终效果的影响尚无充分文献记载。本研究的目的是确定即时抛光和延迟抛光对复合树脂颜色稳定性的影响。制作了60个复合树脂标本，并根据浸泡溶液随机分为2组：第1组，去离子水（对照组）；第2组，咖啡（作为染色溶液）。根据抛光时间段（即时、1天、7天、14天和21天）将各组进一步细分。由1名经过校准的操作人员使用一系列不同粒度的氧化铝盘进行抛光。根据CIE Lab*参数，在基线时以及在指定介质中浸泡48小时后，用反射分光光度计评估颜色测量值。数据进行方差分析（ANOVA）和事后Tukey检验，显著性水平为0.05。方差分析表明，浸泡溶液对颜色稳定性有统计学显著差异（α = 0.05）。复合树脂的颜色稳定性不受抛光时机的影响，所有亚组在接触咖啡后均出现临床上不可接受的变色。因此，就颜色稳定性而言，最终抛光的时机可根据临床医生的偏好确定。
