Catelan Anderson, Suzuki Thaís Yumi Umeda, Becker Francisco, Briso André Luiz Fraga, Dos Santos Paulo Henrique
Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, São Paulo, Brazil.
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University, São Paulo, Brazil.
J Investig Clin Dent. 2017 May;8(2). doi: 10.1111/jicd.12203. Epub 2016 Jan 8.
In the present study, we evaluated the influence of surface sealing on color stability and surface roughness of a composite resin after accelerated artificial aging.
Thirty-two specimens of a composite were prepared. After 24 h, the specimens were polished and divided into four groups (n = 8), according to the surface sealant used, including the control, which had no sealant application. Baseline color was measured according to the CIELab system using a reflection spectrophotometer. Surface roughness was determined using a profilometer with a cut-off of 0.25 mm. After these tests, specimens were aged for 252 h in an ultraviolet (UV)-accelerated aging chamber. Color stability was determined by difference between coordinates obtained before and after the aging procedure. Data of color change and roughness were evaluated by anova and Fisher's exact test (α = 0.05).
The results showed that the unsealed group had the highest color change compared to other groups (P = 0.0289), and there was no significant difference between groups sealed with surface sealant (P > 0.05). The artificial aging caused an increase in roughness values independent of the experimental group studied (P = 0.0015).
The sealed composites showed lower color change after UV aging, but all groups showed clinically-acceptable color change, and only liquid polish decreased roughness.
在本研究中，我们评估了表面封闭对复合树脂在加速人工老化后的颜色稳定性和表面粗糙度的影响。
制备了32个复合树脂标本。24小时后，对标本进行抛光，并根据所使用的表面封闭剂分为四组（n = 8），包括未使用封闭剂的对照组。使用反射分光光度计根据CIELab系统测量基线颜色。使用截止值为0.２５mm的轮廓仪测定表面粗糙度。在这些测试之后，将标本在紫外线（UV）加速老化箱中老化252小时。通过老化过程前后获得的坐标之间的差异来确定颜色稳定性。通过方差分析和Fisher精确检验（α = 0.05）评估颜色变化和粗糙度数据。
结果表明，与其他组相比，未封闭组的颜色变化最大（P = 0.0289），使用表面封闭剂封闭的组之间没有显著差异（P> 0.05）。人工老化导致粗糙度值增加，与所研究的实验组无关（P = 0.0015）。
经封闭的复合材料在紫外线老化后的颜色变化较小，但所有组的颜色变化在临床上均可接受，并且只有液体抛光降低了粗糙度。
