Department of Dental Materials and Prosthodontics, School of Dentistry of Araçatuba, São Paulo State University, Araçatuba, SP, Brazil.
Braz Oral Res. 2009 Apr-Jun;23(2):144-8. doi: 10.1590/s1806-83242009000200009.
One of the greatest challenges faced by buccomaxillofacial prosthetists is to reproduce the patient's exact skin color and provide adequate esthetics. To reach this objective, professionals must use materials with easy characterization and that maintain color over long periods of time. The objective of this study was, thus, to evaluate the color stability of two types of silicones, Silastic 732 and Silastic MDX4-4210. Twenty-four test specimens were made from each type of silicone and were divided into a colorless group and groups intrinsically pigmented with ceramics, cosmetics or iron oxide. The specimens were submitted to an accelerated system of aging for non-metallic materials. Readings were carried out initially and after periods corresponding to 163, 351, 692 and 1,000 hours of aging, using a reflection spectrophotometer analysis, and color alterations were calculated by the CIE Lab* system. The data were submitted to variance analysis and Tukey's test at a 5% level of probability. The results demonstrated that, irrespective of the period of time analyzed, all the materials underwent some type of chromatic alteration (DeltaE > 0). The test specimens made with Silastic 732 and MDX4-4210, without pigmentation, presented the lowest color alteration values after 1,000 hours of aging. Of the pigments, ceramic presented the lowest color alteration values and cosmetic powder presented the highest values. Thus, it may be concluded that the materials without the incorporation of pigments presented similar color alteration values, and did not differ statistically. The cosmetic powder used in this study was the pigment that most altered the color of the test specimens.
颌面赝复体制作面临的最大挑战之一是再现患者确切的肤色并提供足够的美观。为了实现这一目标，专业人员必须使用易于描述且颜色能长时间保持的材料。因此，本研究的目的是评估两种硅橡胶（Silastic 732 和 Silastic MDX4-4210）的颜色稳定性。从每种硅橡胶中制作了 24 个测试样本，并将其分为无色组和内在着色为陶瓷、化妆品或氧化铁的组。将样本置于非金属材料加速老化系统中。在初始和老化 163、351、692 和 1000 小时后，使用反射分光光度计分析进行读数，并通过 CIE Lab*系统计算颜色变化。将数据提交给方差分析和 Tukey 检验，置信水平为 5%。结果表明，无论分析的时间段如何，所有材料都经历了某种类型的变色（DeltaE > 0）。未着色的 Silastic 732 和 MDX4-4210 测试样本在老化 1000 小时后呈现出最低的颜色变化值。在这些颜料中，陶瓷呈现出最低的颜色变化值，而化妆品粉末呈现出最高的颜色变化值。因此，可以得出结论，未加入颜料的材料呈现出相似的颜色变化值，且在统计学上没有差异。本研究中使用的化妆品粉末是最能改变测试样本颜色的颜料。
