Ryan Elizabeth-Ann, Tam Laura E, McComb Dorothy
Faculty of Dentistry, University of Toronto, Toronto, Ontario.
J Can Dent Assoc. 2010;76:a84.
To evaluate the translucency of currently available composites classified by their respective manufacturers as "opaque," "dentin," "body" (or "universal") and "enamel" materials.
Four disk-shaped specimens were produced using a split-ring mould (13 mm in diameter and 2 mm in thickness) from each of 39 proprietary composite restorative materials. Enamel and dentin samples of equivalent thickness were obtained from extracted human teeth. Colour values for lightness (L*), red-green chromatic coordinate (a*) and blue-yellow chromatic coordinate (b*) were recorded against standard white and black backgrounds with a Minolta CR-300 chroma meter under the standard illuminant D65. Translucency parameter values were calculated and compared using analysis of variance and the Tukey test, with significance set at p < 0.05.
A continuum of values for the translucency parameter was obtained, ranging from the most opaque (Filtek Supreme Plus A2D) to the most translucent (Ceram X Duo E2). In general, "opaque" and "dentin" composites yielded relatively low translucency values, "body" (or "universal") composites yielded intermediate values, and "enamel" composites yielded relatively high values. However, the boundaries between these categories were not distinct, and there was some overlap. The mean value of the translucency parameter for human enamel was within the range of values for "enamel" shade composites. The individual values for specimens of human dentin were more variable (i.e., greater standard deviation around the mean) than those for human enamel. The mean value obtained for dentin was intermediate between the ranges for composites with low and intermediate translucency.
The various categories of composite from different manufacturers yielded a wide range of translucency, with minimal distinction between the extremes in adjacent categories. The measured translucency values provided more information than the respective category types. Knowledge of the relative translucency and opacity of different commercial materials can assist clinicians in the choice of composite for clinical use.
评估目前市售的分别被各自制造商归类为“不透明”“牙本质”“主体”（或“通用型”）和“釉质”材料的复合树脂的透明度。
使用裂环模具（直径13毫米，厚度2毫米）从39种专利复合树脂修复材料中各制作4个圆盘形试件。从拔除的人牙中获取厚度相当的釉质和牙本质样本。在标准照明体D65下，使用美能达CR - 300色度仪，针对标准白色和黑色背景记录明度（L*）、红 - 绿色度坐标（a*）和蓝 - 黄色度坐标（b*）的颜色值。使用方差分析和Tukey检验计算并比较透明度参数值，显著性设定为p < 0.05。
获得了透明度参数的一系列值，范围从最不透明的（Filtek Supreme Plus A2D）到最透明的（Ceram X Duo E2）。一般来说，“不透明”和“牙本质”复合树脂产生相对较低的透明度值，“主体”（或“通用型”）复合树脂产生中等值，“釉质”复合树脂产生相对较高的值。然而，这些类别之间的界限并不明显，存在一些重叠。人釉质透明度参数的平均值在“釉质”色复合树脂的值范围内。人牙本质试件的个体值比人釉质的更具变异性（即平均值周围的标准差更大）。牙本质获得的平均值介于低透明度和中等透明度复合树脂范围之间。
不同制造商的各类复合树脂具有广泛的透明度，相邻类别极端值之间的差异极小。测得的透明度值比各自的类别类型提供了更多信息。了解不同市售材料的相对透明度和不透明度可为临床医生选择临床使用的复合树脂提供帮助。
