Department of Dental and Biomedical Materials Science, Unit of Basic Medical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan.
Dent Mater. 2011 Feb;27(2):165-72. doi: 10.1016/j.dental.2010.10.001. Epub 2010 Nov 4.
The study was conducted to compare the optical parameters of VM7(®) M-shade base dentin ceramics (VITA, Germany) for all ceramic restorations to the chemical composition across the 3D-MASTER(®) shade system.
Three disc samples, 13 mm diameter and 1.4 mm thickness, were produced for each M-shade following the manufacturer's instructions. Each disc was ground and polished to a thickness of 1.0 mm. Spectral light transmittance and reflectance data were recorded in the visible spectrum under the standard illuminant D65 and 2° observer at 10 nm intervals by using a computer-controlled spectrophotometer. Opacity, translucency and opalescence parameters were determined for each sample.
(1) Spectral transmittance and reflectance in the short-wavelength range systematically decreased with increasing chroma number (M1, M2, M3) when compared within the same value (lightness) group. (2) Spectral transmittance and reflectance decreased systematically across the whole visible spectrum with increasing value group number when compared within the same chroma group. (3) Analysis of relationship between chemical composition and various optical parameters for all the samples showed the significant contribution of ZrO₂ and Y₂O₃ substances to optical properties of the present material.
Systematic variations in optical properties of VM7(®) M-shade base dentin ceramics were observed throughout the 3D-MASTER(®) shade system and were suggested to be caused by the fine structure of the sample which can interfere with shorter wavelengths in the visible spectrum.
本研究旨在比较 VM7(®) M 色调基底牙本质陶瓷（VITA，德国）的光学参数与 3D-MASTER(®) 比色系统的化学成分。
按照制造商的说明，为每个 M 色调制作三个直径为 13 毫米、厚度为 1.4 毫米的圆盘样本。每个圆盘都被研磨和抛光至 1.0 毫米的厚度。使用计算机控制分光光度计，在标准光源 D65 和 2°观察者下，以 10nm 的间隔记录可见光光谱中的光谱光透射率和反射率数据。为每个样本确定不透明度、半透明度和乳光参数。
(1) 在同一明度组内，随着色度数（M1、M2、M3）的增加，短波长范围内的光谱透射率和反射率系统地降低。(2) 在同一色度组内，随着可见光光谱的整个范围的数值组号的增加，光谱透射率和反射率系统地降低。(3) 对所有样本的化学成分与各种光学参数之间的关系进行分析表明，ZrO₂和 Y₂O₃物质对本材料的光学性能有显著贡献。
在整个 3D-MASTER(®) 比色系统中观察到 VM7(®) M 色调基底牙本质陶瓷光学性能的系统变化，这被认为是由于样品的精细结构干扰了可见光光谱中的较短波长。
