不同厚度IPS Empress玻璃陶瓷色遮蔽能力研究

A Pilot Study on the Color Masking Ability of IPS Empress Glass-ceramic with Different Thickness

探讨不同厚度的IPS Empress玻璃陶瓷的色遮蔽能力。制作直径10 mm、厚度分别为0.5 mm、1.0 mm、1.5mm和2.0 mm的IPS Empress dentin玻璃陶瓷试件(A2色)各5个,将不同厚度的试件分别置于黑色背景和白色背景上,用PR-650分光光度仪对试件中央区域进行颜色测量,计算每一厚度的色差和对比度,对数据进行统计学分析。结果表明:不同厚度的IPS Empress玻璃陶瓷的色差和对比度有显著性差异(P<0.01);随着试件厚度的增加,色差显著减小,对比度显著增大。IPS Empress玻璃陶瓷的厚度对其色遮蔽能力有显著影响,临床上选择IPS Empress玻璃陶瓷修复体时应考虑此影响。

The purpose of this study was to investigate the color masking ability of IPS Empress glass-ceramic with different thickness. Four groups of disk-shaped liPS Empress glass-ceramic specimens （10 mm in diameter and 0.5, 1.0, 1.5, or 2.0 mm in thickness, A2 shade） were fabricated, five disks per group. Color changes of each specimen were measured with a spectrophotometer against black and white backgrounds, respectively. △E values and contrast ratio values of specimens were calculated. The data were analyzed with one-way ANOVA and Tukey HSD test （ a = 0.01 ）. There were significant differences among the △E values and contrast ratio values of the specimens with different thickness （P〈 0.01 ）. Increasing the disk thickness resulted in decrease of △E values （P 〈 0.01 ） and increase of contrast ratio values （P 〈 0.01 ）. The thickness of IPS Empress glass-ceramic exhibits significant influence on the color masking ability, which should be considered when an IPS Empress glass- ceramic restoration is selected in clinical practice.