Clinical Evaluation of Color Matching System for Ceramic by Field Test

本研究的目的是对我科开发的基于计算机配色（Computer color Matching, 0CM）的陶瓷修复色彩再现系统进行临床评价。为了对该系统进行评价，在三家牙科机构中对多光谱相机测色系统的效率和颜色再现精度进行了分析。采用COM配方制作金属陶瓷冠，再现上前镜目标自然牙的颜色，并与目标自然牙的颜色进行了对比分析。提出了以下需要改进的地方。(1)测色仪的小型化；(2)缩短测色时间；(3)多光谱图像的彩色显示；(4)测色与CCM计算的连接；(5)陶瓷粉末自动称重仪的研制。切牙区颜色再现精度较颈椎区和中央区差。特别是在低透明度和强烈着色的切牙区域，CCM计算的预测结果和CCM冠的颜色都不理想。认为目前系统中釉质陶瓷的三种色度构成的颜色空间不足以覆盖天然切牙的颜色空间。综上所述，牙釉质陶瓷的色度和数量以及牙切面积CCM的计算方法需要重新考虑。牙冠的颜色是影响口腔美容的重要因素。我们将努力建立具有下个世纪牙科智能网络的CCM系统。

The purpose of this study is to evaluate clinically the color reproduction system for ceramic restoration based on Computer Color Matching (0CM) which was developed in our department. In order to evaluate this system, the efficiency of color measuring system with Multi-spectrumm Camera and the precision of color reproducibility were analyzed in three dental institutioa Metal ceramic crowns were fabricated according to COM formulation to reproduce the color of target natural tooth for upper anterior mcisor, and the color of crowns were analyzed compared to target natural tooth. The following needs of improvement were suggested. (1)Miniaturization of the color measuring instrument, (2)Shortening of the color measuring time, (3)Color display for Multi-spectrum images, (4)Connection of color measurement and CCM calculation, (5)Developrnent of automatic weight measuring instrument for ceramic powder.The precision of color reproduction for incisal area was inferior compared to cervical and central area. Especially in case of low translucency and strong colored incisal area, the predicted result of CCM calculation and the color of CCM crowns was not adequate. It was suggested that the color space constructed by three shades of enamel ceramic in present system could not cover enough the color space for natural incisal tooth. In conclusion, shade and number for enamel ceramic and the method of CCM calculation for Incisal area should be reconsidered. The color of crown is very important factor for the esthetic dentistry. We will try to establish the CCM system with an intelligence net work in dentistry for next century.