Clinical Evaluation of Color Matching System for Ceramic by Field Test

本研究的目的是对我科自行研制的基于计算机配色的烤瓷修复体颜色再现系统进行临床评价。为了对该系统进行评价，对三个口腔机构的多光谱测色系统的效率和颜色重现性的精确度进行了分析。根据COM公式制作金属烤瓷冠，以再现上前牙目标天然牙的颜色，并与目标天然牙的颜色进行对比分析。提出了以下改进的需要。(1)测色仪器的小型化，(2)测色时间的缩短，(3)多光谱图像的彩色显示，(4)测色与CCM计算的连接，(5)陶瓷粉自动测重仪的研制。特别是在半透明程度较低、切牙颜色较强的情况下，CCM计算的预测结果和CCM冠的颜色预测结果并不理想。提示目前三种色度的釉质陶瓷所构成的色彩空间不足以覆盖天然切牙的色彩空间。综上所述，釉质陶瓷的色泽和数量以及切面面积的CCM计算方法应重新考虑。牙冠颜色是影响牙科美容的重要因素。我们将努力在下个世纪建立具有智能网络的口腔医学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.