Vita Classical比色片颈、中、切部色度值的测定及分析

Test and analyses of chroma of Vita Classical shade guides in cervical,middle and incisal positions

目的 对比分析Vita Classical比色片颈部、中部、切部色度值,探讨同名比色片这3个部位颜色是否一致.方法 利用MINOLTA CR-321接触式色差计,以CIE-1976-L＊a＊b＊表色系统,分别测定5套Vita Classical比色片颈部、中部、切部1/3色度值,并进行组间色差对比分析.结果 各部位色差均在1.70～4.25之间;C4比色片的切部与中部ΔE＜1.7.16个Vita Classical比色片颈部与中部,切部与中部,颈部与切部之间的平均色差分别是4.38,2.13,5.19,ΔE＞1.7.结论 Vita Classical 16个比色片,在比色的过程中,不能只进行中部或局部的颜色比较.局部色不能反映该比色片完整颜色状况,各部位的颜色均存在差异.

Objective To investigate whether the color of Vita Classical shade guide in 3 different positions is consistent by comparing and analyzing the chroma of shade guide（Vim Classical） in cervical, middle and incisal positions. Methods The chroma of 5 sets of Vita Classical shade guide in cervical, middle and incisal positions was tested using MINOLTA CR-321 contacted colorimeter（D65 respectively） and the color was measured by CIE-1976-L ＊ a ＊ b ＊ system. The differences were contrasted and analyzed. Results The color differences in the three positions were between 1.70 and 4.25; the color differences between incisal and middle positions of C4 were smaller than 1.7; the mean color differences between cervical and middle positions, incisal and middle positions, cervical and incisal positions of 16 shade guides（Vita Classical） were 4.38, 2.13 and 5.19, respectively（△F. 〉 1.7）. Conclusions In the process of color matching, it is unfit to contrast the color only in the middle of the tooth. The color of middle part cannot represent the whole color of the shade guide.