烧结次数对3种金属基底烤瓷冠颜色的影响

Influence of repeated firings on color of metal ceramic restoration

目的研究烧结次数对不同的金瓷修复体颜色的影响。方法利用同一副带有1活动代型的标准模型,分别制作A2色镍铬合金烤瓷冠、金合金烤瓷冠、金沉积烤瓷冠,每组各6件,反复烧结,应用CIE1976 L*a*b*颜色系统,采用高像素数码摄影及计算机处理技术,在标准光源及相同条件下,每次烧结后对其颜色进行测定。结果3种金瓷修复体随着烧结次数增加,明度、彩度均不断增大,烧结8次时明度最高,但继续烧结至10次后,明度逐渐下降;在色差上,3种金瓷修复体烧结6次时变色,金沉积烤瓷冠颜色稳定性优于其它两种。结论多次烧结对金瓷修复体颜色有一定的影响,技工制作金瓷修复体时烧结次数适宜控制在6次内;3种金瓷修复体颜色稳定性,金沉积烤瓷冠和金合金烤瓷冠优于镍铬合金烤瓷冠。

Objective To investigate the repeated firings on the color of metal ceramic restoration. Methods Three types of metal ceramic restorations were made on the basis of the same die. After enamel layer was spread, metal ceramic restorations were fired repeatedly. In the same condifion,CIE1976 L ＊ a ＊ b ＊ color system and a digital camera and computer and a standard light source were selected to measure and compare the characteristics of the three types of metal ceramic restorations after repeated firings. Results After repeated firing, light value and chorma value of three types of metal ceramic restoration increased. But after the tenth firing, light value was decreased. After the sixth firing,color changes were found in the three types of metal ceramic restorations. Auro-galvano-crown was better than the other crowns in the color stability. Conclusions There is some influence on the color of metal ceramic restoration after repeated firing. Firing times should be fewer than six times in the course of facture of metal ceramic restoration. Auro-galvano-crown is better than the other crowns in the color stability.