评价不同瓷贴面修复材料制作修复体颜色的匹配性

背景：瓷层材料厚度是贴面修复体颜色再现的关键因素。由于瓷贴面瓷层构建空间有限，难以对基牙颜色有明显的遮盖作用，最终修复后的颜色效果是由修复体的颜色和基牙颜色叠加而来的，近年对计算机辅助设计（computer aided design，CAD）制作的贴面材料对颜色的影响研究较少。目的：评价不同瓷贴面修复材料制作的修复体的颜色与比色板色标的颜色匹配性。方法：应用3种瓷贴面材料（维他Mark II，义获嘉E.max CAD LT，义获嘉Empress CAD Multi，均为A2色调）制作瓷贴面修复体共15个。每个贴面厚度为0.6 mm。用自然代型树脂材料制作贴面的基底，将实验试件放在暗盒合中，用奥林巴斯Crystaleye比色仪分别对贴面修复体颜色进行比色。选取修复体颈部、中部和切端与VITA标准比色板A2色标比较颜色的差别，对色差值进行单因素方差分析。结果与结论：E.max CAD LT瓷块在3种瓷块中最接近于标准比色板的颜色。单因素方差分析表明，瓷贴面修复体颈部颜色与色标颜色的差别在不同的修复材料间差异具有显著性意义（P 〈0.05），并且随着切、中、颈部位的不同而改变。在颈部颜色区域中，3组材料与色标的差异有显著性意义（P 〈0.05）；3组试件间的中部和切端的L值、切端的a值和颈部的b值均差异有显著性意义（P 〈0.05）。结果证实，不同全瓷材料制作的贴面修复体与比色板色标颜色存在差异，同时不同的CAD瓷块间也存在着颜色的差异。在临床应用中应注意修复体的最终颜色效果，借助表面染色技术和黏接时选择不同颜色的黏接剂进行修整。

Color matching of different porcelain veneer materials

BACKGROUND：The thickness of ceramic materials plays a crucial role in the reappearance of veneer restorations. Due to the limited space for the construction of porcelain veneer, it is difficult to cover the abutment tooth color, and the final color after restorations is achieved through the overlapping of prosthetic restorations color and abutment tooth color. In recent years, there is little evidence on the effect of veneer materials on the color. OBJECTIVE：To evaluate the color matching of porcelain veneer restorations with different ceramic materials to shade tab. METHODS：Fifteen veneer restorations were fabricated by three ceramic materials （VITA Mark II, Ivoclar E.max LTCAD and Ivoclar E.max CAD Multi, A2 shade）. Veneer restorations were controled at the thickness of 0.6 mm. The color parameters of veneer restorations were measured by Olympus Crystaleye against the natural color shade resin material substrate. The color differences were calculated between veneer restoration and shade tab （A2 shade） at the cervical, central and incisal sections, respectively. The color differences （？E values） were statisticaly analyzed using a one-way analysis of variance. RESULTS AND CONCLUSION：The color value of E.max CAD LT block was the closest one among the three blocks to the standard shade guide. The results of one-way analysis of variance for the ？E values showed that, there were significant differences between the cervical sections of the veneer restorations and the shade guide（P〈 0.05）. At the cervical sections, the ？E values between three kinds of blocks with the standard shade guide showed significant differences （P 〈 0.05）; the differences were also significant in L values at the central and incisal sections, a values at the incisal sections and b value at the shoulder sections （P 〈 0.05）. Our findings indicate that, there are significant differences in the color of porcelain veneer restorations with different ceramic materials to shade tab. The difference is also found