计算机辅助设计与计算机辅助制作后牙修复体的三年临床观察及失败病例分析

目的评估计算机辅助设计（computer aided design，CAD）与计算机辅助制作（conaputer aided manufacture，CAM）后牙全瓷修复体的3年临床使用效果，分析病例失败的原因。方法使用CAD—CAM系统和可切削瓷块治疗32例后牙大面积牙体缺损患者，共修复14颗前磨牙和18颗磨牙。根据缺损的形态和体积分别制作11个嵌体、10个冠和11个髓腔固位冠，追踪观察3年。结果28个修复体完好，2个修复体折断（磨牙嵌体和冠各1个）并重新制作，2个修复体边缘破损（磨牙和前磨牙嵌体各1个）。结论在正确选择适应证并严格按要求进行牙体预备的前提下，使用CAD．CAM全瓷修复能满足患者对咀嚼功能和美学的要求。

Three-year clinical observation and failure analysis of all-ceramic restorations made by chair-side computer aided design and computer aided manufacture system

OBJECTIVE: To evaluate 3-year clinical performance of restorations made by chair-side computer aided design and computer aided manufacture (CAD/CAM) system and analyze possible failure reasons. METHODS: Thirty-two single-tooth large all-ceramic restorations were fabricated using a computer aided design and computer aided manufacture (CAD/CAM) system. Fourteen premolars and 18 molars were restored with machined porcelain blocks. Of these 11 inlays, 10 crowns, and 11 endocrowns were finished respectively. The integrity and marginal fitness were evaluated at 3 years after insertion. RESULTS: Twenty-eight restorations were rated as good; 2 were fractured (1 molar-crown and 1 molar-inlay) and had to be replaced; and 2 were found marginal defects (1 molar-inlay and 1 premolar-inlay). The failures occurred mostly in the inlays and molars. CONCLUSIONS: With proper indication selection and careful tooth preparation, restorations with chair-side CAD/CAM were clinical success both in function and esthetics.