牙科CAD/CAM加工用氧化铝块的研制与性能测试

Development of partially sintered alumina block for dental CAD/CAM and mechanical properties testing

目的 探讨用预成氧化铝块经牙科CAD/CAM(computeraideddisign/computeraidedmanufacturing,计算机辅助设计/计算机辅助制造)加工和玻璃渗透技术结合,制作牙科高强度全瓷修复体的新途径。方法 用高纯度、精细氧化铝经等静压成型,低温烧结制作部分烧结的氧化铝块,测试了其力学性能并用扫描电镜分析其显微结构。结果 部分烧结氧化铝块的显微硬度、3点弯曲强度、断裂韧性分别为165MPa、210MPa、192MPam1/2。扫描电镜显示颗粒间的表面扩散和颈部生长使部分烧结体保持一个三维连续的开孔结构。结论 部分烧结氧化铝块可满足牙科CAD/CAM加工和制作全瓷冠的需要。

Objective It is a new way to fabricate all ceramic crowns by combining dental CAD/CAM with glass infiltration technology Methods A partially alumina sintered block made of a high purity, fine alumina powder was shaped by isostastic pressure and sintered at 1 400℃ Its mechanical properties were tested and microstructure was observed by SEM Results The Vicker's hardness, three point bending strength, fracture toughness of partially sintered alumina block were 1 65MPa, 210MPa, 1 90MPam 1/2 respectively Micrographs of SEM indicated that partially sintered alumina contained the structure of continuous three dimensional open pores through the neck growth and surface diffusion of the interparticles Conclusion The partially sintered alumina block that developed in this way may be used to mill for CAD/CAM and fabricate the shrinkage free all ceramic crown