【摘要】 目的 分析MC切削陶瓷的可切削性能。方法 测量MC氧化铝块和Vita In-Ceram Alumina Block的三点弯曲强度、断裂韧性和维氏硬度,计算陶瓷可加工指数,记录用两种瓷块在CerecⅡ型CAD/CAM机上加工下颌第一双尖牙底层冠所用时间。结果 MC氧化铝陶瓷的三点弯曲强度为(100.59±2.77)MPa,低于Vita In-Ceram Alumina Block的(112.47±9.37)MPa,两者间差别无统计学意义;MC陶瓷可加工指数为1.01,高于Vita In-Ceram Alumina Block的0.79;在CerecⅡ型CAD/CAM机上加工下颌第一双尖牙底层冠,两种瓷块的磨削时间都是(465±0)s。结论 MC氧化铝瓷块与进口的氧化铝陶瓷性能相当,可以满足牙科CAD/CAM加工的需要。更多还原

【Abstract】 Objective This study measured machinable properties of the MC alumina ceramic by comparing it with Vita In-Ceram Alumina Block. Methods Three-point bending strength, fracture toughness and surface toughness were measured, and then Milling index (M) was calculated. The copings of mandibular first premolar were made by MC machinable ceramic and Vita In-Ceram Alumina Block with Type Ⅱ Cerec CAD/CAM machine. Record the milling time. Results The bending strength of MC alumina ceramic was (100.59±2.77) MPa, which was lower than that of Vita (112.47±9.37) MPa, but the difference has no significance. Milling index of MC machinable ceramic was 1.01. This figure was higher than that of Vita In-Ceram Alumina Block (0.79). Milling time of both ceramics was (465±0) s. Conclusion The machinable properties of MC alumina ceramic corresponded with those of Vita alumina ceramic, and the material could meet the demand of CAD/CAM system in dentistry.更多还原