微波烧结与常规烧结对牙科用氧化锆摩擦磨损性能的影响

目的 采用微波烧结与常规烧结牙科用氧化锆与滑石瓷进行摩擦磨损实验,探讨其摩擦磨损性能及对磨物的磨耗程度。方法 选取Lava品牌氧化锆试件10个,随机分为微波烧结组和常规烧结组。使用粗糙度轮廓仪测量氧化锆表面粗糙度;以滑石瓷球为对磨物进行磨损实验,记录摩擦系数曲线,计算磨损体积;采用光学显微镜观察氧化锆和滑石瓷球的磨损形貌,场发射扫描电子显微镜（SEM）观察氧化锆显微结构。结果 微波烧结和常规烧结氧化锆磨损量依次为（6.940±1.382）×10^-2、（7.952±1.815）×10^-2 mm³,对磨滑石瓷磨损体积依次为（14.189±4.745）×10^-2、（15.813±3.481）×10^﹣2 mm³,两种烧结方式氧化锆耐磨性及造成对磨物磨损量差异均无统计学意义。光学电镜显示氧化锆可见明显的犁沟;对磨滑石瓷可见裂纹,同时伴有犁沟。SEM显示两种烧结方式氧化锆均已致密烧结,微波烧结氧化锆晶粒更加细小均匀。结论 两种烧结方式氧化锆摩擦磨损性能接近。

Study on friction and wear properties of dental zirconia ceramics processed by microwave and conventional sintering methods

Objective This study evaluated the wear of an antagonist and friction and wear properties of dental zirconia ceramic that was subjected to microwave and conventional sintering methods.Methods Ten specimens were fabricated from Lava brand zirconia and randomly assigned to microwave and conventional sintering groups. A profile tester for surface rough-ness was used to measure roughness of the specimens. Wear test was performed, and steatite ceramic was used as antagonist. Friction coefficient curves were recorded, and wear volume were calculated. Finally, optical microscope was used to observe the surface morphology of zirconia and steatite ceramics. Field emission scanning electron microscopy was used to observe the microstructure of zirconia.Results Wear volumes of microwave and conventionally sintered zirconia were (6.940±1.382)× 10-2, (7.952±1.815) ×10-2 mm3, respectively. Moreover, wear volumes of antagonist after sintering by the considered methods were (14.189±4.745)×10-2, (15.813±3.481)×10-2 mm3, correspondingly. Statistically significant difference was not observed in the wear resistance of zirconia and wear volume ofsteatite ceramic upon exposure to two kinds of sintering methods. Optical microscopy showed that ploughed surfaces were apparent in zirconia. The wear surface of steatite ceramic against had craze, accompanied by plough. Scanning electron microscopy showed that zirconia was sintered compactly when subjected to both conventional sintering and microwave methods, whereas grains of zirconia sintered by microwave alone were smaller and more uniform.Conclusion Two kinds of sintering methods are successfully used to produce dental zirconia ceramics with similar friction and wear properties.