高周次动态载荷对牙科氧化锆陶瓷弯曲强度及可靠性影响  

The effect of high cycle dynamic loading on the bending strength and its reliability of dental zirconia ceramics

作　　者：陆英 龚旭 王似鋆 LU Ying;GONG Xu;WANG Siyun(Department of Stomatology,Affiliated Hospital of Shaoxing University,Shaoxing Municipal Hospital,Shaoxing 312000,China;State Key Laboratory of Military Stomatology&National Clinical Research Center for Oral Diseases,Department of Dental Materials,School of Stomatology,the Fourth Military Medical University,Xi’an 710032,China)

机构地区：[1]绍兴文理学院附属医院绍兴市立医院口腔科,浙江绍兴312000 [2]军事口腔医学国家重点实验室口腔疾病国家临床医学研究中心第四军医大学口腔医院口腔材料学教研室,陕西西安710032

出　　处：《温州医科大学学报》2022年第11期909-913,共5页Journal of Wenzhou Medical University

基　　金：浙江省教育厅一般科研项目(Y202147102)。

摘　　要：目的:探讨高周次动态加载对牙科氧化锆陶瓷弯曲强度及其可靠性的影响。方法:将30个制备好的牙科氧化锆陶瓷试件随机分成两组(n=15)。对照组不做处理,实验组试件进行300万次动态循环加载。测试对照组和实验组疲劳后试件的三点弯曲强度,并对结果进行Weibull分析和统计学分析。在对照组和实验组断裂的试件中各随机选取两个试件,在扫描电镜下观察试件断面的微观形貌,并做断口形貌学分析。结果:对照组和实验组的弯曲强度分别为(1 051.3±98.8)MPa和(890.2±128.2)MPa,差异有统计学意义(P<0.05);弯曲强度的Weibull模数分别为12.29和7.77,特征强度分别为1 095.4 MPa和946.5 MPa;实验组试件的断口中呈现大量闭孔,证实实验组试件内部出现了裂纹扩展。结论:高周次的动态循环加载能够在牙科氧化锆陶瓷内部产生疲劳裂纹,使其弯曲强度和可靠性降低,折裂风险升高。Objective:To investigate the effect of high cycle dynamic loading on the bending strength and its reliability of dental zirconia ceramics.Methods:A total of 30 dental zirconia ceramic specimens were randomly divided into 2 groups(n=15),with the experimental group subjected to dynamic cyclic loading for 3million times and the control group not treated.The three-point bending strength of all the samples was tested and the results were studied by Weibull and statistical analysis.The fractured surface morphology of 2 specimens randomly selected from each group was observed under the scanning electron microscope.Results:The bending strength of the control and the experimental group was(1 051.3±98.8) MPa and(890.2±128.2) MPa respectively(P<0.05),with the control group was significantly higher than the experimental group.The Weibull modulus of bending strength was 12.29 and 7.77 respectively,and the characteristic strength was 1 095.4 MPa and 946.5 MPa respectively.A large number of closed holes were found in the fracture surface of the experimental group,which confirmed the crack propagation in the specimens.Conclusion:Fatigue cracks can be produced by high cyclic dynamic loads in dental zirconia ceramics,which reduces the bending strength and reliability while increases their fracture risk.

关 键 词：牙科氧化锆陶瓷 高周动态加载 弯曲强度 可靠性 

分 类 号：R783.1[医药卫生—口腔医学]