The effect of high cycle dynamic loading on the bending strength and its reliability of dental zirconia ceramics
LU Ying1, GONG Xu2, WANG Siyun1
1.Department of Stomatology, Affiliated Hospital of Shaoxing University, Shaoxing Municipal Hospital, Shaoxing 312000, China; 2.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
LU Ying,GONG Xu,WANG Siyun. The effect of high cycle dynamic loading on the bending strength and its reliability of dental zirconia ceramics[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2022, 52(11): 909-913.
Abstract：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 3 million 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.
