酸碱环境下循环载荷对氧化锆/饰面瓷叠层瓷抗弯强度的影响

The influence of dynamic cyclic loading on the bi-axial flexural strength of veneering porcelain for zirconia under different pH environment

目的:比较酸碱唾液浸泡环境下动态循环加载对氧化锆/饰面瓷叠层瓷抗弯强度的影响。方法:制作氧化锆/饰面瓷叠层瓷圆片试件45个,随机分为酸性、碱性及中性浸泡三组,循环加载10000次后进行双轴弯曲测试。用二参数Weibull分析法对数据进行分析。结果:中性环境下的弯曲强度值最大,碱性环境下的弯曲强度值最小。pH=7组的平均抗弯强度比pH=4组高14%左右,而比pH=8组高45%左右。本实验测得到的Weibull模量值分别是pH=7组15.5,pH=4组15.3,pH=8组8.9。R2值分别是pH=7组0.98,pH=4组0.97,pH=8组0.94。结论:牙科氧化锆全瓷修复材料使用后出现性能下降的疲劳现象,与牙科陶瓷修复体处于不同酸碱度唾液环境有关。

Objective： To determine the influence of cyclic loading test under different storage mediums condition on the bi-axial flexural strength of veneering porcelain for zirconia. Methods： Standardized disc specimens （16mm× 1.6mm） were pre-loaded 10,000 cycles, stored in pH7, pH 4 and pH 8 environment separately and then biaxial flexural strength was tested. The Weibull statistical approach was also utilized in order to describe the reliability of the failure strength data. Results： Discs showed the highest flexural strength in pH 7 and the lowest in pH 8. The flexural strength of the discs in pH 7 was approximately 14% higher than that in pH 4 and 45% higher than that in pH 8. Weibull modulus under pH=7, pH=4, pH=8 were 15.5, 15.3, 8.9, respectively. R2 values under pH=7, pH-4, pH=8 were 0.98, 0.97, 0.94, respectively. Conclusion： The result in this study was help to guide the clinical application of all-ceramics dental crown, which was suffered from bi-axial flexural strength at different storage mediums.