下颌第一磨牙全瓷冠疲劳寿命预测的三维有限元分析

Lifetime Prediction of All-ceramic Crowns of the Mandibular First Molar:A three-dimensional Finite Element Analysis

目的：对EmpressⅠ、EmpressⅡ、In—Ceram Alumina以及In—Ceram Zirconia 4种不同材料的下颌第一磨牙全瓷冠进行疲劳寿命预测。方法：模拟1、5、10年间，相当于最大咬合力的循环疲劳载荷，加载于全瓷冠模型。通过有限元疲劳分析软件MSC．Fatigue预测各种材料全瓷冠的失效概率。结果：基于本有限元疲劳分析，EmpressⅠ、EmpressⅡ、In—Ceram Alumina以及In—Ceram Zirconia这4种均可应用于后牙全瓷冠。其中采用EmpressⅠ制作的全瓷冠较其他3种材料具有较高的失效概率（3．15％～7．486％）。结论：有限元疲劳分析有助于全瓷修复材料临床应用前的耐疲劳强度的判断。

Objective： To predict the fatigue lifetime of all ceramic crowns （ EmpressⅠ , Empress Ⅱ , In - Ceram Alumina and In- Ceram Zirconia）of the mandibular first molar. Methods： A cyclic fatigue loading, simulating the maximum bite force was applied vertically to the crowns. The failure probability of different crown models were predicted by means of the MSC. Fatigue. , the finite element fatigue analysis software. Results： EmpressⅠ ,Empress Ⅱ ,In - Ceram Alumina and In - Ceram Zirconia seem to be sufficient as posterior all - ceramic crowns materials based on this prediction. Crowns made of EmpressⅠ showed a relative high failure probability （3.15% ～ 7. 486% ）. Conclusions： The finite element fatigue analysis method can help to judge the ceramic materials with respect to fatigue strength before clinical use.