下颌后牙固定桥支持骨组织应力的三维有限元法分析——Ⅰ.固定桥基牙周围牙槽骨的表面应力分析

Three dimensional Finite Element Analysis of Stress\;in Supporting Bone of Mandibular Posterior Fixed Bridge\;Ⅰ. Stress Analysis of the Surface\;of Alveolar Bone Around Bridge Abutments

目的:研究下颌后牙固定桥基牙周围牙槽骨表面的应力状态。方法:以成人下颌骨为解剖学基础,建立固定桥及其基牙支持组织的三维有限元模型。分别在6种垂直向载荷和1种水平向载荷条件下,计算出基牙周围牙槽骨表面的最大主应力(εmax)、最小主应力(εmin)值。结果:垂直向载荷下,应力集中在根尖和颈部牙槽骨,颈部主要为拉应力,根尖区均为压应力;双尖牙周围牙槽骨应力最大值约为磨牙的2.1倍;水平向载荷下应力明显增加,约为垂直向载荷的3.5倍,且应力分布规律有明显的改变。结论:本实验结果为固定桥的设计提供了参考依据。

Objective:Stress levels of the surface of alveolar bone around bridge abutment of posterior fixed bridge were studied. Methods:The three dimensional finite element model was developed on the basis of a try adult mandible. 6 vertical and 1 horizontal loadings were applied respectively, and the Maximum stress(ε\-\{max\}) and the Minimum stress(ε\-\{min\}) of the surface of alveolar bone around bridge abutment were calculated. Results:The stress concentration exhibited at the apical and cervical regions. The stress of the bicuspid was about 2.1 times as high as that of the molar. When transverse loading was applied, the stress level was about 3.5 times as high as that when vertical loading was applied. Conclusion:The results were greatly valuable to design of posterior fixed bridge.\;