单端固定式下颌骨修复体的应力分析

目的：针对包括一侧髁状突的下颌骨缺损,通过有限元应力分析,了解单端固定式下颌骨修复体在功能运动时的受力与变形规律,以期寻求更加合理的修复体的设计和固定方式。方法：建立下颌骨断端和修复体的简易三维模型,模拟咀嚼运动,施加垂直方向载荷,进行有限元法应力分析,计算出该模型各组成部分的应力分布和受力变形。结果：在该模型加载时,延伸板基部和近断端处上部的螺钉颈部是应力集中的部位,近断端处下部的螺钉颈部和修复体的远端舌侧为形变最大的部位。结论：单端固定式下颌骨修复体在加载时,延伸板的基部和靠近断端的固定螺钉是应力集中的部位,修复体远离固定的一侧是变形最大的部位,提示我们应将延伸板形态设计为尽可能加宽,并应增加下颌骨下缘处的固定,使修复体与下颌骨断端受力更加合理,变形也尽可能缩小。

Stress Analysis of Single-ended Fixed Mandibular Prosthesis

Objective：To analyze the stress and strain on titanium framework,end of mandible and fixing screws in load when the defect area includes unilateral condyle.Methods：Firstly establish 3D finite element model of defective mandible and titanium frameworks,and then vertical load were exerted on them to simulate the mastication movement.Finally,stress and strain situation of the model were analyzed.Results：When the model was loaded,the stress concentrated at base of extending plate and neck of the screw upper near bone end.Neck of the screw lower near bone end and lingual part farther from bone end deformed most severely.Conclusion：In design of titanium framework fixed unilaterally to repair the mandible bone defects including a condyle,the extend plate should be widen and overcoat the inferior border of it,moreover,stronger fixation in inferior border of mandible is necessary.