个体化下颌修复体三维有限元模型的建立及优化设计研究

An investigation on establishment and optimal design of three-dimensional finite element model for individualized reconstruction of mandibular prosthetic replacement

目的对采用现行设计方案下设计出的个体化下颌修复体修复后的下颌骨双侧髁突进行生物力学分析,根据应力分布情况,提出初步的个体化下颌修复体的结构优化设计方案,为以后下颌骨缺损的个体化功能性修复奠定一定的基础。方法建立正常下颌骨的三维有限元模型,利用CAD软件模拟下颌骨的部分缺损,并设计两种不同厚度的个体化修复体加以修复,然后进行三维有限元建模和应力分析。结果成功建立了两种工况下的下颌骨三维有限元模型。力学分析结果显示:应力在两种工况下都能通过修复体有效的传导,但常规工况条件下,双侧髁突应力分布在前斜面呈现明显不对称性。而在对照工况条件下,两侧髁突应力大小与分布较一致对称。结论建立的修复体修复的下颌骨三维有限元模型及力学分析结果可以为以后修复体的结构优化设计提供借鉴和参考。

Objective To carry out biomechanical analysis on bilateral mandibular condylar process after individualized reconstruction of mandibular prosthetic replacement designed by using current design program,further propose preliminary design program for structural optimization of individualized reconstruction of mandibular prosthetic replacement according to stress distribution,and establish certain basis for individualized functional repairing of mandibular defect in the future.Methods Three-dimensional finite element model for normal mandible was established and CAD software was used to mimic partial mandibular defect,and two kinds of individualized mandibular prosthetic replacements with different thickness were designed for repairing,then three-dimensional finite element model was established and stress analysis was carried out.Results The three-dimensional finite element model for mandible under two operating conditions was successfully established.The results from mechanical analysis showed that the stress forces can be effectively conducted under the two operating conditions,but the stress distribution of bilateral mandibular condylar process showed obvious asymmetry at anterior slope underthe routine operating condition,while stress intensity and distribution of bilateral mandibular condylar process at the control operating condition should be coincident and symmetric.Conclusion The established three-dimensional finite element model for individualized reconstruction of mandibular prosthetic replacement and the results from mechanical analysis can provide references for the design for structural optimization of prosthetic replacement in the future.