双侧上颌骨缺损颧种植体修复的有限元分析

目的:研究颧种植体结合血管化腓骨瓣修复双侧上颌骨缺损的生物力学分布情况,为临床上颌骨缺损功能性修复提供理论参考.方法:基于患者的CT扫描数据、图像及图形处理技术,模拟上颌骨双侧骨缺损状态.依照临床上颌骨缺损后修复设计方法,应用腓骨瓣、颧种植体结合常规种植体植入,利用三维有限元法分析该设计的生物力学情况.结果:颧种植体结合血管化腓骨瓣修复双侧上颌骨缺损模型的应力分布中,应力最大值分别出现在颧种植体穿过腓骨和颧骨的部位.种植体结构中弯曲变化的位移不明显,并且种植体整体位移在颧骨附近逐渐减小为零.结论:实验表明(牙合)力引起的应力主要由颧骨和腓骨所承担,颧种植体结合血管化腓骨瓣修复双侧上颌骨缺损能够合理分散并传导(牙合)力,其周围支持组织具有良好的应力分布.该方法恢复了双侧颧突支柱的功能,是一种双侧上颌骨缺损功能性重建的有效方法.

Finite element analysis of zygomatic implants in bilateral restoration of maxillary defect

PURPOSE：To evaluate the distribution of biomechanical stress on the craniofacial skeleton for bilateral maxillectomy reconstruction by using the vascularized fibula graft and zygoma implants,in order to provide theoretical references for restoration of maxillary defects.METHODS：Based on digital imaging and communications in medicine（DICOM） data and the image process technology,a modularized geometrical and finite element model of the human skull was built to simulate the bilateral defect pattern of the maxilla.Biomechanical properties of the zygomatic implants and the connected implants were evaluated by using finite element analysis（FEA） method.RESULTS：The deformation tendency of the zygomatic implants was identical and the displacement of bending was not noticeable.The displacement of the zygoma fixture near the zygoma was close to zero.The neck of the zygoma fixture on the fibula bone and on the zygoma bored the largest stress,while the rest of the peri-implant bones bored a lower stress.CONCLUSIONS：Stress from occlusal forces is mainly supported by the zygomatic bone and the fibular bone.The occlusal force is effectively transmitted and the stress distribution of the peri-implant bone of such reconstruction protocol is reliable.Reconstitution of the buttresses system ensures a stable support for occlusion and stress.This is a safe and effective method to optimize bilateral maxilla rehabilitation.