唇侧植骨不同种植修复体的三维有限元分析

Three-Dimensional Finite Element Analysis on Different Implant Prostheses for Labial Bone Graft

目的分析植骨和修复体对种植修复体内部结构及周围骨组织应力分布的影响。方法建立由两种唇侧骨质牙槽骨模型支持且分别为钴铬合金烤瓷冠与二氧化锆全瓷冠修复的上颌中切牙种植修复体模型,对其进行力学加载,分析植骨与修复体对植体内部各结构与植体-骨界面应力分布的影响。结果植骨组中固位螺丝唇侧体部处及种植体唇侧骨组织中应力远低于非植骨组,但植骨组种植体颈部处的应力则高于非植骨组。相同骨质条件下,二氧化锆全瓷冠组在固位螺丝唇侧体部处的应力大于钴铬合金烤瓷冠组。结论修复体对种植修复体内部结构及周围骨组织应力分布的影响不大,但植骨影响的唇侧骨质差异可影响固位螺丝体部及植体-骨界面处的应力集中状况。

Objective To analyze the influence of bone graft and prosthesis on stress distributions in internal structure and surrounding bone tissues of implant prosthesis. Methods Two models of maxillary central incisor implants supported by two kinds of labial alveolar bone models were established,which were restored by porcelain fused metal (PFM) crown and zirconia all-ceramic crown,respectively. The mechanical loads were applied to analyze the influence of bone graft and two different prostheses on stress distributions of internal structure of the implant and interface between the implant and bone. Results In bone graft group,the stress in labial part of the retaining screw and labial bone tissues of the implant was much lower than that in non-bone graft group,but the stress of the implant neck was higher in bone graft group than that in non-bone graft group. Under the same bone condition,the stress of zirconia all-ceramic crown group on lip side of the retaining screw was greater than that of PFM crown group. Conclusions Prosthesis have little effect on stress distributions of internal structure and surrounding bone tissues of implant prosthesis,but the difference of labial bone affected by bone grafts can affect stress concentrations of the retaining screw and the implant-bone interface.