全下颌改良杆卡式和传统卡式种植覆盖义齿受载的比较性研究

A comparative study of stres distribution of modified and conventionsl bar - clip implant-borne overdenture in the edentulous mandible under static loads

目的：分析全下颌改良杆卡式种植覆盖义齿受载的应力分布并与传统的杆卡式比较。方法：三维各向异性有限元法。结果：种植体界面骨组织的最大应力出现在种植体颈部周围的骨皮质界面；种植体的最大应力主要位于种植体骨外段的近、远中面；牙弓后部牙槽嵴粘膜中有应力集中；改良式与传统式比较，种植体及其周围骨界面的应力峰值差别不大，但应力分布有一定差异，改良式者更均匀。而两种义齿牙弓后部牙槽嵴粘膜中的应力峰值及应力分布差别不大。结论：改良杆卡式种植覆盖义齿受载的应力分布比传统杆卡式者更均匀。

Objective: The authors analyze the stress distribution of the modified and conventional bar - clip implant - borne overdeture in the edentulous mandible under static loads. Methods: Three-dimensional anisotropic finite element method. Results The highest stress in bone around the implant was located at the neck of the implant in the upper conical layer, while the highest stress in implants found at upper and distal or mesial part of implants themselves. The stress concentration was also found in the membrana located in the posterior part of ridge. The stress distribution of modified bar - lip implant- borne overdenture seemed more uniform than that of conventional bar -clip implant-borne overdenture, however, the value of stress peaks in implants and in bone-implant interface looked similar. In addition, the stress pesks and stress distributin on the membrana located in the posterior part of ridge of modified bar - clip implant-borne overdenture differed from conventional bar-clip implant-borne overdenture. Conclusion: The stress distribution of modified bar We clip implant - borne overdenture seemed more uniform than that of conventional bar - clip implant - borne overdenture.