种植体上部不同结构对下颌游离端义齿应力分布的影响

摘要

Objective: To study the influence of different structures upon implants of tooth-implant-removable partial denture support on the stress distribution in periodental tissues and on the displacement at different location. Methods: 4 three-dimensional finite element models of implant-tooth-supporting Kennedy Class I removable partial denture were created. Effects of different structures upon implants (ITI Straumann?and NOBEL Replace?Tapered) were evaluated under vertical loading. The variation of displacement of peri-odontium under saddle and the stress in the bone around implants, in periodonlal membrane of abutments and in residual ridge were analysed. Results; The lowest values of stress and displacement for all the structures was found when micro-ERA attachment was used. Conclusion; Micro-ERA attachment may be the appropriate choice for tooth-implant supported removable partial denture.%目的:观察不同上部结构的种植体支持可摘局部义齿修复下颌Kennedy Ⅰ类牙列缺损时的应力和位移.方法:使用软件GeoStar( COSMOSM 2.85,SRAC,USA)建立4个种植体-天然牙联合可摘义齿修复下颌Kennedy Ⅰ类牙列缺损的三维有限元模型,比较不同上部结构时种植体周围骨组织、基牙牙周膜、基托下黏膜的最大等效应力及基托下黏膜组织的位移变化.结果:有种植体支持时,单冠形式的种植体周围骨组织最大等效应力最大；缓冲型套筒冠的基牙牙周膜最大等效应力、基托下黏膜最大等效应力和位移值最大；微型太极扣种植体周围骨组织最大等效应力、基牙牙周膜最大等效应力和黏膜的最大等效应力及位移值均最小.缓冲型套筒冠种植体周围骨组织最大等效应力小于非缓冲型套筒冠,但基牙牙周膜最大等效应力、基托下黏膜最大等效应力和位移则大于非缓冲型.结论:选用种植体-天然牙联合支持修复远中游离端牙列缺损时,种植体上部结构采用微型太极扣作为附着体联接形式是最佳选择.