不同载荷下天然牙一种植牙联合桥基牙应力分布

目的：揭示天然牙一种植体联合支持固定桥在不同载荷下基牙的应力反应规律，指导临床优化设计。方法：采用三维有限元方法建模计算、分析。结果：斜向载荷下种植体的最大应力值是天然牙的2－2．5倍，集中斜向载荷与分散斜向载荷下种植体最大应力值无明显差异，是垂载荷下种植最大应力值2－2．5倍。集中垂直载荷下天然牙、种植体的最大应力值高于分散垂直载荷下的最大应力值，天然牙集中斜向载荷下最大应力值大于分散斜向载荷下的最大应力值。结论：天然牙一种植体联桥受侧向力的能力弱，种植体应具有高强度，天然牙根应粗大，减小侧向力，集中载荷比分散载荷破坏作用大，桥体与基牙的He面咬合接触点分布均匀，建立多点咬合接触。

Stress Distribution onAbutment of Tooth- Implant Fixed Bridge Under Different Loading

To discovery the stress distribution on the abutments of tooth - implant fixed bridge under differ ent loading.Method: By 3- D finite element modeling computed and analyzed .Results: Under oblique loading, stress on the implant was 2 ～ 2.5 times as big as on tooth. There was no significant deviation of the biggest stress on the implant between concentrated oblique loading and oblique dispered loading. The biggest stress on implant under concentrated oblique loading was 2 ～ 2.5 times as big as vertical laoding. Both tooth and implant, the stress under concentrated vertical loading was bigger than under dispersed vertical loading. On the tooth, stress under concentrated oblique loading was bigger than under dispersed oblique loading. Conclusion:The ability of supporting oblique force for tooth- implant fixed bridge is weak. Implant should be of higher strength, tooth root should be stronger, oblique force should be less. Distruction of condentrated loading for abutment is more serious than dispersed loading. The bite points should be well distributed.