天然牙一种植体联合支持固定桥对种植体周骨组织应力的影响

目的 不同桥体长度结构下天然牙－牙种植体联合支持固定桥中种植体周骨组织的应力反应特点。方法 采用三维有限元方法建立不同桥长的固定桥力学模型计算分析。结果 天然牙－牙种植体联合支持固定桥中种植体颈部周围骨应力最大；长桥体固定桥在集中斜向载荷作用下种植体颈缘骨最大应力是集中垂直载荷下种植体周骨最大就力的3倍，桥体长度增加，应力值增加。结论 桥体长度对种植修复体应力分布有显著影响，桥体长度增加导致牙种植体及其周围骨应力集中程度增大，对其破坏作用增强，因此临床设计桥体不宜过长。

The action of different pontic length to the fixture supporting bone of natural tooth-fixture fixed bridge

Objective To study the stress distribution of the fixture supporting bone of different pontic length of fixed bridge supported by tooth and fixtune.Methods By the 3-dimensional finite element,the biomechanical Models of the fixed bridge Supported by tooth-fixture with 3-kind of pontic length were estiblised,calculated,analysised.ResultsThe biggest stress were at the bone around the fixture neck area;The biggest stress under the concentrated oblique loading was 3-times than that under the concentrated vertical loading;The larger of the pontic length was the bigger of the stress.Conclusion The concentrated oblique loading shuld be reduced when tooth-fixrture supported fixed bridge is desiged;The neck area bone of fixture shuld be of enough amount and density to resist obilique force;the length of pontic of tooth-fixture supported fixed bridge should not be too long.