种植全口义齿的三维有限元分析——上部连接设计对应力的影响

A 3dimentional finite element analysis (3D FEA) of the complete dentures supported by implants with varied connecting structures

目的：分析选用不同上部连接设计时种植全口义齿及其支持组织的应力状况以指导临床设计。方法：用三维有限元法研究螺丝固定结构与球帽附着结构对种植体全口义齿应力状况的影响。结果：采用螺丝固定结构较采用球帽附着结构者，义齿的种植体骨界面应力高出６１％，基托应力高出２１８％，种植体本身应力及人造牙列应力变化不大。结论：球帽附着结构较螺丝固定结构能显著降低种植体骨界面应力和义齿基托应力，利于义齿坚固耐用和支持组织健康。

Objective: To study the stress states of the complete dentures supported by implants with varied connecting structures in order to guide the design in clinic. Methods: 3D FEM was used to investigate the stress in the dentures attached to implants by ballcap structures or by screws. Results: The maximum stress in the implantbone interface resulted from the dentures attached to implants by screws was 61% higher than that by ballcap structures, the maximum stress in the denture base in the former was 218% higher than that in the later. However, the stress levels in the implants and artificial teeth showed no difference between the two kinds of dentures. Conclusions: The ballcap attachment can remarkably decrease the stress level in the implantbone interface and denture base, and is better to the sturdy of the dentures and the health of supporting tissues than screw attachment.