种植全口义齿的三维有限元分析——基托内金属支架对应力的影响

A 3dimentional finite element analysis(3D FEA) of the complete dentures supported by implants with or without metal frame in base

目的：研究基托内金属支架放置与否对种植全口义齿及其支持组织应力状况的影响。方法：用三维有限元方法，按义齿连接设计的不同，分析比较埋置与不埋置金属支架时种植全口义齿的应力状况。结果：不使用金属支架较使用金属支架，在种植全口固定义齿，骨界面应力增加２７％，基托应力增加３７％，种植体应力增加２１％；在种植全口覆盖义齿，骨界面应力减少１６％，而粘膜应力增加９％，基托应力增加１０％，种植体应力增加１９％。结论：种植全口固定义齿的基托内应使用金属支架以减少各部应力，而种植全口覆盖义齿可不使用金属支架以减小最有害的种植体骨界面应力。

Objective: To study the stress states of the dentures supported by implants with or without metal frame in base. Methods: 3D FEM was employed to investigate the stress of implantsupported complete dentures when metal fram was used in the denture base or not. Results: Without metal frame in the base, the stress level in the implantbone interface, the denture base and the implant increased by 27%, 37% and 21% respectively in the fixed dentures; the stress level in the implantbone interface, decreased by 16%, but that in mucosa, the base and the implant increased by 9%, 10% and 19% respectively in the overdenture. Conclusions: Metal frame should be used in the denture base in order to decrease the stress of all parts of the implantsupported fixed complete denture, but may not be used in order to decrease the stress of implantbone interface of the implantsupported overdenture.