两种附着体义齿支持组织的应力比较分析

Comparative Study of Stress Distribution on the Supporting Tissue of 2 Attachment Dentures

目的比较球帽附着体和栓道式附着体义齿支持组织的Von Mises等效应力分布。方法分别建立基牙牙周组织正常、吸收1/4、吸收1/3、吸收1/2的两种附着体义齿的三维有限元模型,采用垂直向加载力300N,模拟单侧后牙咬合状态,分析支持组织的Von Mises等效应力。结果基牙牙周组织不同状况下,栓道式附着体义齿的基牙和牙周膜最大Von Mises等效应力值小于球帽附着体义齿,缺牙区牙槽嵴最大Von Mises等效应力值大于球帽附着体义齿,但其分布相对较均匀。结论基牙不同牙周状况下,栓道式附着体义齿与球帽附着体义齿相比,其支持组织应力分布相对较均匀,应力集中范围小,可见栓道式附着体舌侧对抗臂的设计可以使支持组织受力更均匀,更有利于基牙健康。

Objective To compare Von Mises equivalent stress distribution on the supporting tissue between ball-cap attachment denture and key-key way attachment denture. Methods The 3-dimensional finite element models of 2 attachment dentures with periodontal tissue normal, 1/4 absorbed, 1/3 absorbed and 1/2 absorbed, respectively; a vertical loading force of 300N was given and unilateral posterior occlusion was simulated; Von Mises equivalent stress distribution on the supporting tissue was analyzed Results Under different conditions of periodontal tissues, the maximum Von Mises equivalent stress values of abutment teeth and periodontal ligament of key-key way attachment dentures were smaller than those of ball-cap attachment dentures while the maximum Von Mises equivalent stress value of the alveolar ridge were greater than that of ball-cap attachment denture with a mean stress distributions. Conclusions The stress on the supporting tissue of key-key way attachment denture is more evenly distributed within a smaller range than that of ball-cap attachment denture and it is more fit for the health of abutment teeth.