载荷下腭穹隆形态、牙尖斜度对上颌全口义齿基托应力分布的影响

目的:研究载荷下腭穹隆形态及牙尖斜度对上颌全口义齿基托应力分布的影响.方法:模拟5种咬合状态,对涉及牙尖斜度的尖、平、凹3种腭穹隆形态上颌全口义齿的三维有限元模型进行加载.结果:在不同载荷条件下,3种腭穹隆形态上颌全口义齿基托的切牙乳突区、后牙列区及唇系带切迹区部分或全部为应力集中区,且当牙尖斜度为2°时,中线区应力峰值较小,当牙尖斜度为0°或3°时,中线应力峰值明显增大,在所有载荷条件下,不同腭穹隆形态基托的切牙乳突区及后牙列区应力值大小为:尖型＞平型＞凹型.结论:腭穹隆形态及牙尖斜度对上颌全口义齿基托应力分布状况无明显影响,对各应力区应力值大小有影响,上颌全口义齿基托应力的分布及大小与加载方式有关.

Three dimension finite element analysis on the effect of palatal vault shape and cusp inclination on the stress distribution of maxillary complete denture base

Objective:To study the effect of different palatal vault shape and cusp inclinations on the stress distribution in the base of maxillary complete denture. Method:Using three dimensional finite element method(3-D FED),simulating five bite states,putting five loading conditions on 3-D FED model of maxillary complete denture with three different palatal vault shape and three different cusp inclinations. Result:Getting the stress value and multicolor picture of 3-D FE model. Labial frenal notch zone,incisive papilla zone,or posterior teeth zone are the stress concentration zone of the denture base with three different palatal vault shape under five kinds of loading conditions. while the cusp inclination is 20,the maximum stress values of midline zone get smaller,and while the cusp inclination are 0 or 30,the maximum stress values of midline zone get bigger. denture base of upper edentulous jaw with palatal torus has the biggest stress values in incisive papilla zone and posterior teeth zone,the stress values of midline zone in deep palatal vault denture base are the smallest. Conclusion:Palatal vault shape and cusp inclinations can change the value of stress of maxillary complete denture base,but can not change the stress distribution. Loading condition can change the stress distribution and stress value.