种植体周围骨内应力分布的三维有限元分析

目的针对不同类型的牙槽骨科学地选用种植体,提高种植体临床疗效,延长使用寿命。方法采用三维有限元分析方法,将圆柱状、螺纹状和台阶状种植体分别植入4类骨质结构中,对此12种情况进行应力分析。结果在同种骨质模型中,圆柱状种植体颈部周围骨内的应力集中最小;就同种形态种植体而言,较低的骨质密度不利于种植体的应力分布。结论圆柱状是一种最有利于降低颈部骨质吸收的形态结构。螺纹状种植体周围骨内应力最大值大于圆柱状,而螺纹自身非力学优势极大的拓展了该型种植体的使用范围,但螺纹尖端处的高应力区域和螺纹之间的低应力区域是影响其长期使用效果的潜在不利因素。台阶状种植体相对较适合骨质好的情况,其根部出现局部高应力区域,若应力处于骨生理承受范围之内,将有利于减少根部骨质疏松。

Stress distribution in bone around dental implants studied by three-dimensional finite element analysis

Objective:To study the stress distribution in bone with different densities around dental implants in different shape.Methods:Dental implants in the shape of cylinder,thread and steps were implanted into the mandibular bone at the position of the first molar with 4 different densities respectively.Three-dimension finite element models were rebuilt and stress distribution in the bone around implants were investigated. Results:In the same load and bone density conditions, cylindrical implant resulted in lowest peak stress value,the same implant in mandibular bone with higher density produced lower stress peak value.Conclusion:Dental implatns in the shape of cylinder and higher density of the bone around the implant may reduce stress concentration.