纳米羟基磷灰石/聚醚醚酮复合种植体受力的三维有限元分析

Stress Distribution of Nano-hydroxyapatite/Polyetheretherketone Compound Implant:a Three-dimensional Finite Element Analysis

目的:评价纳米羟基磷灰石/聚醚醚酮(Nano-hydroxyapatite/Polyetheretherketone,n-HA/PEEK)仿生种植材料受力时种植体及其周围骨组织的应力特征,为该种植材料的临床运用提供生物力学依据。方法:根据CT扫描数据及种植体产品数据建立包括牙槽骨、种植体的三维有限元模型,比较在150N垂直加载条件下n-HA/PEEK和钛种植体周围骨皮质及骨松质的应力分布。结果:两种材料应力分布规律:紧邻种植体颈部的骨皮质应力最大远离处逐渐减小,皮质骨内两种材料的表面最大应力有显著性差异(P<0.05)。负重时钛金属种植体其表面应力波动变化范围增大,容易形成应力集中。同骨组织具有相似弹性模量的n-HA/PEEK材料表面应力分布更均匀。结论:n-HA/PEEK材料更有利于将种植体所受载荷以应力的形式传递到周围骨组织中去,有利于保持骨结合面的长期稳定。

Objective：To study the stress distribution of nano-hydroxyapatite/polyetheretherketone（n- HA/PEEK）bionic implant and the alveolar bone surrounding the implant,and to provide biomechanical basis for clinical application of the implant.Methods：According to CT scan and implant product data,a three-dimensional finite element model with a implant and its surrounding alveolar bone was set up.The stress distributions of cortical bone and cancellous bone surrounding both n-HA/PEEK and titanium implants were compared when bearing vertical loading of 150 N.Results：The stresses of the cortical for the two implants were the largest at the implant necks,and decreased as the bone cortex got away from the neck.In the cortical bone there are significant differences between the maximum stress on the surface of the two implants（P〈0.05）.The range of stress fluctuation on the load-bearing titanium implant surface increased,and it was prone to form stress concentration.The surface stress of n-HA/PEEK materials,which shared similar elastic modulus with bone tissue,distributed more uniformly.Conclusion：N-HA/PEEK material is more conducive to transfer the load to the surrounding bone tissue in the form of stress,which is helpful to maintain the long-term stability of implant and bone interface.