正畸微植体动态植入过程有限元数值仿真

目的　为研究微植体动态植入过程中周围骨应力分布情况，提出并建立自攻型微植体动态植入有限元模型。方法　利用CBCT数据重建口腔三维实体化模型；利用ABAQUS软件建立种植周围局部模型及微植体三维有限元模型，微植体以40 N轴向推进力，恒定转速0.5 r/s植入颌骨内。结果　成功建立了动态模拟自攻型正畸微植体植入颌骨的三维有限元模型。植入阶段和螺纹位置对骨内应力影响明显。皮质骨最大应力为167 MPa，稳定阶段最大应力为50 MPa；松质骨最大应力为30 MPa。结论　植入阶段和螺纹位置对应力分布影响明显；皮质骨和松质骨内的应力差异明显。可以通过应力特征判断骨质类型，以及种植体周围的骨应力分布情况判断颌骨是否处于合适的种植状态。

Dynamic Implantation Process of Orthodontic Micro-Implant: Ａ Finite Element Numerical Simulation

Objective To study the stress distributions of the surrounding bone during the dynamic implantation of micro-implants, a finite element model of self-attacking micro-implant dynamic implantation was proposed and established. Methods A three-dimensional (3D) oral model was constructed using CBCT data. The local model around the implant and the 3D finite element model of the micro-implant were established using ABAQUS software. The micro-implant was implanted into the jaw with an axial propulsion force of 40 N at a constant speed of 0.5 r/s. Results A 3D finite element model was successfully established to simulate dynamic self-attacking orthodontic microimplant implantation in The jaw bone. The implantation stage and thread position affected the jawbone stress. The maximum stress on the cortical bone was 167 MPa, and the maximum stress at the stable stage was approximately 50 MPa. The maximum stress on cancellous bone was 30 MPa. Conclusions The implantation stage and thread position have apparent influences on stress distribution. The stress difference between the cortical and cancellous bones was evident. The stress characteristics can judge the bone type, and whether the jaw is in a suitable implantation state can be judged by the bone stress distributions around the implant.