螺纹形态和螺距对种植体系统应力影响的三维有限元研究

Three dimensional finite element study of stress influence on dental implant system of different thread form and pitch

目的研究根据标准螺纹参数设计的不同螺纹形态和螺距的9种牙种植体受载后牙槽骨及整个种植系统的应力变化,为种植体系统的优化设计及临床应用提供理论依据。方法采用Solidworks软件建立了螺纹形态分别为V形、梯形、锯齿形,螺距分别为0.7 mm、0.8 mm、1.0 mm的9种标准螺纹式种植体模型,配以基台、基台螺丝构成整套种植体系统,根据CT扫描数据重建下颌骨模型,在垂直向和与种植体长轴成15°斜向分别加载100 N力,ANSYS有限元分析软件计算比较种植体系统和周围牙槽骨的应力及位移分布状况。结果综合考虑种植体系统各部件和种植体周围牙槽骨所受应力,9种种植体中,螺纹形态为V形、螺距为0.8 mm的种植体在垂直向和斜向加载时应力较小。9种种植体各部件及周围牙槽骨最大位移量垂直向加载时为2.61μm,斜向加载时为23.78μm,9种种植体的位移差异小。结论螺纹形态为V形、螺距为0.8 mm的种植体力学性能较好。螺纹形态和螺距对种植体系统及周围牙槽骨的位移影响不大。

Objective To study the biomechanical characteristics between bone and the dental implant system of standard thread with three different thread form and pitch,thus to provide theoretical basis for optimization of dental implant system design and clinical application.Methods Nine kinds of standard thread type implant models（Thread form： V,trapezium,zigzag.Pitch： 0.7 mm,0.8 mm,1.0 mm） were designed by solidworks software,and matched with abutments,connecting screws,thus to constitute a complete implant system.Bone model was constructed by CT scanning data,and loaded with 100 N in direction of vertical or in direction of lateral 15°into dental implant axial,and to calculate and compare the stress and displacement distribution of implant system-bone interface by ANSYS finite element analysis software.Results Comprehensive consideration the stress distribution of the implant system components and alveolar bone around implant,in all 9 kinds of implant,the implant in which thread form is V and pitch is 0.8 mm had the best stress distribution by both loading in direction of vertical and lateral.In all implant system components and surrounding alveolar bone,the maximum displacement when vertical loading was 2.61μm,lateral loading was 23.78 μm,the difference of displacement distribution were very small in 9 kinds dental implants analysis.Conclusion The implant system with thread form V and pitch 0.8 mm has the best biomechanical characteristics.The displacement impact in dental implant system and surrounding alveolar bone are small between different thread form and pitch.