上颌中切牙角度基台不同载荷的三维有限元优化分析

Three-dimensional finite element analysis of different abutment angles and loads of the maxillary central incisor

背景:口腔种植修复中,种植体中基台角度的优化设计对骨吸收有重要影响,同时患者的高用力也对骨质的吸收重建有着重要影响。目的:利用Ansys Workbench 13.0软件对上颌骨前牙区进行优化设计模型,探讨中切牙角度基台不同载荷对皮质骨和松质骨应力大小的影响。方法:建立圆柱状V形螺纹种植体的上颌骨骨块三维有限元模型,设定基台角度为0°,5°,10°,15°,20°、25°,30°,设定加载应力为90,105,120,135,150,165,180,195,210 N。在种植体上模拟中切牙咬合,在修复体正中进行颊舌向力学加载,观察基台角度和加载应力变化对颌骨Von Mises应力峰值的影响。结果与结论:单因素影响下,以基台角度为变量逐渐增加时,在唇腭侧向加载中皮质骨和松质骨的Von Mises应力峰值增幅分别为60.63%和69.30%;以加载应力为变量逐渐增加时,在颊舌向加载中皮质骨和松质骨的Von Mises应力峰值增幅分别为68.74%和69.30%。在基台角度和加载应力交互作用下,当加载应力小于150 N,同时基台角度小于25°时,对颌骨Von Mises应力峰值响应曲线的切线斜率位于-1至0之间。所以从力学分析看来,松质骨的应力大小更易受到基台角度和加载应力的影响,螺纹种植体最佳的基台角度设计应小于25°,咬合力应小于150 N。

BACKGROUND： To optimize the oral implant design in the abutment angle has an important effect on bone resorption, and meanwhile, the high bite force from patients is also crucial to rebuild bone absorption. OBJECTIVE： To optimize the model design of the maxillary anterior teeth using Ansys Workbench 13.0 software and to investigate the stress size on the cortical and cancellous bone from different angled abutments and different loads of the central incisor. METHODS： A three-dimensional finite element model of the V-shaped cylindrical threaded implants in the maxillary bone. Abutment angle was set as 0°, 5°, 10°, 15°, 20°, 25°, 30°, and the load stress was set as 90, 105, 120, 135, 150, 165, 180, 195, 210 N. Occlusion of the central incisor was simulated on the implants, and then, buccolingual mechanical loads were loaded on the center of prostheses to observe the effects of different abutment angles and loads on the Von Mises peak stress of the maxilla and mandible. RESULTS AND CONCLUSION： Under the influence of a single factor, when the abutment angles acted as variables, the Von Mises peak stress of the cortical and cancellous bone was respectively increased by 60.60% and 69.30% under labial or palatal loads; when the loading stress acted as variables, the Von Mises peak stress of the cortical and cancellous bone was increased by 68.74% and 69.30% under buccolingual loads. When the loading stress was less than 150 N and the abutment angle was less than 25°, the slop of tangent for the mandible Von Mises stress response curve was-1 to 0. It seems from the mechanical analysis that the stress of cancellous bone is more susceptible to abutment angle and load stress; the optimal abutment of screwed implant should be designed to an angle less than 25° and an bite force less than 150 N.