目的 研究跳跃间隙对盾构术种植系统的生物力学影响,以期为后续临床制定跳跃间隙标准提供参考。方法 依据临床特征建立4组跳跃间隙值分别为0,0.5,1,1.5 mm的盾构术种植系统三维模型,赋予对应的材料参数,模拟在特定咬合力工况下各组模型的应力峰值以及应力分布情况。结果 跳跃间隙值为非0,即种植体与保留根片不接触时,种植体和基台应力随着跳跃间隙的增加而增大,根片及牙周膜应力峰值随着跳跃间隙值增加而减小。跳跃间隙值为0时,种植体、基台根片及牙周膜的应力峰值均达到最大,且远超其他组。结论 跳跃间隙值对盾构术种植系统具有明显生物力学影响,建议临床取较大跳跃间隙值。另外建议根片外形边缘做圆角处理,且下缘尺寸不宜过小。
Objective: To study the biomechanical effect of jumping distance on socket-shield technique in dental implants and provide biomechanical guidance for the clinical standards of the technique. Methods: According to clinical features, four sets of three-dimensional models of the SST implant systems with different jumping distance values of 0, 0.5, 1, and 1.5 mm were established in Mimics. Occlusal force and boundary conditions were applied to the models in Abaqus. The peak stress and stress distribution were observed by finite element analysis. Results: When the jumping distance value is non-zero, which means the implant is not in contact with the retained root fragment, the stress of the implant and abutment increases with the increase of the jumping distance. However, when the jumping distance value is 0, the peak stress of the implant and abutment reaches the maximum, far exceeding that of the other groups. The peak stress of root fragment and periodontal membrane decreased with the increase of the jumping distance value. When the jumping distance was 0, the stress peak also reached the maximum, far exceeding that of the other groups. Conclusion: The jumping distance has a significant effect on the SST implant system. According to the results, it is recommended to take a larger jump gap value in clinical practices. In addition, it is recommended that the edge of the root piece be rounded, and the size of the lower edge should not be too small.