上前牙区角度基台应用的三维有限元研究
Three-dimensional finite element analysis of angled abutments in anterior maxilla implant restoration

摘要：目的 探索上颌前牙区不同规格种植体在种植修复时使用不同角度的角度基台的效果。方法 建立仿真模型，运用有限元法软件分析不同尺寸的种植体(直径Φ3.5mm、4.0mm、4.5mm，长度L11.5mm和L13mm)，并对不同直径和长度两两组合后，连接不同角度的角度基台(0°、10°、20°、30°)，研究其生物力学性能。结果 随着基台角度增加，各部位应力及应变递增，分布更集中；Φ3.5mm各组在较小角度(10°以下)、Φ4.0mm各组在接近30°角度时已有超过骨弹性阈值的危险，而Φ4.5mm各组皮质骨弹性形变在各基台角度下均在安全范围内。结论 角度基台的使用需考虑种植体直径因素：小直径植体(Φ≤3.5mm)不建议使用角度基台，如需要使用角度基台，需控制咬合力；标准直径(3.5mm<Φ≤4.5mm)和大直径种植体(Φ>4.5mm)可以连接较大角度的基台，同时需控制咬合避免过载。
ABSTRACT: Objective To explore the effects of angled abutments on the anterior maxilla implant restoration. Methods We analyzed the biomechanical properties of implants of different sizes (Φ3.5mm, 4.0mm and 4.5mm in diameter; L11.5mm and L13mm in length) after connecting different angled abutments (0°, 10°, 20°, and 30°) using finite element method. Results The stresses and strains of loading parts of restorations increased and their distribution became more concentrated as the angle of abutment increased. Cortical bone of Φ3.5 implants with smaller angle (10° or less) and Φ4.0 implants with abutments had the risk of overpassing the bone elastic threshold when the angle approached 30°. However, the cortical bone elastic deformation was within a safe range at all angles in Φ4.5 group. Conclusion We should consider the diameter of the implant when selecting angled abutments. The angled abutments are not suitable for small diameter implants. The bite force should be under control when needed. The larger angled abutments can be applied in the standard and major diameter implants and it is necessary to avoid occlusal overloading