长径比差异对牙种植体-颌骨界面的应力分布影响

目的探讨不同长径比下牙种植体-颌骨界面的应力分布差异,为新型牙种植体结构的设计提供依据。方法运用Geomagic studio、SolidWorks和ANSYS Workbench软件建立下颌骨三维有限元模型,并根据种植体颈部有、无螺纹分成A、B两组进行仿真实验,对下颌磨牙分别施加不同的斜向咬合力和垂直向咬合力,对比分析牙种植体和周围骨组织的应力分布情况。结果长径比相同的情况下,同一种植体模型在斜向载荷作用下的等效应力峰值明显高于垂直载荷;在斜向和垂直两种载荷作用下,A、B组种植体模型应力主要集中于种植体颈部。斜向载荷作用下,A、B组种植体应力变化范围分别为144.74～374.67、161.52～475.38 MPa;垂直载荷作用下,A、B组种植体应力变化范围分别为101.28～187.40、110.08～210.32 MPa,A组种植体模型最大应力显著小于B组。结论临床上医生可根据长径比2.67初步选择标准种植体,同时结合患者颌骨状况进行选择。

The Influence of Length-diameter Ratio Difference on Stress Distribution at Dental Bone-Implant Interface

Objective To investigate the differences in stress distribution at the bone-implant interface of dental implants with different length-diameter ratios, so as to provide references for the design of novel dental implants. Methods The three-dimensional finite element model of mandible was established using Geomagic studio, SolidWorks and ANSYS Workbench software. The mandibular molars were applied with different vertical or oblique forces, to compare and analyze stress distributions on dental implants and the surrounding bone tissues. Results Under the same length-diameter ratio, the maximum peak equivalent stress of implant under oblique loading was significantly higher than that under vertical loading. The Von Mises stresses of implants in Group A and Group B occurred in the neck under oblique and vertical loading. Under oblique loading, the implant stress variation in Group A and Group B was 144.74-374.67 MPa and 161.52-475.38 MPa, respectively. Under vertical loading, the implant stress variation in Group A and Group B was 101.28-187.40 MPa and 110.08-210.32 MPa, respectively. The maximum Von Mises stress of Group A was significantly smaller than that of Group B. Conclusions Dentists should focus on a length-diameter ratio of 2.67 to select the standard implants, and the jawbone quality of patients should be taken into full account.