Department of Prosthodontics and Research Institute of Oral Science, Gangneung-Wonju National University, Gangneung, South Korea.
Department of Dentistry, Uijeongbu St. Mary's Hospital, Catholic University of Korea, Uijeongbu, South Korea.
J Prosthodont. 2019 Feb;28(2):e649-e656. doi: 10.1111/jopr.12661. Epub 2017 Sep 5.
To evaluate the axial displacement of the implant-abutment assembly of different implant diameter after static and cyclic loading of overload condition.
An internal conical connection system with three diameters (Ø 4.0, 4.5, and 5.0) applying identical abutment dimension and the same abutment screw was evaluated. Axial displacement of abutment and reverse torque loss of abutment screw were evaluated under static and cyclic loading conditions. Static loading test groups were subjected to vertical static loading of 250, 400, 500, 600, 700, and 800 N consecutively. Cyclic loading test groups were subjected to 500 N cyclic loading to evaluate the effect of excessive masticatory loading. After abutment screw tightening for 30 Ncm, axial displacement was measured upon 1, 3, 10, and 1,000,000 cyclic loadings of 500 N. Repeated-measure ANOVA and 2-way ANOVA were used for statistical analysis (α = 0.05).
The increasing magnitude of vertical load and thinner wall thickness of implant increased axial displacement of abutment and reverse torque loss of abutment screw (p < 0.05). Implants in the Ø 5.0 diameter group demonstrated significantly low axial displacement, and reverse torque loss after static loading than Ø 4.0 and Ø 4.5 diameter groups (p < 0.05). In the cyclic loading test, all diameter groups of implant showed significant axial displacement after 1 cycle of loading of 500 N (p < 0.05). There was no significant axial displacement after 3, 10, or 1,000,000 cycles of loading (p = 0.603).
Implants with Ø 5.0 diameter demonstrated significantly low axial displacement and reverse torque loss after the cyclic and static loading of overload condition.
评估不同种植体直径在静态和循环过载条件下的种植体-基台组件的轴向位移。
评估了三种直径（Ø4.0、4.5 和 5.0）的内锥形连接系统，采用相同的基台尺寸和相同的基台螺丝。在静态和循环加载条件下评估基台的轴向位移和基台螺丝的反向扭矩损失。静态加载试验组依次承受 250、400、500、600、700 和 800 N 的垂直静态加载。循环加载试验组承受 500 N 的循环加载，以评估过度咀嚼负荷的影响。在拧紧基台螺丝 30 Ncm 后，在 500 N 的 1、3、10 和 1,000,000 次循环加载下测量轴向位移。使用重复测量方差分析和 2 因素方差分析进行统计学分析（α=0.05）。
垂直载荷的增加幅度和种植体的薄壁厚度增加了基台的轴向位移和基台螺丝的反向扭矩损失（p<0.05）。Ø5.0 直径组的种植体在静态加载后的轴向位移和反向扭矩损失明显低于 Ø4.0 和 Ø4.5 直径组（p<0.05）。在循环加载试验中，所有直径组的种植体在 500 N 加载 1 循环后均表现出明显的轴向位移（p<0.05）。在 3、10 或 1,000,000 次加载后，没有明显的轴向位移（p=0.603）。
在循环和静态过载条件下，Ø5.0 直径的种植体表现出明显较低的轴向位移和反向扭矩损失。
