Pektaş Ömer, Tönük Ergin
Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey Genamer Technology Ltd., Ankara, Turkey.
Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey Graduate Program of Biomedical Engineering, Middle East Technical University, Ankara, Turkey BIOMATEN - Center of Excellence in Biomaterials and Tissue Engineering, Middle East Technical University, Ankara, Turkey
Proc Inst Mech Eng H. 2014 Nov;228(11):1117-25. doi: 10.1177/0954411914557713. Epub 2014 Nov 4.
At the interface between the jawbone and the roots of natural teeth, a thin, elastic, shock-absorbing tissue, called the periodontal ligament, forms a cushion which provides certain flexibility under mechanical loading. The dental restorations supported by implants, however, involve comparatively rigid connections to the jawbone. This causes overloading of the implant while bearing functional loading together with neighboring natural teeth, which leads to high stresses within the implant system and in the jawbone. A dental implant, with resilient components in the upper structure (abutment) in order to mimic the mechanical behavior of the periodontal ligament in the axial direction, was designed, analyzed in silico, and produced for mechanical testing. The aims of the design were avoiding high levels of stress, loosening of the abutment connection screw, and soft tissue irritations. The finite element analysis of the designed implant revealed that the elastic abutment yielded a similar axial mobility with the natural tooth while keeping stress in the implant at safe levels. The in vitro mechanical testing of the prototype resulted in similar axial mobility predicted by the analysis and as that of a typical natural tooth. The abutment screw did not loosen under repeated loading and there was no static or fatigue failure.
在颌骨与天然牙牙根的界面处，一种名为牙周韧带的薄而有弹性、能吸收冲击的组织形成了一个垫子，在机械负荷下提供一定的柔韧性。然而，由种植体支持的牙齿修复体与颌骨的连接相对刚性。这会导致种植体在与相邻天然牙共同承受功能负荷时过载，从而在种植体系统和颌骨内产生高应力。设计了一种在上部结构（基台）中有弹性部件的牙种植体，以模拟牙周韧带在轴向的力学行为，并进行了计算机模拟分析，随后制造出来进行力学测试。该设计的目的是避免高应力水平、基台连接螺钉松动以及软组织刺激。对设计的种植体进行有限元分析表明，弹性基台在使种植体内应力保持在安全水平的同时，产生了与天然牙相似的轴向移动性。原型的体外力学测试结果显示，其轴向移动性与分析预测的以及典型天然牙的轴向移动性相似。基台螺钉在反复加载下未松动，也没有出现静态或疲劳失效。
