Michailidis N, Karabinas G, Tsouknidas A, Maliaris G, Tsipas D, Koidis P
Physical Metallurgy Laboratory, Mechanical Engineering Department, Aristoteles University of Thessaloniki, Thessaloniki, Greece.
Biomed Mater Eng. 2013;23(5):317-27. doi: 10.3233/BME-130756.
Although dental implants exhibit only limited failure rates, their fracture is associated to major modifications of the prosthetic treatment and complex surgery for the removal of the remaining embedded implant part. This investigation aims to assess the developing stress fields in the bone-implant interface during mastication and asses the failure modes of oral implants.In order to achieve this, a FEM model of an implant was reverse engineered and virtually loaded at the top of the crown for a force spectrum ranging from 75-225 N in a vertical, horizontal and oblique occlusal direction. The calculated stress fields were compared with clinically retrieved fractured implants with identical geometrical characteristics and the fracture modes of both cases were correlated. The developing stress patterns facilitated the interpretation of the implant failure as the maximum stresses, indicated critical values in both, lingual and buccal sides of the implant-bone interface at a certain critical level of bone resorption, in which failure occurs.
尽管牙种植体的失败率有限，但其断裂与修复治疗的重大改变以及用于移除剩余植入体嵌入部分的复杂手术相关。本研究旨在评估咀嚼过程中骨-种植体界面处的应力场发展情况，并评估口腔种植体的失效模式。为了实现这一目标，对一个种植体的有限元模型进行了逆向工程，并在牙冠顶部施加垂直、水平和斜向咬合方向的75-225 N力谱的虚拟载荷。将计算得到的应力场与临床上回收的具有相同几何特征的断裂种植体进行比较，并将两种情况的断裂模式进行关联。应力模式的发展有助于解释种植体的失效，因为最大应力在一定的骨吸收临界水平下，在种植体-骨界面的舌侧和颊侧均指示出临界值，此时会发生失效。
