目前,牙科假体是一种有效的解决方案,可以替代潜在的牙齿缺失或牙齿缺失的临床状况。然而,口腔是一个动态而复杂的系统:咬合负荷,外部代理人,或其他不愉快的事件可能会影响植入物的功能和稳定性,导致未来的翻修手术。失败的起源之一当然是源于日常口腔活动的动态负荷,例如进食,咀嚼,等等。本文的目的是评估,通过基于有限元方法(FEM)的数值分析,以比较的方式讨论,首先,两种不同采用的牙科植入物的应力应变,随后,它们的疲劳寿命根据通用的计算标准。为了这次调查,对颌骨进行建模,以考虑各向同性或各向异性行为。它由皮质和松质区域组成,考虑到它与植入物完全骨整合。植入物夹具设计的影响,加载条件,最后研究了它们对下颌骨的影响,在得到的数值结果的基础上。最后,所研究的植入物的生命周期是根据古德曼的既定理论进行估计的,索德伯格,和Gerber通过利用数值模拟获得的结果,提供对牙科实践有用的有趣结论。
Dental prostheses are currently a valid solution for replacing potential missing tooth or edentulism clinical condition. Nevertheless, the oral cavity is a dynamic and complex system: occlusal loads, external agents, or other unpleasant events can impact on implants functionality and stability causing a future revision surgery. One of the failure origins is certainly the dynamic loading originated from daily oral activities like eating, chewing, and so on. The aim of this paper was to evaluate, by a numerical analysis based on Finite Elements Method (FEM), and to discuss in a comparative way, firstly, the stress-strain of two different adopted dental implants and, subsequently, their fatigue life according to common standard of calculations. For this investigation, the jawbone was modeled accounting for either isotropic or anisotropic behavior. It was composed of cortical and cancellous regions, considering it completely osseointegrated with the implants. The impact of implants\' fixture design, loading conditions, and their effect on the mandible bone was finally investigated, on the basis of the achieved numerical results. Lastly, the life cycle of the investigated implants was estimated according to the well-established theories of Goodman, Soderberg, and Gerber by exploiting the outcomes obtained by the numerical simulations, providing interesting conclusions useful in the dental practice.