Document Type : Full Research Paper


1 Researcher Engineer, Biomechanics, Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran

2 Assistant Professor, Biomechanics, Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran



Today, the success and failure of treatment by dental implants is influenced by the concept of primary and secondary stability. Primary stability is the capacity of the bone-implant system to withstand the loads, without noticeable damage to the adjacent bone, which may cause the implant to loosen, and thus the implantation process fails. The aim of this study was to develop a micro-finite element (μFE) model and validate it with an in-vitro mechanical test, in order to evaluate the primary stability of dental implants by measuring the stiffness and ultimate load of the bone-implant system through cyclic compressive loading-unloading test. After bone-implant preparation, a quasi-static compressive step-wise loading-unloading cycles, with a displacement rate of 0.0024 mm/s and displacement-controlled were applied to the bone-implant structure with the amplitudes of 0.04 mm to 1.28 mm. Force-displacement curve and the stiffness of the structure in each step then were obtained. Prior to loading, the bony sample was scanned through a μCT device and a μFE model was developed based on the boundary and loading conditions similar to the in-vitro test to predict the force-displacement curve of the structure. Finally, the predicted force-displacement curve from μFE model was compared with the results of the experimental in-vitro test. Results showed that the predicted force-displacement curve from the μFE model is in agreement with the results of the experimental test. The μFE model developed here has the capability to show the overall response of the bone-implant structure under large deformations, and can also be used as a tool to improve the design of the dental implants, with the ultimate goal of increasing the stability of dental implants in immediate loading dental implants.


Main Subjects

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