Dental Biomechanics
Pedram Akhlaghi; Setareh Khorshidparast; Gholamreza Rouhi
Volume 15, Issue 3 , December 2021, , Pages 263-277
Abstract
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 ...
Read More
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.
Biomechanics / Biomechanical Engineering
Mehran Ashrafi; Farzan Ghalichi; Behnam Mirzakouchaki
Volume 10, Issue 2 , August 2016, , Pages 113-121
Abstract
Nowadays, the use of dental implants in people with osteoporosis is increasing. The consequences of osteoporosis can be important to the success of osteosynthesis devices, prosthetics and dental implants. Using bisphosphonates, which with impressing bone remodeling and decreasing bone catabolic activity ...
Read More
Nowadays, the use of dental implants in people with osteoporosis is increasing. The consequences of osteoporosis can be important to the success of osteosynthesis devices, prosthetics and dental implants. Using bisphosphonates, which with impressing bone remodeling and decreasing bone catabolic activity lead to increase bone formation can be used as a solution to increase bone density in patients with osteoporosis, which normally osteoporosis is considered as a risk to the acceptance of dental implants by alveolar bone. This study examines the effect of different concentrations of bisphosphonates on bone remodeling. By improving bone remodeling model and taking into account the drug concentration effect on bone resorption, drug effect will be considered. For this purpose, 5, 10 and 20 mg of alendronate per implant and control sample are simulated for a period of 360 days. By comparing the results with control sample, with increasing the drug dose, decrease in bone stress, increase in bone density and thus increase in young's modulus was observed.
