Evaluation of the stresses created by dental implants in the mandible reconstructed with free fibula flap by finite element analysis

Biomechanics are significant for bony regeneration and survival of implants in functional maxillary and mandibular reconstruction. The biological response of bones and accrued implant positioning affect implant longevity. There are sufficient studies on the number, diameter and stress distribution of implants in the native mandible and maxilla. However, there is limited information on the fibula free flap and studies are insufficient on the optimum number, position and distribution stresses of implants. The purpose of this study is to assess the stresses that occur after implant surgery with finite element analysis to determine the optimal implant number, size, diameter, and placement in the mandible reconstructed with fibula graft. Different 19 models were evaluated in the study so that accurate placement of implants in reconstructed mandible using fibular flaps to evaluate the optimum stress distributions under 120N vertical force. The Von Missess and Total deformation data obtained from the bicortical and monocortical placements of the implants that the present study placed in different lengths and positions in the mandible reconstructed with a free fibula flap. The results of the study, as the number of implants increases, the stress at the junction with the mandible decreases. Also, Total deformation decreases, Von Misses stress around implant-bone surface decreases. Monocortical or bicortical insertion; does not affect the Total deformation. High stress values were observed in the implants placed monocortical with a distance of 1 mm to the edge. There is a risk of perforation and dehiscence when placed 0.5 mm close to the edge. We think that studies about this issue will have positive effects on the patient's comfort and the active use of restoration and will reduce the complications that may occur after surgery. More studies are needed to evaluate the effects and consequences of stress.