Three-dimensional Finite Element Analysis of Implant Prosthesis After Mandibular Reconstruction by Upper Distal Free Double-Barrel Fibula

Objective: This study aimed to compare the biomechanics of implant prostheses and peri-implant bone among 6 different mandibular reconstruction models based on patient data involving the use of an upper free-end double-barrel fibula. Methods: This study was an observational study. Five models were reconstructed using fibular-supported and implant-supported partial dentures. Two of these models were double-barrel fibula models with different gaps between the upper and lower segments. The other 2 were single-layered fibular models (the fibula was placed at the inferior or superior mandibular borders). The fifth model was a double-barrel fibula with a free distal end on the upper segment. In addition, a typical mandibular model was created for comparison. Two fixed partial-denture models were used in this study. The von Mises stress and strain of the models were analyzed. Results: The maximum stress decreased with increasing gap between the upper and lower fibula. The distal free-end double-barrel fibula showed a potential to reduce the maximum stress around the implant apex while increasing it around the implant neck compared with a fixed distal-end double-barrel fibula. Conclusions: Utilizing a free distal end on the upper fibula may be a viable option for mandibular reconstruction, especially when the fibula length is limited.