Plate fixation strategies for fibular reconstruction following segmental mandibulectomy: A comparative study of double-barrel and single-barrel techniques.

Purpose: Mandibular defects following oncological resection present significant aesthetic and functional challenges due to the loss of bone and soft tissue. Immediate reconstruction is crucial to prevent complications such as malocclusion, mandibular deviation, temporomandibular joint dysfunction, and impaired mastication, swallowing, and speech. Although the fibula flap is widely used, its limited vertical height complicates alveolar arch restoration in dentate mandibles. The double-barrel fibula flap addresses this limitation; however, the biomechanical stability of various fixation methods remains underexplored. Methods: Finite element analysis was performed using computed tomography data from a patient with T4 mandibular gingival carcinoma. Five fixation configurations were evaluated: four short plates, one long plate with two short plates, two box plates, a custom-designed long box plate, and a single-barrel model. Simulated masticatory forces and boundary conditions were applied, with material properties assigned through Hounsfield unit conversion and established literature values. Results: Stress concentrated at the fibula-mandible junction, particularly at the proximal interface and along the inferior border. The long + two-short-plate configuration demonstrated the lowest stress. Custom plates reduced displacement and altered stress distribution. Single-barrel models consistently exhibited higher stress and displacement. Conclusions: Integrating the fibula with the proximal and distal mandibular segments using a long plate positioned along the inferior border enhances stability. Incorporating a three-dimensional plate structure may further reduce displacement. Double-barrel reconstruction offers superior biomechanical stability compared with single-barrel techniques.