Reconstruction of Posterior Mandibulectomy Defects in the Modern Era of Virtual Planning and Three-Dimensional Modeling

BACKGROUND Posterior mandibulectomy defects can be reconstructed using either soft tissue or vascularized bone. The authors hypothesize that advances in computer-aided design and manufacturing (CAD-CAM) have resulted in osteocutaneous free flaps now proving superior to soft-tissue flaps. METHODS The authors conducted a retrospective review of all free flap reconstructions of posterior mandibulectomy defects where the condyle was resected from 2005 to 2016. RESULTS Overall, 291 patients (mean age, 56.9 years; mean body mass index, 26.2 kg/m) underwent posterior mandible reconstruction with 169 soft-tissue flaps and 122 osteocutaneous free flaps (90 free-hand versus 32 CAD-CAM). Forty patients (13.7 percent) required two free flaps to reconstruct the defect, most commonly a fibula osteocutaneous flap for the mandibulectomy defect and a soft-tissue flap for external coverage. Postoperatively, there were no differences in the incidence of trismus between soft-tissue versus vascularized bone flaps; however, malocclusion was most common in patients with soft-tissue flaps (p < 0.001). Patients with CAD-CAM bone reconstruction experienced significantly less malocclusion (p < 0.001), were more likely to progress to a regular diet (p = 0.001), and trended to having superior speech (p = 0.057) compared with the other cohorts. There were six total flap losses, with no difference between soft-tissue and bony flaps. CONCLUSIONS Although reconstruction of posterior mandibulectomy defects should be based on the patient's comorbidities, surgeon comfort, and available resources, patients undergoing reconstruction of posterior mandibulectomy defects reconstructed with CAD-CAM-assisted fibulas experienced superior postoperative function compared with soft-tissue flaps or free-hand fibula flaps. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, III.