Purpose: Osteoradionecrosis of the mandible is a debilitating consequence of radiation therapy for head-and-neck malignancy. It can result in pain, bone exposure, fistula formation, and pathologic fracture. Recombinant human bone morphogenetic protein 2 (rhBMP-2) has shown promise in reconstruction of bone defects. The purpose of this study is to determine whether the addition of rhBMP-2 at the union of vascularized bone and native bone improves surgical outcomes in patients with osteonecrosis of the mandible. Materials and Methods: This study was a retrospective analysis of patients who were treated between 2006 and 2010 for osteonecrosis of the mandible. Patients requiring definitive reconstruction after failure of a course of conservative management were included. Patients were divided into 2 cohorts depending on whether rhBMP-2 was used during the reconstruction. The primary outcome measure was defined as stable mandibular union. Results: Seventeen patients were included. The development of malunion was similar in both groups (13% for rhBMP-2 group vs 11% for non-rhBMP-2 group). Infectious complications were similar between the groups (25% in rhBMP-2 group vs 56% in non-rhBMP-2 group, P =.33). The rates of hardware removal were similar for the 2 groups (33% in non-rhBMP-2 group vs 25% in rhBMP-2 group, P =.10). No cancer recurrences were observed in patients receiving rhBMP-2. Conclusions: The use of rhBMP-2 is safe in free flap reconstruction of the mandible, but its ability to significantly improve patient outcomes, as measured by rates of malunion, reoperation, or infection, is still unknown. © 2012 American Association of Oral and Maxillofacial Surgeons.