To report our clinical experience using bifocal distraction osteogenesis (BDO) with internal devices to treat patients having bony defects of the maxillofacial skeleton following tumor ablation and to focus on outcomes of dental implant placement in patients having maxillomandibular segmental defects.
Retrospective case series.
Patients were selected according to the following inclusion criteria: a bony defect in the maxillofacial skeleton, moderate soft-tissue defect, local or general conditions that preclude more aggressive surgery, and adequate patient compliance. Types of BDO included horizontal mandibular or maxillar alveolar, bilateral alveolar, vertical mandibular or maxillar, ramus and body, mandibular angle, symphysis, the 2-step procedure, temporalis muscle flap reconstruction, vascularized free–fibular flap reconstruction, radial forearm free-flap reconstruction, and pectoralis muscle flap reconstruction.
Main Outcome Measures
The latency period was 10 days, after which distraction was initiated at a rate of 0.5 mm/d. The distraction period continued until the transport disk reached the distal stump. The consolidation period ranged from 8 to 48 weeks. Seven patients required additional bone grafting to complete union with the residual bone.
Twenty-eight patients having bony defects of the maxillofacial skeleton underwent BDO. The mean (SD) bony defect length was 47.0 (20.1) mm. The mean (SD) distracted bone lengthening was 36.5 (20.0) mm, with a mean (SD) consolidation period of 16.4 (8.0) weeks. The bony defect involved the hemimandibular body in 12 patients, with greater involvement of the body and symphysis in 4 patients and of the bilateral mandibular body in 2 patients. Complications after BDO included the following: discomfort in 8 patients, complete intraoral exposure and infection in 3 patients, partial cutaneous exposure in 1 patient, premature consolidation in 1 patient, and temporomandibular joint ankylosis in 1 patient. Overall, BDO for reconstruction of bony defects was successful in 22 patients and failed in 6 patients. At the end of the follow-up period, 11 patients had undergone endosseous dental implant placement.
Bifocal distraction osteogenesis potentially benefits patients with bony defects following tumor ablation at various locations in the maxillofacial skeleton. Sufficient bone is gained to allow dental implant placement, an important functional outcome.