Current status of transport-disc-distraction osteogenesis for mandibular reconstruction.

Surgical intervention including composite mandibulectomy is the mainstay of treatment for extrication of disease in patients with neoplasms involving the mandible. The associated morbidities and reduction in quality of life after reconstruction of the mandibular defect are dependent on the quality of the reconstruction. Therefore, alternative treatments, such as distraction osteogenesis, could be a viable option to improve patient outcome. The goal of this technology is to restore bony continuity through the use of in-situ bone in an attempt to create an anatomically correct regenerate that is better than bone grafting or revascularised free-tissue transfer. Distraction osteogenesis involves a three-step process in which bone adjacent to the defect is osteotomised and gradually opened (distracted) with the aid of a mechanical device, followed by formation of new bone with subsequent consolidation. Previous work has shown encouraging results regarding the translation of distraction osteogenesis technology from an animal model to human application, with particular success in the unradiated setting. The major challenge surrounding the use of this technology in head and neck oncological reconstruction will be the effect of radiotherapy on the regenerate bone in patients who have previously received or will need radiotherapy as part of their treatment. Although distraction osteogenesis provides an attractive alternative for reconstruction of mandibular defects, large studies of human populations are needed to further assess the use of this technology and its role in the treatment framework for mandibular neoplasms.