Osteoradionecrosis of the mandible: a review.

Osteoradionecrosis (ORN) is a complex metabolic and tissue homeostatic deficiency created by radiation-induced tissue injury. Although infection was initially felt to play an important role in its pathogenesis, the role of microorganisms has been relegated to that of a contaminant. Trauma in some cases may provide a possible initiating factor for the process, or in the case of spontaneous ORN, the use of radioactive implants and the higher doses of radiation therapy as practised in the megavoltage era, may have an influence. The role of prevention cannot be over-emphasized. Dental evaluation is an important part of the initial patient assessment. Preservation of good or average teeth is recommended with subsequent regular follow-up and dental care. Post-treatment dental extraction should be minimized and delayed if possible until at least nine-12 months after completion of radiation therapy. Management of ORN requires assessment of the extent, both clinically and radiologically. Conservative management is recommended unless the disease is advanced or progressive. Radiologic evidence of fracture requires surgery. Modern surgical techniques offer satisfactory reconstruction. The role of hyperbaric oxygen remains controversial and limited to centers where hyperbaric techniques exist. The treatment is complex and time-consuming and results are confounded by the concurrent use of local antiseptic/antibiotic measures and surgery.