Osteoradionecrosis: causes and prevention.

Osteoradionecrosis (ORN) is one of the most serious complications arising from head and neck radiation therapy. Current research has shown that ORN represents nonhealing, dead bone and is not a state of infection. ORN is the result of functional and structural bony changes that may not be expressed for months or years. ORN may occur spontaneously or in response to wounding. Predisposing factors include absorbed radiation dose, fractionation, delivery modality, and dental status. Timing of dental extractions and other factors have also been shown to affect incidence. ORN may be reduced through early intraoral evaluation, treatment, and adequate healing time prior to beginning RT. Hyperbaric oxygen (HBO) therapy has been beneficial in the prevention and treatment of ORN. It is of paramount importance for the medical community to recognize the factors that may reduce ORN incidence, endorse oral care protocols, and acknowledge the value of HBO therapy in the prevention and treatment of this disease.