Osteoradionecrosis of the jaws: Clinical characteristics and relation to the field of irradiation

Purpose: This study focuses on the clinical characteristics of patients wit h osteoradionecrosis (ORN) of the jaws and on the relation between the exte nt of the ORN and the field of irradiation. Patients and Methods: The study group consisted of 80 patients referred for treatment of ORN. Charts of the extent of ORN, based on panoramic radiogra phs, were drawn by the clinical investigator and compared with charts of th e field of irradiation drawn by the oncologists. Also recorded was diagnosi s of the lesion, stage, location, treatment schedule, and period and dose o f irradiation. Also documented were various potential initiating factors fo r ORN. Results: Smoking habits of ORN patients were similar to those of other pati ents with head and neck cancer. A new primary tumor or a recurrence was dia gnosed in 10% of the patients at the time of ORN. Only 3 patients had recei ved accumulated doses of less than 60 Gy. More than half of the cases were initiated by removal of teeth; however, one third occurred spontaneously. O RN developed within the first 3 years in 74%; but ORN can emerge on a traum atic basis for an infinite number of years after radiation therapy. Widespr ead ORN may be symptomless apart from a discrete dehiscense of the oral muc osa. The predilection site for ORN is the mandibular molar region. All case s of ORN but 1 were found in the field of radiation. Conclusion: Because many ORN case are symptomless, more focus on mucosal de hiscence in the follow-up after radiation therapy is advocated in an effort to detect ORN at an early stage. The consequence of practically all ORN ca ses being located in the field of irradiation, together with tooth removal frequently being the initiating factor, should lead to a more aggressive pr eirradiation approach to dental pathology located within the field of radia tion. (C) 2000 American Association of Oral and Maxillofacial Surgeons.