A study of factors contributing to the development of osteoradionecrosis of the jaws.

The histories of 14 patients in whom osteoradionecrosis developed were compared with those of 28 patients who had similar tumors and/or treatment and were not afflicted with osteoradionecrosis. 1. Fourteen of 15 episodes of bone complications occurred in the mandible, and 70% occurred within 1 year after the completion of radiation therapy. 2. A high dose of radiation, with conventional fractionation, did not specifically predispose patients to osteoradionecrosis. Fifty percent of the ORN patients actually received a total dose of 6000 rad or less. Combined radiation therapy and surgery did not seem to significantly increase the risk inasmuch as both groups of patients had similar combinations. In two of four patients who received methotrexate, however, osteoradionecrosis developed during the time of administration. 3. One of the most prevalent negative factors associated with the ORN patients was the continued heavy use of alcohol and tobacco by 86% of them. These strong tissue irritants could have significantly contributed to the breakdown of mucosa and exposure of bone. Alcohol and tobacco could also have potentiated the combined effects of the other negative factors, such as contributing to poor oral hygiene. 4. The ORN patients had poorer oral hygiene than the control group. Seventy-five percent of the patients with teeth who had osteoradionecrosis continued to have poor oral hygiene. In contrast, none of the control patients had poor oral hygiene. 5. A combination of factors relating to stage of tumor and treatment was found in the ORN patients.(ABSTRACT TRUNCATED AT 250 WORDS)