Objective: The aim of this study was to investigate the frequency of osteoradionecrosis/medication-related osteonecrosis of the jaw (ORN/MRONJ) after dental extraction with use of postextraction antibiotic coverage without prophylactic hyperbaric oxygen (HBO) in patients who received radiotherapy to head and neck (RT-HN) or antiresorptive medications and to determine possible associated factors.

Study design: A retrospective study was conducted in patients who had a history of RT-HN or exposure to antiresorptives and who underwent dental extractions from 2003 to 2019. According to the clinical protocol, patients received amoxicillin 500 mg, 3 times daily (TID) for at least 14 days, and chlorhexidine 0.12% rinses, 2 times daily (BID), after extraction (or an alternative antibiotic if allergic to amoxicillin). HBO was not used for patients with RT-HN.

Results: Ninety patients underwent a total of 243 extractions. Fifty patients (55.5%) received a median of 54.1 Gray to the extraction site and 40 (44.4%) were on antiresorptives. None of the patients received both RT and antiresorptives. Of 40 patients, 3 (7.5%) developed MRONJ, and of 50 patients, 1 (2%) developed ORN. Among those at risk for MRONJ, male gender and concomitant immunosuppressant medications were associated with MRONJ development (P < .05).

Conclusions: In our patient cohort, the rate of postextraction ORN/MRONJ was lower and comparable with the rates reported in the literature. Larger prospective studies are required to validate the efficacy of postextraction antibiotics in reducing ONJ.