Medication-related osteonecrosis of the jaw (MRONJ) is a side effect in patients taking bone-modifying agents (BMAs), which are highly beneficial for treating osteoporosis and cancer. Bisphosphonates are prescribed to treat secondary osteoporosis in patients with rheumatoid arthritis (RA). We recently encountered two unusual cases of intraoral ONJ in RA patients who had not been treated with a BMA and did not have features of methotrexate- associated lymphoproliferative disorder. Their ONJ stage II bone exposures were treated by conservative therapy, providing good prognoses. These cases indicate that ONJ can occur in RA patients not treated with bisphosphonates. Several risk factors are discussed.
Keywords: bisphosphonate; osteonecrosis of the jaw; rheumatoid arthritis; risk factor.