Medication-related osteonecrosis of the jaws from once per year intravenous zoledronic acid (Reclast): report of 4 cases.

Osteonecrosis of the jaws is a commonly reported side effect with patients prescribed oral antiresorptive medications to treat osteoporosis and osteopenia. Oral antiresorptive agents are considered as the standard of care for the prevention and treatment of women with postmenopausal osteoporosis. Because of patient's noncompliance of the antiresorptive medications, which may require once-weekly or once-monthly oral ingestion, a new once a year intravenous (IV) infusion of zoledronic acid was recently introduced in the management of osteoporosis. Reports of medication-related osteonecrosis of the jaw (MRONJ) have been reported in patients with cancer treated with multiple doses of IV zoledronic acid. However, there is a paucity of reports occurring with the once-yearly infusion of zoledronic acid (Reclast) for the management of osteoporosis. In this article, we report 4 cases of patients who had a history of long-term oral antiresorptive therapy and now were taking the once-yearly IV zoledronic acid (Reclast) and soon developed MRONJ after completing surgery of the maxilla and mandible.