Bisphosphonate-related osteonecrosis of the jaw (BRONJ) associated with a once-yearly IV infusion of zoledronic acid (Reclast) 5 mg: two cases and review of the literature.

The use of a once-yearly IV infusion of 5 mg zoledronic acid has become more common, as the drug is being reported as safe, with few to minimal adverse reactions. This one-time annual administration has a favorable outcome for patients with osteoporosis and spares the burden of taking daily oral bisphosphonates. The present literature search found 10 well-documented cases of bisphosphonate-related osteonecrosis of the jaw (BRONJ) associated with annual administration of 5 mg zoledronic acid for the treatment of osteoporosis. Two new cases are also described, with underlying risk factors similar to previous reports. These include prior dental surgical procedures, the presence of diabetes, autoimmune conditions, past use of bisphosphonate and steroids, and concomitant immunosuppression. Although the reported incidence of BRONJ related to once-a-year IV administered zoledronic acid is low, it may be plausible. Both medical and dental clinicians should be aware of its manifestation.