Bisphosphonate - related osteonecrosis of the jaws: the point of view of the oral pathologist.

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is mainly reported in patients with bone metastasis from a variety of solid tumors and disseminated multiple myeloma receiving iv bisphosphonates therapy. These patients represent 95% of reported cases. The reported incidence of BRONJ is significantly higher with the iv preparations zoledronic acid and pamidronate while the risk appears to be minimal for patients receiving oral bisphosphonates. Currently, available published incidence data for BRONJ are based on retrospective studies and estimates of cumulative incidence range from 0.8% to 12%. The mandible is more commonly affected than the maxilla (2:1 ratio), and 60% of cases are preceded by a dental surgical procedure. The signs and symptoms that may occur before the appearance of clinical evident osteonecrosis include changes in the health of periodontal tissues, non-healing mucosal ulcers, loose teeth and unexplained soft-tissue infection. Although the definitive role of bisphosphonates remains to be elucidated, the alteration in bone metabolism together with surgical insult or prosthetic trauma appear to be key factors in the development of BRONJ. Tooth extraction as a precipitating event is a common observation in the reported literature. The significant benefits that bisphosphonates offer to patients clearly outbalance the risk of potential side effects; however, any patient for whom prolonged bisphosphonate therapy is indicated, should be provided with preventive dental care in order to minimize the risk of developing this severe condition. This article provides a review of current developments about the pathogenetic, clinical, management and preventive aspects of BRONJ.