A brief review: characteristics of bisphosphonate-related osteonecrosis of the jaw (BRONJ) from the viewpoint of pathology

Bisphosphonate (BP) is widely used for the treatment of bone diseases, including osteoporosis. Osteonecrosis of the jaw occurring in patients receiving BP is suggested to indicate an association of osteonecrosis with BP treatment, and hence BP-related osteonecrosis of the jaw (BRONJ) is proposed as a disease condition. The pathogenesis of BRONJ is uncertain, but several predisposing factors have been identified. BRONJ is characterized by bone necrosis, inflammation, and infection, but the sequence of events leading to the bone exposure has not been established. Here, we present a case of BRONJ with radiologic and pathologic correlations, and review its characteristics and putative mechanism for the onset of BRONJ from the viewpoint of pathology.