Bisphosphonate is used to treat osteoporosis, bone metastases, hypercalcemia of malignancies and multiple myeloma.

Bisphosphonate related osteonecrosis of the jaw (BRONJ) is defined as exposed necrotic bone in the maxillofacial area that persists for more than 8 weeks in patients with a history of nitrogen-containing bisphosphonate use without a history of radiation exposure. Patients present with pain, swelling, purulent secretions, paresthesia, and difficulty in eating.

Image features of BRONJ are osteolysis, osteosclerosis, sequestration, periosteal reaction and spreading of soft tissue inflammation.

The top differential diagnosis is osteoradionecrosis, which has almost indistinguishable imaging features. Patients report a history of radiotherapy.