[Osteonecrosis of the jaw and biphosphonates: imaging features]

1) To review the pathophysiology of osteonecrosis of the jaw in patients receiving biphosphonates. 2) To review the imaging findings of osteonecrosis of the jaw and attempt to define pathognomonic imaging features. Materials and methods. Retrospective study of 15 patients with metastatic disease treated with biphosphonates. All available imaging studies including orthopantomograms, CT and bone scans were reviewed simultaneously by two radiologists (FO, DB).

The most frequent imaging finding was osteolysis. Signs of biphosphonate impregnation were frequently observed: areas os osteosclerosis or heterogeneous demineralization due to abnormal bone remodeling. The outer cortex appeared duplicated in one case. Complications including fracture, sequestra, oroantral fistula and sinusitis may also occur.

The imaging features of osteonecrosis remain fairly non-specific. Drug-related osteonecrosis of the jaw should nonetheless be suggested in the appropriate clinical setting in the presence of osteolysis associated with osteosclerosis. Imaging is helpful to assess the extent of the disease and detect complications for improved patient management.