Image findings of bisphosphonate related osteonecrosis of jaws comparing with osteoradionecrosis

Objectives: The aim of this study was to evaluate image characteristics of bisphosphonate-related osteonecrosis of the jaws (BRONJ) and compare these with osteoradionecrosis (ORN). Methods: 34 patients with BRONJ and 16 patients with ORN were included in this study. We investigated the CT and dental panoramic radiograph (DPR) images for osteolysis, osteosclerosis, sequestration, periosteal reaction, pathological fracture and spread of soft tissue inflammation around the jaws. Results: Osteolysis, osteosclerosis, sequestration and spread of soft tissue inflammation around the jaws were common radiological features in both BRONJ and ORN. Osteolysis and spreading of soft tissue inflammation around the jaws were predominant in ORN, and by contrast osteosclerosis was predominant in BRONJ. Periosteal reaction was established in 15 of the 34 BRONJ cases, but none in the ORN cases. Pathological fractures were observed in 6 of 16 ORN cases, but none in BRONJ cases. CT was better for detection than DPR for osteolysis, osteosclerosis, sequestration and periosteal reactions. Conclusions: Image findings of BRONJ were characterized as a severe sclerotic change combined with osteolysis, sequestration, periosteal reaction and spread of soft tissue inflammation around the jaws.