There is a need for a detailed investigation of BRONJ of the maxilla and, in particular, of the involvement of the maxillary sinus. The researchers did this study to evaluate the characteristic radiologic and clinical manifestations in patients with maxillary sinusitis and a history of long-term bisphosphonate use.

Fifty-five patients with symptoms consistent with chronic rhinosinusitis who underwent a paranasal sinus CT and had a history of >12 months of bisphosphonate therapy were included in the analysis.

Radiologically and clinically evident chronic rhinosinusitis was noted in twenty-four of the 55 patients, of whom more than half had BRONJ. The maxillary sinus was involved in all twenty-four patients, characterized by unilateral involvement and bony remodeling in the posterior maxillary region. The evidence of osteitis on CT and/or single-photon emission CT was observed in the majority of cases and 12 patients had an oroantral fistula. However, there were no differences in the clinical appearance of the diseases with respect to the radiologic aspects.

The study concluded that besides its well-known effects on the mandible, long-term bisphosphonate use can also affect the maxillary sinus, with typical clinical and radiological manifestations.