SUMMARY
Objective: Paget’s disease of bone is characterized by a focal increase in boneresorption and accelerated bone formation leading to a weaker and disorganised bone. Bisphosphonates (BPs) have been the treatment of choice of Paget’s disease since the 1990s. Medication related osteonecrosis of the jaw (MRONJ) is a rare event in non oncologic patients. We describe a rare case of Paget’s diseaseinvolving the maxilla with osteonecrosis in a context of bisphosphonate treatment. Case report: an 87-year-old woman presented with 4 episodes of bone necrosis in 15 years. In this case report there is a clear chronologic association between the occurrence of MRONJ and the administration of iv BP for Paget’s disease.Maxillofacial involvement of Paget’s disease occurs in less than 15% of cases. There is a lack of information in the literature about the association of MRONJ and Paget’s disease. Even if osteonecrosis of the jaw could be a consequence of thedisease, in this case, it is more in relation to the BP treatment. Conclusions: Although MRONJ might be considered a rare condition in Paget’s disease, patients prior to starting antiresorptive therapy and in particular iv BPs should have a complete dental examination and panoramic X-Ray. Nemesis relevance: side effect of bisphosphonate treatment