Purpose: To report a case of osteonecrosis of the jaw (ONJ) occurring in an implant area possibly related to denosumab, a relatively new antiosteoporotic agent. Materials and methods: Two months following the extraction of both maxillary first molars, a bilateral maxillary sinus floor elevation was performed on a 64-year-old female patient under a biannual 60 mg denosumab antiosteoporotic treatment. Seven months later, two implants were inserted in a single-stage procedure in each of the grafted sinuses. After 3 months, the implants underwent prosthetic rehabilitation at one side, and a series of failures that led to an ONJ instalment at the other side. Results: The ONJ persisted over 7 months and was only resolved by a surgical approach consisting of a piezoelectric osteotomy and platelet-rich fibrin with a tension-free wound closure. Conclusions: A cumulative effect of denosumab is likely to be associated with a jaw osteonecrosis, which in this case was manageable using a surgical approach with no need to interrupt the appropriate drug treatment course.