Denosumab is an antiresorptive agent that is found as a humanized antibody, which inhibits the most critical pro-osteoclastogenic factor secreted by the cancer cells and shown to be required for osteoclast formation, function, and development. A severe side effect of denosumab is the osteonecrosis of the jaw (DRONJ). There are only a few studies on DRONJ treatment in the literature. The aim of this case report is to present the successful conservative management of DRONJ observed after tooth extraction at the posterior maxilla following the discontinuation of medication. To our knowledge, this is the first DRONJ case treated with using the ultrasonic piezoelectric bone surgery combined with leukocyte and platelet-rich fibrin (L-PRF) and pedicled buccal fat pad flap (PBFP). Use of ultrasonic bone surgery in combination with L-PRF and PBFP is an alternative treatment method that can be effective in exposed bone coverage and soft tissue healing at the posterior maxillary region in DRONJ patients.