Postoperative Recurrence of Medication-Related Osteonecrosis of the Jaw: A Retrospective Study of 150 Patients Undergoing Surgery.

Introduction Surgery is the recommended treatment for medication-related osteonecrosis of the jaw (MRONJ). However, the disease may recur postoperatively. We reviewed imaging findings in patients undergoing three or more surgeries. Patients and methods One hundred fifty patients with MRONJ underwent surgery at our hospital. Here, we present the characteristics of 34 surgeries in nine patients (two men and seven women; mean age, 73.9 years) who underwent surgery at least three times. Results Three and six patients had maxillary and mandibular lesions, respectively. The primary disease was malignancy in eight patients, and denosumab was used in seven patients. All patients initially underwent either partial maxillectomy or marginal mandibulectomy, and segmental mandibulectomy was not performed. The number of surgeries ranged from three to six (average, 3.8). Healing was eventually achieved in seven cases, but not in two cases. Of the 27 unsuccessful surgeries, postoperative cone-beam computed tomography revealed no residual osteolysis, periosteal reaction, or osteosclerosis after seven surgeries and some residual lesions after 19 surgeries; imaging was not performed after one surgery. In contrast, among the seven successful surgeries, no residual osteolysis, periosteal reaction, or osteosclerosis was observed in all six cases in which postoperative computed tomography was performed. Conclusion Recurrence is more common in patients with residual areas of osteolysis, periosteal reactions, or mixed-type osteosclerosis, and including these areas in the resection is desirable.