Imaging-based stratification of marginal versus segmental mandibulectomy in MRONJ

Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication of antiresorptive therapy. Although surgical intervention is increasingly recommended, the optimal extent of mandibular resection-particularly indications for marginal versus segmental mandibulectomy-remains controversial. Conventional staging systems may not capture qualitative CT patterns that could be associated with surgical outcomes.

This retrospective observational study included 76 patients with mandibular MRONJ who underwent surgical treatment between January 2018 and March 2024. Preoperative computed tomography (CT) images were evaluated for osteolysis, periosteal reaction, and osteosclerosis, and lesions were classified into three imaging-based types (A-C). Treatment outcomes and prognostic factors were analyzed separately for marginal and segmental mandibulectomy.

Marginal mandibulectomy was performed in 46 patients and segmental mandibulectomy in 30 patients. Healing was achieved in 43.5% after marginal mandibulectomy and in 80.0% after segmental mandibulectomy. In the marginal mandibulectomy group, higher imaging-based MRONJ types (Types B and C), denosumab use, malignancy, and absence of sequestrum separation were associated with lower healing rates. In contrast, in the segmental mandibulectomy group, younger age and periosteal reaction were associated with improved healing.

This study suggests that radiological patterns of mandibular MRONJ are associated with surgical outcomes and may complement conventional staging. Although segmental mandibulectomy showed numerically higher healing, interpretation is limited by confounding by indication. CT-based imaging assessment may help anticipate the risk of delayed or incomplete healing after limited resection and support individualized selection of surgical extent. Future prospective studies incorporating standardized imaging evaluation and radiologic-pathologic correlation are warranted.