Mandibulectomy remains the treatment of choice for oral cavity squamous cell carcinoma with infiltration of bone and for benign tumors with full mandibular thickness involvement. Although bone resection margins are critical for patient outcomes, intraoperative immediate bone margins assessment is inadequate, and few alternative options have been described. The purpose of this study was to describe the use of an existing intraoperative radiographic system for objective determination of bone resection margins during mandibulectomy. We conducted a retrospective case series of all patients at the Greater Baltimore Medical Center who underwent mandibulectomy and received intraoperative Faxitron radiography from January 1, 2016, to March 1, 2019. Patient characteristics including age, sex, diagnosis, tumor location, clinical and pathologic stage, procedure performed, and bone resection margins were reviewed. A total of 10 patients underwent mandibulectomy with intraoperative radiography. Nine (90%) received surgery for squamous cell carcinoma, with 1 (10%) for ameloblastoma. Out of those with squamous cell carcinoma, tumor location varied, and all were clinically stage T4. Final pathologic margins were negative in all cases (10/10), though in 2 cases, close margins were assessed intraoperatively, leading to further resection or change in operative plan. Intraoperative radiographic assessment of bone resection margins is a promising technique, though further validation is required.