We reviewed the records of 27 patients who underwent primary mandibular reconstruction with AO plates to investigate the outcome and complications of this procedure. Immediate soft-tissue flap coverage was required in 26 patients. Early complications were seen in 44% of the patients, with the highest incidence after irradiation (P = 0.02). Late complications were mostly related to tumor recurrence (12). Late complications not associated with recurrence were persistent pain (2), minor infections (3), plate exposure (3), and plate fracture (1). Good to excellent cosmetic results were obtained in all but 1 patient. Full mastication was not possible for any of our patients, and therefore function was not fully restored. Speech and deglutition were mostly influenced by the amount of soft-tissue resection. Mean follow-up was 20 months (range 3 to 52). At last evaluation, 12 patients were alive and free of disease, and 15 were dead of disease or other causes. Our results show that primary mandibular reconstruction with rigid plates is a safe, effective, and reliable technique to restore mandibular continuity and cosmesis. For lateral defects, this method is a viable alternative to free vascularized osseocutaneous flaps.