Purpose: The purpose of this noninferiority study was to determine whether removable or implant-supported fixed dental prostheses restored patients' abilities to preoperative levels after cancer removal in the mandible. Materials and Methods: Ten patients who had undergone mandibular resection to remove cancer and subsequent reconstruction with microvascularized free fibula flaps were examined in this study. Five patients were rehabilitated with removable prostheses and five received implant-supported fixed prostheses. Health-related quality of life was evaluated using the Head and Neck (H&N30) questionnaire. Kruskal-Wallis nonparametric analysis of variance and Tamhane's T2 test were used to analyze results in comparison with a control group composed of 10 subjects with Class I natural dentition. Results: Masticatory efficiency among the three groups of patients differed significantly (P = .003); in particular, that of the patients who received removable prostheses was not inferior to that of the control subjects (P = .019). Analysis of responses to the Head and Neck module of the Quality of Life Questionnaire showed no significant difference between patients with fixed dentures and patients with removable dentures. Conclusions: There is no apparent difference in quality of life between patients using implant-supported fixed prostheses and those using removable prostheses. Regarding masticatory efficiency, when feasible, the use of implantsupported fixed prostheses is recommended in patients who have undergone free fibula flap surgery, although the removable prostheses also were not inferior in patients who underwent no surgery.