The most frequent type of treatment for patients diagnosed with a malignant neoplasia of the oral cavity is surgical removal of the tumor. As a result of the resection performed, it is difficult to obtain satisfactory results in the oral rehabilitation of these patients. When possible, fixed prostheses are the best option, because they guarantee stability, but they should be made so that the operator can remove them periodically to check the health of the oral tissues underneath and to intercept any relapse of the tumor. This study analyses two cases of patients surgically treated for a tumor of the upper maxilla at the Oral and Maxillo-Facial Surgery of Sapienza University, in Rome. In the first case the surgical site was covered with local flaps, and the patient was rehabilitated with an implant-supported removable prosthesis. In the second case the maxilla was reconstructed with a fibula vascularized free flap, and the patient was rehabilitated with an implant-supported prosthesis screwed to a titanium bar solidarizing the implants. Therefore, this prosthesis was fixed, but could be removed by the dentist. The different approach to these two cases was influenced by the different anatomic situations after the reconstruction. It is important for the dentist to approach these patients knowing the kind of surgery they received because this aspect will influence rehabilitative choices. Rehabilitation should be planned, when possible, before surgical treatment, in order to cooperate with the maxillo-facial surgeon in choosing the most appropriate restorative treatment.