Aim: The aim of this retrospective study was to investigate prognostic parameters for the rehabilitation of mandibular continuity defects with free autologous bone and dental implants for patients after intraoral squamous cell carcinoma. Methods: Following potential prognostic factors for implant survival were analyzed: bony bed (local bone versus augmented iliac crest bone), radiation dose (no radiation, <50 Gy, ≥50 Gy) and implant dimensions. Kaplan-Meier survival estimates of the inserted implants were performed. Results: After 5 years, the cumulative survival rate of all investigated implants was 82.6%. Dental implantation into augmented bone resulted in a significantly lower survival rate (78.4%), compared to original local bone (92.8%). Modifications of implant dimensions as well as radiation therapy showed no significant impact on implant survival. Conclusion: For the investigated compromised collective, our results reveal a satisfactory long-term survival rate of dental implants even in augmented bone and underline the value of dental implantation for the functional rehabilitation of cancer patients.