Purpose: The purpose of this study was to compare the maintenance requirements of implant-supported fixed prostheses with cantilever arms in edentulous jaws when opposed by fixed prostheses of similar design, by natural teeth, or by complete dentures. Materials and Methods: The maintenance requirements for the 5-year follow-up period were obtained by examining the dental records of 37 people. Six were provided with fixed prostheses in both arches, 22 with a fixed prosthesis in the mandible opposed by a complete denture, and 9 with a fixed prosthesis opposed by natural teeth. Everyone was treated with Nobel Biocare implants using standard implant and prosthetic protocols. Results: The denture teeth and acrylic resin were repaired on 44 occasions in the group with implants in both jaws, on 14 occasions in the group with implants opposed by natural teeth, and twice in the group in which the implants were opposed by a complete denture. The group with implants in both jaws was more likely to fracture the gold-alloy framework, which occurred on six occasions. The group with implants in both jaws was significantly different from the other two groups in relation to higher incidence of fracture of the teeth and gold-alloy framework. Conclusion: The maintenance requirements of implant-supported fixed prostheses with cantilever arms opposed by fixed prostheses of similar design were much greater than when opposed by natural teeth or complete dentures.