Hybrid implant-supported rehabilitation of severely atrophic jaws using custom-made subperiosteal and conventional endosseous implants: A retrospective case series

Severe alveolar bone atrophy represents a major challenge for implant-supported rehabilitation of the maxilla and mandible. While custom-made subperiosteal implants and conventional endosseous implants have each been proposed as graftless solutions in selected clinical scenarios, the outcomes of hybrid rehabilitations combining both implant systems within the same jaw have not yet been investigated. The aim of this retrospective study was to evaluate the clinical and radiological outcomes of hybrid implant-supported rehabilitations using custom-made subperiosteal implants in combination with conventional endosseous implants in patients with severe maxillary and/or mandibular atrophy. Fourteen consecutive patients affected by advanced jaw atrophy and heterogeneous residual bone availability were included. A total of 20 custom-made subperiosteal implants and 48 conventional endosseous implants were placed to support fixed full-arch or segmental prosthetic rehabilitations. Implant survival, success, biological and mechanical complications, and peri-implant soft tissue conditions were assessed over a mean follow-up of 22.1 months. At the last follow-up, survival of both subperiosteal and endosseous implants was 100%, with all rehabilitations remaining functional. All endosseous implants fulfilled established success criteria, while all subperiosteal implants met a composite functional success endpoint. Peri-implant soft tissue conditions remained stable, and no prosthetic complications were observed. However, these findings should be interpreted in light of the retrospective design, limited sample size, and relatively short follow-up. Within the limitations of this retrospective case series, hybrid rehabilitations combining custom-made subperiosteal and conventional endosseous implants may represent a promising and flexible graftless treatment option for severely atrophic jaws with heterogeneous bone availability.