International multidisciplinary expert consensus on the clinical application of patient-specific subperiosteal implants: a modified Delphi study

PURPOSE: To establish international multidisciplinary expert consensus on the clinical application of patient-specific subperiosteal implants across indications, surgical workflow, prosthetic rehabilitation, outcomes and complications, and follow-up and maintenance. METHODS: A modified two-round web-based Delphi study was conducted in accordance with established methodological guidance and ACCORD. Evidence-informed preliminary statements were developed by a multidisciplinary core group. International experts rated each statement on a five-point Likert scale and could provide comments. Consensus was defined as ≥ 75% agreement. Non-consensus or substantively revised statements were redistributed in Round 2. RESULTS: Of 58 invited experts, 23 participated in Round 1 (39.7% response); 22 returned for Round 2 (95.7% retention), with 21 providing valid statement-level ratings. In Round 1, 30 of 43 statements (69.8%) achieved consensus. Round 2 evaluated 15 revised statements (13 non-consensus and two substantively refined), of which 12 (80.0%) achieved consensus. The final set comprised 40 consensus statements across five domains. Agreement was strongest for surgical workflow and follow-up and maintenance, whereas uncertainty persisted regarding indications and outcomes and complications. No consensus was reached on previous head and neck radiotherapy, locking screw fixation systems, or the frequency of mechanical complications. CONCLUSIONS: This study provides an evidence-informed multidisciplinary framework for the clinical use of patient-specific subperiosteal implants. It supports careful patient selection, digitally integrated and prosthetically driven planning, individualized rehabilitation, and structured long-term follow-up, while identifying priorities for further clinical research.