Clinical Performance and Survival of Adhesive Attachments for Removable Partial Dentures: A Systematic Review

Objectives: This systematic review evaluated the clinical performance and survival of adhesive attachments used as retention elements for removable partial dentures (RPDs) and analyzed associated biological and technical complications. Methods: A systematic electronic search was conducted in PubMed, the Cochrane Library, and Embase in August 2025. Eligible studies included randomized controlled trials, prospective or retrospective clinical studies, and case series with at least 10 patients and a minimum 6-month follow-up. The primary outcome was attachment survival; secondary outcomes included biological and technical complications. Two reviewers independently performed screening, data extraction, and risk of bias assessment using the Newcastle-Ottawa Scale. Due to high heterogeneity, results were analyzed descriptively. This review was prospectively registered (PROSPERO registration number CRD420251116027) and conducted in accordance with PRISMA guidelines. Results: Of 5514 records identified, five longitudinal clinical studies fulfilled the inclusion criteria. Sample sizes ranged from 10 to 123 patients, with follow-up periods between 3 and 270 months. Reported attachment survival ranged from 96% at one year to 61% at 15 years. Technical complications, mainly debonding, occurred in 9% to 18.5% of cases, while biological complications such as caries or abutment fractures were infrequent. All studies were rated as poor-quality owing to missing control groups and incomplete outcome reporting. Conclusions: Within the limitations of the available evidence, adhesive attachments represent a potential option as an invisible retention element for removable prostheses. However, the available findings are based on a limited number of studies with methodological limitations and therefore represent low-certainty evidence. While some studies suggest favorable short-term performance, long-term survival appears to be limited. Debonding was the most frequently reported technical complication, highlighting the technique sensitivity of adhesive cementation. Further well-designed comparative clinical studies with larger sample sizes are required to better clarify their long-term efficacy and clinical indications within removable prosthodontics.