Twelve‐month clinical performance of a Quercetin‐containing universal adhesive in non‐carious cervical lesions: A triple‐blind randomized trial

The objective of this study was to assess the 12-month clinical performance of a nano-encapsulated Quercetin-containing universal adhesive applied in non-carious cervical lesions (NCCL). Forty-three participants were included in this split-mouth randomized trial. Eighty-six NCCL restorations were placed by two operators and randomly assigned to Prime&Bond Universal (PBU) or Prime&Bond Universal containing nano-encapsulated Quercetin (PBUQ), both applied in self-etch mode (n = 43). Resin composite was incrementally placed. Clinical evaluations were performed at baseline, 6, and 12 months using the World Dental Federation (FDI) and US Public Health Service (USPHS) criteria. Data were analyzed using Friedman repeated-measures and Kaplan-Meier survival analyses. No significant differences were observed at any period between FDIand USPHS clinical criteria. Retention rates were 97.70% (95% CI: 87.9-99.5) for the PBU group and 100% (95% CI: 91.8-100) for the PBUQ group. One restoration failed due to loss of retention in the PBU group. Minor marginal staining was detected in six restorations (PBU = 3; PBUQ = 3), and minimal marginal adaptation discrepancies were observed in four restorations (PBU = 2; PBUQ = 2). In conclusion, modifications of universal adhesives with nano-encapsulated Quercetin may be explored without compromising early clinical performance, supporting further development of bioactive adhesive systems and long-term relevance.