Six-year clinical evaluation of a copper-containing universal adhesive in non-carious cervical lesions: A split-mouth double-blind randomized clinical trial.

Objectives: To evaluate the clinical performance of a universal adhesive system containing 0.1 % copper nanoparticles (CuNp) in non-carious cervical lesions (NCCLs) after 6 years.
Material and Methods: Two hundred and sixteen restorations (n = 54) were randomly placed in 36 participants with at least four NCCLs. Groups included: ER-Cu (adhesive in etch-and-rinse strategy with CuNp), ER-Ct (etch-and-rinse without CuNp), SE-Cu (self-etch with CuNp), and SE-Ct (self-etch without CuNp). Restorations were evaluated at baseline and after 1, 3, 4, and 6 years using the FDI and USPHS criteria.
Primary Outcome: fracture of material and retention. Examiners and patients were blinded to group assignment.
Results: After 6 years, 104 restorations were analyzed (ER-Cu 24, ER-Ct 29, SE-Cu 27, SE-Ct 24). Fourteen restorations loss retention (ER-Cu 6, ER-Ct 1, SE-Cu 2, SE-Ct 7). Retention rates (95 % confidence interval) were 79.3 % (61.6 - 90.1) for ER-Cu; 97.0 % (83.3 - 99.4) for ER-Ct; 93.1 % (78.1 - 98.1) for SE-Cu; and 76.7 % (59.1 - 88.2) for SE-Ct, with statistical differences between SE-Cu vs. ER-Ct, and SE-Ct vs. ER-Ct (p < 0.05). Thirty-one restorations (ER-Cu 6, ER-Ct 5, SE-Cu 9, SE-Ct 11) showed minor marginal staining, and forty-one restorations (ER-Cu 8, ER-Ct 10, SE-Cu 11, SE-Ct 12) presented minimal marginal adaptation defects (p > 0.05). No significant differences were found for other secondary parameters (p > 0.05).
Conclusion: This is the first 6-year clinical trial showing the long-term behavior of a universal adhesive system in NCCLs. The addition of CuNp does not affect the clinical performance of the universal adhesive.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier Ltd.)