Effects of cervical restorations on the periodontal tissues: 5-year follow-up results of a randomized clinical trial

Objective: This study evaluated the effect of resin composite restorations of non-carious cervical lesions (NCCLs) on the occurrence/progression of gingival recession (GR), considering different tooth isolation techniques. Methods: A randomized controlled split-mouth and blinded trial was carried out. Patients (n = 38) with at least two NCCLs were included. Before the cervical restoration placement, the NCCLs (181 teeth) were randomly allocated into two treatment groups according to the tooth isolation techniques: cotton roll or rubber dam. Experienced, trained, blinded, and calibrated examiners performed periodontal evaluations at baseline and 5year follow-up, using a periodontal probe. Restorations were assessed with the FDI criteria. Thirty-two patients (154 teeth) were evaluated at 5 years. The occurrence/progression of GR between baseline and follow-up was considered the primary outcome. The relative risk (RR) and 95 % confidence interval (95 %CI) were calculated by Poisson regression (? < 0.05). Results: After 5 year, 31 teeth (13.6 %) presented occurrence/progression of GR. In the multivariate analyses, the occurrence/progression of GR was associated with the use of rubber dam isolation (RR; 95 %CI: 2.65; 1.01?7.00) and a lack of marginal adaptation of the restoration (RR; 95 %CI: 10.98; 2.31?52.30). Toothbrush stiffness, use of abrasive dentifrice, tooth type, and the presence of biofilm or gingivitis did not present a statistically significant higher risk for occurrence/progression of GR. Conclusion: The use of rubber dam isolation associated with retraction clamp and the lack of a proper marginal adaptation of the composite restorations are risk indicators for the occurrence/progression of GR in individuals who received a restoration for an NCCL. Clinical significance: Isolation with a rubber dam and dental clamps may promote GR in sites with restored NCCLs. Moreover, clinical examinations for lack of marginal adaptations of the restorations may be included in a clinical setting.