Effectiveness of pre-treatment with chlorhexidine in restoration retention: A 36-month follow-up randomized clinical trial

Abstract Objectives This study evaluated the effect of the pre-treatment with 2% chlorhexidine digluconate (CHX) as coadjutant in restoration retention of noncarious cervical lesions (NCCL), after 36 months of follow-up. Methods A randomized controlled split-mouth and triple-blind (operators, patients and evaluator) trial was carried out. Patients ( n = 42) with at least two non-carious cervical lesions were included. The teeth with NCCL were randomly assigned to two treatment groups: application of 2% CHX (experimental group) or a placebo solution (control group) for 60 s after acid etching and before the adhesive application. A trained and calibrated examiner evaluated the restorations at baseline (1 week) and at each recall (6, 12, 24 and 36 months) using the FDI criteria. A total of 225 restorations were evaluated after 36-month follow-up. Data were subjected to survival analysis using the Kaplan–Meier method, and the log-rank test was used to evaluate the existence of differences between the survival curves ( α = 0.05). Results The restorations survival rate after 36 months of follow-up was 76.1%. There was no difference in the retention and failure rates between the experimental and the control group ( p = 0.968). There was an increased failure trend when restorations were located subgingival compared to those at the gingival level or supragingival. Conclusion The pre-treatment with 2% chlorhexidine digluconate did not promote further restoration retention of noncarious cervical lesions. Clinical significance The cavity pre-treatment with chlorhexidine for inhibition of hybrid layer degradation does not add any beneficial effect to the clinical performance of restorations.