Restorations performance after selective caries removal to soft dentine: 18-month follow-up of a controlled clinical trial

This randomized controlled clinical trial aimed to evaluate the clinical performance of composite resin restorations placed after selective caries removal to soft dentin (SCRSD) or stepwise excavation (SW) over an 18-month period. Inclusion criteria were patients with permanent molars and/or premolars presenting deep caries lesions (≥50% of the dentin thickness). Teeth were submitted to SCRSD (n=76) or SW (n=76). Evaluations were performed based on FDI (World Dental Federation) criterion. Survival analysis was performed to estimate the survival of restorations and its association with clinical variables and socio-demographic characteristics (adjusted Weibull regression model). The study was registered on Registro Brasileiro de Ensaios Clínicos (ReBEC 65ntbc). The follow-up period ranged from 6 to 18 months (mean±SD 16.3±3.4 months). Patients' ages ranged from 9 to 55 years (mean±SD 29±10.5 years). A total of 135 teeth (SCRSD=72; SW=63) from 101 patients were evaluated. There were 4 failures in the SCRSD group (2 loss of restoration in need of replacement and 2 marginal fractures in need of repair) and 2 in the SW group (fracture in need of repair). The association between explanatory variables and restoration failure showed similar success rates for SW (99.4%) and SCRSD (97.9%) (p=0.16). Patients presenting gingivitis (≥20% of sites with gingival bleeding) had 8.50 times more risk for failure than those with <20% of bleeding sites (p=0.03). This study showed that placing a composite resin restoration over soft dentin (after SCRSD) did not affect its clinical performance after 18 months. SCRSD is a feasible treatment option for the management of deep caries lesions in permanent teeth as it preserves tooth vitality and tooth structure without compromising restoration longevity.