To seal or restore occlusal caries in permanent molar teeth, 11-year RCT.

Introduction: Sealing of occlusal dentin caries has shown promise in studies, but long-term outcomes remain inconclusive. This RCT aimed to investigate the potential of postponing restorative interventions of manifest occlusal caries by sealing.

Methods: After randomization (ratio 2:1), 341 resin sealings and 152 composite restorations in 493 patients (6-17 years) were performed by 66 dentists in nine Danish municipalities. All lesions were pre-designated to require restorative treatment by the treating dentists. The treatments were controlled annually both clinically and radiographically. The primary objectives, assessed at different observation intervals, were to analyze the survival of sealing until replacement by restoration, the survival of sealing and restoration until retreatment, caries progression beneath sealing and restoration, and the longevity of repaired versus unrepaired sealing until replacement by restoration. The secondary objectives identified factors influencing survival of sealings and restorations. Chi-square/Kaplan-Meier/Cox-regression were used for statistical analyses.

Results: After 11 years, dropout rate was 10%, and 22% of sealings were repaired/renewed. 58% of sealings and 81% of restorations remained sealed/restored until completion due to age 18 or primary caries. Additionally, 33% of sealings were replaced by restorations, and 12% of restorations were repaired/replaced (p-values<0.001). No endodontics were performed. The mean annual failure rates were 4%-7% for sealings and 1% for restorations. The survival of sealings were affected by various predictor variables across the outcomes and observation intervals. The survival rate of repaired/renewed sealings was comparable to that of new sealings (p=0.96).

Conclusions: This long-term study provided a comprehensive overview regarding reasons and time for retreatments of occlusal sealings and restorations. The results indicate that sealing is an effective treatment for occlusal enamel and dentin caries.