Clinical Comparison of School-Based Dental Sealant Programme Among Different Caries-Risk School Children: A 5-Year Follow-Up Study

Background: Limited evidence supports the sealant application for children. Aim: To assess the association between dental sealant and caries occurrence on first permanent molars among children with different caries risks after 5-year follow-up. Design: This ambispective (retrospective-prospective) cohort study retrieved data from dental sealant programmes conducted in 2019 and 2024 in Bangkok. Students who participated in the programme during first grade (P1) in 2019 and sixth grade (P6) in 2024 and had at least one sound first permanent molar at baseline were included and categorised based on the number of untreated carious teeth in P1: high-risk (> 2 teeth), moderate-risk (1–2 teeth) and low-risk (no carious teeth). Logistic regression analyses were used to compare caries occurrence between students with at least one sealed first permanent molar and those without for each caries risk group. Results: Six-hundred-ninety-five students with 2198 sound first permanent molars were analysed. Sealants did not show a significant caries-preventive effect in low-and-moderate-caries-risk groups. The high-risk group, those with at least one sealed tooth, had a significantly lower risk of developing caries (adjusted OR = 0.48; 95% CI: 0.29–0.80; p = 0.005). Conclusion: Dental sealants are significantly associated with lower caries occurrence, particularly in high-risk children.