Effectiveness of school-based dental sealant programs among children from low-income backgrounds in France: a pragmatic randomized clinical trial

Objectives A split-mouth randomized clinical trial was carried out to assess the effectiveness of a school-based dental sealant (SBDS) program for French children from low-income backgrounds. The secondary objectives were to determine the effectiveness of the program according to the baseline individual caries risk (ICR) and to assess the sealant retention. Methods The study included 276 pupils from Nice. The sealing was performed in the first or second grades. The permanent first molars were randomized into two groups: one received resin-based sealant and the other no treatment. Active caries on permanent and temporary teeth, visible plaque, Streptococcus mutans (SM) and Lactobacillus counts were recorded at baseline to assess ICR. An intent-to-treat analysis was performed based on the occurrence of new caries at 1 year of follow-up (study outcome). Univariate and multivariable conditional tooth-matched logistic regression analyses (Proc phreg; SAS) were used to assess the effectiveness of the SBDS program. Results At 1 year of follow-up, 253 children (421 pairs) remained in the analysis. In the adjusted analysis, first permanent molars that received sealants were less at risk of developing new caries at 1 year of follow-up compared with those from the control group (OR = 0.26, 95% CI: 0.14–0.49). Independently of the treatment, SM count, and all other covariates, only the variable ‘active caries at baseline’ remained related to new caries on first molars at 1 year (OR = 3.11, 95% CI: 1.27–7.62). The effect of the sealants was significant only when the analyses included subjects with active caries (OR = 0.25; 95% CI: 0.12–0.50) or with a high SM count (>105, OR = 0.20; 95% CI: 0.10–0.41) at baseline. At the 1-year follow-up, total retention was recorded in 52.7% (n = 222) of the treated teeth. Conclusion The 1-year effectiveness of the SBDS program was demonstrated in low socio-economic areas. Selection of schoolchildren according to individual caries risk factors should be considered in a SBDS program.