Fluoride Varnish Efficacy On First Permanent Molars Caries Prevention

To evaluate the two-year efficacy of fluoride varnish (FV) in preventing caries on first permanent molars among children. A longitudinal study included 3,077 first-grade students (7-9 years) in Beijing, China. Participants were divided into intervention (n=1,135; semi-annual FV application) and control (n=1,942; no FV) groups. Caries status was assessed at baseline (2022) and follow-ups (2023, 2024) using WHO criteria. Generalized Estimating Equations (GEE) analyzed longitudinal data, adjusting for age and gender. Overall caries incidence increased with age (5.29% to 16.92% in FV group; 5.56% to 17.10% in controls), with no significant intergroup difference (p>0.05). However, FV significantly reduced caries on specific surfaces: maxillary mesiobuccal (OR=0.268, p<0.001), mandibular mesiolingual (OR=0.187, p<0.001), and right maxillary palatal grooves (OR=0.161, p<0.001). Females exhibited higher caries rates than males (p<0.05). Semi-annual FV application demonstrated localized efficacy on smooth surfaces of first permanent molars, suggesting its targeted use in caries prevention programs. Gender-specific preventive strategies are warranted.