In vitro Fluoride Uptake of Primary Teeth Treated with Different Fluoride Varnishes.

Objective: To compare the fluoride concentration and surface smoothness of primary teeth treated with four different fluoride varnishes. Methods: An in vitro experimental study was conducted with 50 primary teeth, divided into four groups (n = 10 per group). Each group (Group I: MI Varnish, Group II: Embrace Varnish, Group III: Fluor Protector, and Group IV: Duraphat) received consecutive fluoride varnishes. Fluoride concentration was measured at three depths (surface, middle, and deep) using microhardness testing. Data were analyzed using one-way ANOVA, followed by Tukey's post hoc test to assess group differences at each depth (P < 0.05). Results: MI Varnish exhibited the highest fluoride concentrations at all depths, significantly outperforming the other varnishes (P < 0.001). At the surface, MI Varnish exceeded Embrace Varnish by 18.0 AU, Fluor Protector by 29.0 AU, and Duraphat by 14.6 AU. Duraphat had the lowest fluoride concentrations across all depths. Conclusion: MI Varnish demonstrated superior fluoride uptake compared to other fluoride varnishes. Second-generation varnishes, such as MI Varnish and Embrace Varnish, showed enhanced fluoride release and bioavailability, which contributes to their effectiveness in preventing enamel caries.