Remineralization Effects of Fluoride Varnish According to Application Protocols: A Systematic Review

Objective: Fluoride varnish represents one of the most effective strategies for preventing dental caries and managing early lesions.This systematic review aimed to evaluate the remineralization effects based on the application protocols.Methods: A systematic literature review was conducted in accordance with PRISMA guidelines.Studies published between January 2021 and December 2024 were searched on seven databases using the search terms "fluoride varnish," "remineralization," "application protocol," and "dental caries prevention."Cochrane ROB 2, AMSTAR 2, and Faggion's 14-item checklist were used for assessing quality.A total of 150 articles were initially identified, among which 29 studies were included in the final analysis after the screening process.Results: The selected studies included 11 in vitro studies, 7 randomized controlled trials, 9 systematic reviews, 1 in situ study, and 1 cohort study.The highest efficacy was demonstrated by 5% sodium fluoride (22,600 ppm), which was most commonly used.While application of fluoride varnish at 6-month intervals with 24-month follow-up resulted in 28.3% caries prevention effect in first permanent molars, 3-month intervals proved more effective and three initial intensive applications followed by regular maintenance yielded optimal results.Combination therapies demonstrated synergistic effects: 5% NaF combined with CPP-ACP and 5% NaF combined with fluoride toothpaste were more effective than 5% NaF alone, while 5% NaF combined with AgNP showed greater effects than AgNP alone.Fluoride varnish demonstrated 63.6% remineralization of enamel caries and reduced white spot lesions by over 50% in orthodontic patients. Conclusion:Fluoride varnish is an effective evidence-based intervention for caries prevention and remineralization.The optimal protocol recommended for high-risk patients involves the application of 5% NaF 2-4 times annually, at 3-month intervals.Additionally, combination therapies yield significantly improved therapeutic outcomes.