Overview
Fluoride varnish (FV) is resin-based product that contains 2.26% fluoride (22,600 ppm F) from 5% sodium fluoride (NaF) in an alcoholic solution of natural tree resin. The FV adheres strongly to teeth, allowing a prolonged fluoride contact and interaction with hard tissues of teeth over time [1]. Fluoride is slowly released and helps to prevent mineral loss from teeth and enhances remineralisation, to reverse or slow down progression of early carious lesions.
Use and Application
FV treatments are carried out by a dental professional after thorough cleaning and drying. The varnish is topically applied with a small brush, probe or applicator in a thin layer on high risk tooth surfaces, such as occlusal fissures, between teeth (proximal surfaces) or exposed root surfaces. FV can also be applied directly on early caries lesions to arrest or re-mineralize the surface. The varnish should dry and set for one minute. Patients should be instructed to avoid eating, drinking and tooth cleaning for a few hours after application. Moderate-risk patients should receive FV at 6-month intervals whereas high-risk groups should get FV applied at 3-month intervals [2].
Effectiveness and Efficacy
A Cochrane systematic review has shown that FV provides caries protection at 43% in young permanent teeth and 37% in primary teeth [3]. There is evidence showing that FV is effective for arresting or reversing non-cavitated lesions and it may reverse root caries in the elderly [4, 5].
Safety
FV is the only high-fluoride product that is suitable for children under 6 years. The average amount of FV used in one application for a child is around 0.3-0.5 mL, which will deliver around 6.8-11.3 mg F in the oral cavity. This dose is far below the probably toxic dose.
Cost Effectiveness
The cost of FV varies widely between providers and suppliers. The costs for FV programs have been reported to be lower than fissure sealants programs. FV applied in the clinical setting is unlikely to be cost-effective in low-risk populations but clearly more favourable in medium and high-risk patients.
Recommendations
FV for prevention and non-restorative management of caries lesions is endorsed by the WHO and many professional organisations worldwide [2,4]. Target populations are communities with low socio-economy and low health literacy, high risk individuals and patients with active caries disease. The current recommendations suggest that FV should be topically applied by dental professionals 2-4 times per year. Use of FV is safe and suitable for all age groups.
Key Further Reading
1- Fluoride and Oral Health.
O’Mullane DM, Baez RJ, Jones S, Lennon MA, Petersen PE, Rugg-Gunn AJ, Whelton H, Whitford GM. Fluoride and Oral Health. Community Dent Health. 2016;33:69-99.
2- WHO Global Consultation on Public Health Intervention against Early Childhood Caries
Phantumvanit P, Makino Y, Ogawa H, Rugg-Gunn A, Moynihan P, Petersen PE, Evans W, Feldens CA, Lo E, Khoshnevisan MH, Baez R, Varenne B, Vichayanrat T, Songpaisan Y, Woodward M, Nakornchai S, Ungchusak C. WHO Global Consultation on Public Health Intervention against Early Childhood Caries. Community Dent Oral Epidemiol. 2018;46:280-87.
3- Fluoride varnishes for preventing dental caries in children and adolescents.
Marinho VC, Worthington HV, Walsh T, Clarkson JE. Fluoride varnishes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2013 Jul 11;(7):CD002279.
4- Non-restorative Treatments for Caries: Systematic Review and Network Meta-analysis.
Urquhart O, Tampi MP, Pilcher L, Slayton RL, Araujo MWB, Fontana M, Guzmán-Armstrong S, Nascimento MM, Nový BB, Tinanoff N, Weyant RJ, Wolff MS, Young DA, Zero DT, Brignardello-Petersen R, Banfield L, Parikh A, Joshi G, Carrasco-Labra A. Non-restorative Treatments for Caries: Systematic Review and Network Meta-analysis. J Dent Res. 2019;98:14-26.
5- Prevention of root caries: a literature review of primary and secondary preventive agents.
Gluzman R, Katz RV, Frey BJ, McGowan R. Prevention of root caries: a literature review of primary and secondary preventive agents. Spec Care Dentist. 2013;33:133-40.

Guidance Document
ACFF Members can download the full reference document for Fluoride Varnish.