Salivary Fluoride Concentration Following the Application of Three Different 5% NaF Varnishes

Objective: To compare the release of fluoride into unstimulated wholesaliva in vivo after the application of three different 5% NaF varnishes:Enamel Pro, Vanish, and Duraphat.Experimental Methods: Following IRB approval, 15 subjects wererecruited and consented based upon the inclusion/exclusion criteria of thestudy. A four-treatment randomized cross over study design with a 2-weekwashout period between treatments was used. Treatment consisted of theapplication of 0.4 ml of either a 5% NaF varnish, or a placebo (no fluoride)varnish applied to the buccal surfaces of all the teeth. After a minimum of 2weeks washout period, the next randomly assigned treatment was given. Allsubjects received the 4 different treatments and during each treatmentunstimulated whole saliva was obtained at baseline and 1, 4, 6, 26, and 50hours. Following storage, saliva samples were centrifuged and thesupernatant salivary fluoride was measured using a fluoride ion specificelectrode to compare unknown values with a standard curve. Mixed lineareffects models were used to evaluate the effects of varnish and time onsalivary fluoride concentration. Significance was determined at 5% level forall tests.Results: For time periods 1, 4, 6, and 26 hours, treatment with Duraphat andVanish resulted in significantly higher mean concentrations of salivaryfluoride than Enamel Pro, but were not different from each other. 50 hoursafter treatment, mean salivary fluoride levels for Duraphat were greater thanall other treatments. For all the fluoride containing varnishes, the maximumamount of fluoride was measured at the 1 hour time point [D (18.94±9.95),V(19.78±14.57), EP (6.19±4)] and the fluoride concentration decreased ateach time point thereafter. When treated with Enamel Pro and Vanish, meanbaseline salivary fluoride concentrations were reached by 26 hours. Meansalivary fluoride concentrations with Duraphat treatment was still abovebaseline at the 26 hour collection point.Conclusions: Salivary fluoride concentrations after treatment with Duraphatand Vanish are similar over 26 hours. Treatment with Enamel Pro resulted insignificantly less fluoride in saliva over 26 hours. Despite the similarfluoride concentrations, the fluoride release into saliva from these varnishesover time differs. The reasons for this difference warrant furtherinvestigation.