Fluoride concentration in whole saliva and separate gland secretions after topical treatment with three different fluoride varnishes

Fluoride concentration in whole saliva and in separate gland secretions was determined after a single application of each of 3 different fluoride varnishes with contrasting levels of fluoride in a randomized crossover design. The study group comprised 8 healthy schoolchildren aged 10-12 years treated with A: Bifluorid 12 (6% F); B: Duraphat (2.26% F); and C: Fluor Protector (0.1% F). Unstimulated and stimulated whole saliva, as well as stimulated parotid and submandibular-sublingual saliva, were collected at baseline and 1, 6, 12, and 24h after the varnish treatments. The fluoride concentrations were determined with an ion-selective electrode. Time- and dose-dependent concentration curves were obtained in all the collected secretions, A > B > C. In whole saliva, the fluoride levels were significantly elevated (P<0.01) 1 h after the A and B varnish applications compared with baseline, while the increase was insignificant for varnish C. Similar patterns were unveiled in the parotid and submandibular-sublingual secretions, although the increase in fluoride concentration was modest. The elevated levels did not exceed 6 h for any of the varnish tested. The results of this study suggest a correlation between the concentration of fluoride of the varnish and fluoride levels obtained in saliva after application.