Development of fluoride varnish with sustained fluoride release and biocompatibility

The purpose of this study was to fabricate a biocompatible fluoride varnish with sustained fluoride release, and to compare it with commercial fluoride varnishes. For the experimental fluoride varnish, bis-GMA (BG) or two types of rosin (KR-610: K0, KR-612: K2) were used as bases. Either ethyl acetate or ethanol was added as solvent and 5 wt% NaF was used. 5 mg of experimental F- varnishes and 2 commercial products, Cavity shield (CS) and Flor-opal (FO), were applied on a labial surface of bovine teeth (10 mm × 7 mm). The amount of fluoride release was measured at 1 hr, 2 hrs, 3 hrs, 4 hrs, 8 hrs, 12 hrs, 1 day, 3 days, 5 days, 10 days, 15 days, 20 days and 30 days. MTT test was done with diluted F- varnishes using ethanol. Statistical analysis was done with one-way ANOVA and Duncan multiple range test (α=0.05). BG showed the highest fluoride release at 1 hr (P0.05), while that of K0 was highest at 2 hrs (P0.05). From 1 day to 5 days, experimental fluoride varnishes showed higher fluoride release than the commercial products (P0.05), and there were no significant differences after 5 days (P0.05). For MTT test, K0 and FO showed higher cell viability than other experimental groups (P0.05), with no significant differences with K2 (P0.05). Considering the sustained fluoride release and cell viability of the experimental rosin-based fluoride varnishes compared with commercial products, it will be appropriate for clinical application.