Evaluation of short-term fluoride release from fluoride varnishes.

Objective: The aim of this study was to compare the rate of fluoride release from fluoride varnishes over a 48-hour period and ascertain the time at which a plateau occurred. This data provides clinically relevant time points to resume tooth brushing after fluoride varnish application.

Study Design: Four commercially available fluoride varnishes, Premier Enamel ProVarnish (EP), Colgate PreviDent (CP), Omni Vanish (OV) and Omni VanishXT (OVXT) were applied on 40 extracted permanent human teeth. Ten teeth served as controls. The teeth were immersed in artificial saliva. At 1, 2, 4, 8, 12, 24 and 48 hours, the teeth were sequentially transferred to new vials. TISAB III and ion selective electrode was used to measure fluoride release. Statistical tools were used to compare the rates of fluoride release and plateau of fluoride release.

Results: CP, EP and OV showed a plateau of fluoride release after 4 hours. OVXT did not show a significant change in fluoride release at any time point. EP had the highest fluoride release in the first 8 hours.

Conclusions: CP, EP and OV released maximum rate of fluoride release in the first 4 hours whereas OVXT did not have a plateau. The studied varnishes released different concentrations of fluoride despite the fact that they all contained 5% sodium fluoride.