Evaluation of fluoride release from experimental TiF4 and NaF varnishes in vitro

Fluoride varnishes play an important role in the prevention of dental caries,promoting the inhibition of demineralization and the increase ofremineralization.

Objective

This study aimed to analyze the amount of fluoride released into water andartificial saliva from experimental TiF₄ and NaF varnishes, withdifferent concentrations, for 12 h.

Material and Methods

Fluoride varnishes were applied on acrylic blocks and then immersed in 10 ml ofdeionized water and artificial saliva in polystyrene bottles. The acrylic blockswere divided in seven groups (n=10): 1.55% TiF₄ varnish (0.95% F, pH1.0); 3.10% TiF₄ varnish (1.90% F, pH 1.0); 3.10% and 4% TiF₄varnish (2.45% F, pH 1.0); 2.10% NaF varnish (0.95% F, pH 5.0); 4.20% NaFvarnish (1.90% F, pH 5.0); 5.42% NaF varnish (2.45% F, pH 5.0) and control (notreatment, n=5). The fluoride release was analyzed after 1/2, 1, 3, 6, 9 and 12 hof exposure. The analysis was performed using an ion-specific electrode coupled toa potentiometer. Two-way ANOVA and Bonferroni''s test were applied for thestatistical analysis (p<0.05).

Results

TiF₄ varnishes released larger amounts of fluoride than NaF varnishesduring the first 1/2 h, regardless of their concentration; 4% TiF₄varnish released more fluoride than NaF varnishes for the first 6 h. The peak offluoride release occurred at 3 h. There was a better dose-response relationshipamong the varnishes exposed to water than to artificial saliva.

Conclusions

The 3.10% and 4% TiF₄ -based varnishes have greater ability to releasefluoride into water and artificial saliva compared to NaF varnish; however, morestudies must be conducted to elucidate the mechanism of action of TiF₄varnish on tooth surface.