Urinary fluoride output in children following the use of a dual-fluoride varnish formulation.
OBJECTIVE
This study evaluated the bioavailability of fluoride after topical application of a dual-fluoride varnish commercially available in Brazil, when compared to Duraphat.


METHODS
The urinary fluoride output was evaluated in seven 5-year-old children after application of the fluoride varnishes, in two different phases. In the first phase (I), children received topical application of the fluoride varnish Duofluorid XII (2.92% fluorine, calcium fluoride + 2.71% fluorine, sodium fluoride, FGM). After 1-month interval (phase II), the same amount (0.2 mL) of the fluoride varnish Duraphat (2.26% fluorine, sodium fluoride, Colgate) was applied. Before each application all the volunteers brushed their teeth with placebo dentifrice for 7 days. Urinary collections were carried out 24 h prior up to 48 h after the applications. Fluoride intake from the diet was also estimated. Fluoride concentration in diet samples and urine was analyzed with the fluoride ion-specific electrode and a miniature calomel reference electrode coupled to a potentiometer. Data were tested by ANOVA and Tukey's post hoc test (p<0.05).


RESULTS
There were significant differences in the urinary fluoride output between phases I and II. The use of Duofluorid XII did not significantly increase the urinary fluoride output, when compared to baseline levels. The application of Duraphat caused a transitory increase in the urinary fluoride output, returning to baseline levels 48 h after its use.


CONCLUSIONS
The tested varnish formulation, which has been shown to be effective in in vitro studies, also can be considered safe.
Olympio
Kelly Polido Kaneshiro
KP
Department of Environmental Health, School of Public Health, University of São Paulo, São Paulo, SP, Brazil.
Cardoso
Vanessa Eid da Silva
VE
Bijella
Maria Fernanda Borro
MF
Pessan
Juliano Pelim
JP
Delbem
Alberto Carlos Botazzo
AC
Buzalaf
Marília Afonso Rabelo
MA
D001682:Biological Availability; D001938:Brazil; D002124:Calcium Fluoride / Q000008:administration & dosage / Q000493:pharmacokinetics; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D002675:Child, Preschool; D004032:Diet; D005260:Female; D005459:Fluorides / Q000652:urine*; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000493:pharmacokinetics*
D002327:Cariostatic Agents; D005460:Fluorides, Topical; C023807:sodium fluoride topical preparation; D012969:Sodium Fluoride; D002124:Calcium Fluoride; D005459:Fluorides