In vitro assessment of an experimental coat applied over fluoride varnishes.
OBJECTIVE
The time of contact between the product and enamel surface is important in ensuring the efficacy of fluoride varnishes. Thus, some alternatives could avoid fluoride loss to saliva and improve the anticariogenic action of the product. This study evaluated the effect of an experimental coat on the anticariogenic action of fluoride varnishes.


METHODS
Enamel bovine blocks were selected by evaluating surface microhardness and randomized into five groups (n=24): placebo, Duraphat, Duraphat with coat, Duofluorid and Duofluorid with coat. Twelve blocks from each group were used to analyze calcium fluoride (CaF2) formed on enamel after treatment. The other 12 blocks were subjected to pH cycling for 7 days. The varnishes were kept on enamel for 6 h. Next, the percentage change of surface microhardness (%SMHC) and mineral loss (DeltaZ) were calculated. CaF2 retained and fluoride present in the pH-cycled solutions were also measured.


RESULTS
The use of the coat did not decrease %SMHC and DeltaZ, but all fluoride varnishes had better results when compared to the placebo (ANOVA and Kruskal-Wallis, respectively). The values from CaF2 formed were higher compared to the values of CaF2 retained (non-paired t test, p<0.05). There was a trend to decrease the amount of F in the solutions at the end of pH cycling (Kruskal-Wallis, p<0.05).


CONCLUSIONS
Although the experimental coat increased the formation of CaF2 on the enamel surface, it did not significantly improve the anticariogenic action of fluoride varnishes.
Delbem
Alberto Carlos Botazzo
AC
Araçatuba Dental School, São Paulo State University, Araçatuba, SP, Brazil. adelbem@foa.unesp.br
Brighenti
Fernanda Lourenção
FL
Oliveira
Felipe Alberto Lino
FA
Pessan
Juliano Pelin
JP
Buzalaf
Marília Afonso Rabelo
MA
Sassaki
Kikue Takebayashi
KT
D000818:Animals; D002417:Cattle; D003743:Dental Enamel; D005460:Fluorides, Topical; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008422:Materials Testing
D005460:Fluorides, Topical