Efeito dose-resposta de uma formulação de dentifrício com concentração reduzida de fluoreto: estudo in vitro

Abstract

The utilization of dentifrices with low fluorine concentration, for children under 6 years of age, has been suggested to reduce the risks of dental fluorosis. However, in order to have anticariogenic potential, the dentifrice should form loosely-bound fluorine (CaF2) on dental enamel. Considering that the formation of CaF2 is a function inversely related to pH, dentifrices with pH 5.5, with 275, 550 and 1,100 ppm F (NaF/silica) were developed in order to assess dose-response effects. A comparison between those dentifrices, a placebo product and the Crest toothpaste (positive control - standard) was carried out. Furthermore, the bioavailability of dentifrices, in terms of formation of total fluorine (TF), CaF2, and fluorapatite (FA) on human dental enamel, was evaluated. An ion-specific electrode was utilized for the determination of the dosage of fluorine. The results revealed that the dentifrice with 550 ppm F was more effective than both the placebo and the dentifrice with 275 ppm, presenting no difference in relation to the positive control (p > 0.05). A dose-effect correlation was observed as to the CaF2 formed. In conclusion, the modified formulation with 550 ppm F can be considered as effective as the standard dentifrice with 1,100 ppm, and its utilization would be safer with regard to dental fluorosis.

In vitro Evaluation of the Effectiveness of Acidic Fluoride Dentifrices

“…Negri and Cury [2002] also demonstrated that the amount of CaF 2 formed after treatment with an acidic 550-g F/g dentifrice (NaF, pH 5.5) was equivalent to that obtained after use of a commercial 1,100-g F/g dentifrice.…”

Validation of a Cariogenic Biofilm Model to Evaluate the Effect of Fluoride on Enamel and Root Dentine Demineralization

“…The concentrations of 150–1,350 ppm F used in the experiment simulates the dilution 1:3 that occurs in the oral cavity [ 38 ] when toothbrushing with toothpastes of low to high fluoride concentration. Therefore, this model could be used to estimate the anti-caries potential of innovative toothpaste formulations with low fluoride concentration [ 46 ] that could be recommended to control enamel caries in children, and formulations with high fluoride concentrations, that have been suggested to control root caries in elderly people [ 19 , 21 , 22 ]. Furthermore, the model could be used to estimate the anti-caries potential of fluoride on the cervical area in adults and elderly people, where dentine is exposed and enamel and dentine are at the same risk of caries.…”

Fluoreto de cálcio depositado sobre o esmalte dentário após aplicação tópica de flúor profissional e escovação com gel fluorado: estudo clínico

“…Cabe ressaltar que o método empregado determina a extração de uma camada superficial do esmalte 9 ou seja, em tese, foi determinada a concentração na superfície. Análises na profundidade do esmalte são possíveis somente in vitro 15 . Ainda que não significativa essa diferença na concentração de F -depositado na forma de CaF 2 na superfície do esmalte, podemos pressupor que fatores individuais como pressão exercida durante a escovação, número e velocidade dos movimentos e capacidade de eliminar o remanescente pela expectoração, poderiam interferir na menor concentração de F -depositada quando da realização da EGF, uma vez que interfeririam no tempo de contato da solução com o esmalte dentário.…”