Plaque Fluoride Concentrations in a Community without Water Fluoridation: Effects of Calcium and Use of a Fluoride or Placebo Dentifrice

Abstract

The results of a recent study by Whitford et al. [Caries Res 2002;36:256–265] with subjects whose drinking water was fluoridated led to two major conclusions: (1) Compared to the use of a placebo dentifrice, plaque fluoride concentrations ([F]) throughout much of the day are not significantly increased by the use of an F dentifrice but (2) they are positively related to plaque [Ca] (p = 0.0001). The present double-blind, double-crossover study with 16 subjects used the same protocol and was done to: (1) determine the effects of the use of an F dentifrice on salivary and plaque [F] in a community without water fluoridation and (2) further examine the relationship between plaque [Ca] and [F]. Following the use of an F dentifrice or placebo for one week, whole saliva and plaque were collected 1.0 and 12 h after the last use of the products. The study was repeated to include rinsing with a 20 mmol/l CaCl₂ solution immediately before the use of the dentifrices. The CaCl₂ rinse had only minor effects on salivary [Ca] and [F] and none on the plaque concentrations. Unlike the results found in the fluoridated community, all salivary and plaque [F] associated with the use of the F dentifrice were significantly higher than those associated with the use of the placebo. The results suggest that the cariostatic effectiveness of an F dentifrice should be greater in areas without water fluoridation. As noted previously, plaque [F] were positively related to plaque [Ca] (p = 0.0001).

Fluoride retention in saliva and in dental biofilm after different home-use fluoride treatments

“…This could have resulted in greater fluoride concentrations in saliva and in dental biofilm at 12 h or more after the last use of fluoride products, as compared with a relatively low baseline concentration. 30 The results of this study are in agreement with the findings of most of the studies conducted in areas with a fluoridated water supply. 13,20,21,22 These studies also did not show a long-term effect on the fluoride concentration in saliva and in dental biofilm compared to baseline values.…”

“…7,8,14,15,25,26,30 In these studies, fluoride measurements were taken on saliva samples collected 6-24 h after the regular daily use of fluoride products, brushing with a fluoride dentifrice, and/or using fluoride mouthrinsing. Most of these studies reported that the fluoride concentrations in saliva remained significantly elevated, over a period of 12-24 h, compared with the baseline.…”

“…A possible explanation for these is that plaque-binding sites for long-term fluoride retention are occupied by fluoride ions largely in communities with fluoridated water, but not where the water contains only traces of this ion. 30 However, two studies carried out by the same authors and conducted in an area with a fluoridated water supply yielded contradictory results. 22,24 The results of the study conducted in 2006…”

Heterocontrole da fluoretação da água de abastecimento público em Bauru, SP, Brasil

“…Frequent increments in fluoride levels in the mouth reduce the mineral loss, thus reducing the progression of the caries. 4,10,11 Furthermore, studies 10,11 have shown that, in populations supplied with fluoridated water, the fluoride concentration on the plaque is not significantly increased over a large proportion of the day through the use of fluoridated toothpaste. Although the fluoride concentration on the plaque and in saliva increases abruptly during the use of a fluoridated toothpaste or a fluoridated mouthwash, it declines rapidly thereafter.…”

Effect of a Calcium Prerinse on Salivary Fluoride after a 228-ppm Fluoride Rinse

“…An initial examination indicated that the data were not normally distributed. Thus, in order to normalize the data [Zero et al, 1992a;Vogel et al, 2000;Whitford et al, 2005], a logarithmic transformation of the salivary F levels was used prior to an analysis of variance test of the null hypothesis that there is no difference among the rinses in experiment 1. The Newman-Keuls multiple comparison test was then used on the transformed data to examine the effect of the rinses.…”