Dose-Response Effect of Fluoride Dentifrices on De-/Remineralization of Root Dentine in situ

Abstract

The present study aimed to evaluate the effect of fluoride (F) dentifrice with different F concentrations on root dentine de-/remineralization. Ten healthy volunteers took part in this randomized, double-blinded, cross-over, and split-mouth in situ experimental study. During 4 phases of 7 days, they wore a palatal appliance containing 4 bovine dentine blocks (2 sound and 2 with caries) of 4 × 4 × 2 mm. Treatments were performed with silica-based dentifrices containing 0, 700, 1,300, and 5,000 µg F/g (F as NaF). To provide a cariogenic challenge, a 20% sucrose solution was dripped 3 and 8 times daily on the carious-like and sound blocks, respectively. After each experimental phase, the percentage of surface hardness loss (%SHL) or recovery (%SHR) was calculated and the fluoride concentration in the biofilm was determined. The statistical analysis was performed using ANOVA and the Tukey post hoc test with <i>p</i> at 5%. The relationship between variables was analyzed by linear regression. The results showed a lower %SHL when 5,000 µg F/g dentifrice was used but without a statistically significant difference from the conventional one (1,300 µg F/g). Regarding remineralization and F in biofilms, the high-fluoride dentifrice was expressively superior in mineral replacement on the surface and in the F concentration in the biofilms, respectively, compared to the other 3 products (<i>p</i> < 0.05). Also, a significant linear fit between mineral loss/gain, F in biofilms, and fluoride concentration in the dentifrices could be observed. In conclusion, a dose-response F effect was observed, and the high-fluoride dentifrice was effective in enhancing root dentine remineralization in this short-term in situ study.

Optimal Surface Pre-Reacted Glass Filler Ratio in a Dental Varnish Effective for Inhibition of Biofilm-Induced Root Dentin Demineralization

“…The root surface is more susceptible to acid demineralization compared to enamel [35,36]. Products with higher fluoride (F) concentrations have been suggested for the protection of the root surface [37,38]. However, fluoride varnish films are not expected to remain longer on the surface but to be quickly removed by brushing and wear.…”

Efficacy of Topical Strategies to Prevent the Onset of Root Caries Lesions, In vitro.

“…Fluoride therapy has been the most effective strategy in preventing dental caries lesions [7,8]. Fluoride-releasing agents are available both as preventive methods and as early non-invasive treatment of caries lesions [9][10][11][12][13][14][15], the evidence supports that the application of a high concentration fluoride (F) is more effective than the use of a standard fluoride toothpaste [9]. Regular tooth brushing with fluoride dentifrices is the most rational way to administer topical F. Toothpaste with 5000 ppm F applied twice daily has been reported to be more effective than dentifrice with 1450 ppm F in stopping root caries lesions in both dependent individuals applied by nursing staff [16], and applied autonomously by patients [9].…”