Effect of Fluoride Varnish and Solution on Enamel Erosion in vitro

Abstract

The effect of fluoride varnish and solution on initial enamel erosion was studied. Enamel specimens prepared from human third molars were treated for 24 h with Duraphat® varnish (2.26% F) or for 48 h with NaF solution (1.2% F), washed, and immersed in cola beverage (pH 2.6) for up to 15 min. The surface microhardness was measured using a Vickers diamond in a Leitz indentation apparatus at baseline, after fluoride treatment, and after 1, 5, and 15 min exposure to acidic drink. The specimens were then prepared and studied using a JEOL JSM–35 scanning electron microscope. The results showed that both fluoride treatments caused an increase in enamel hardness values and subsequent inhibition of softening which was statistically highly significant. Scanning electron micrographs revealed the difficulty of removing Duraphat varnish from the enamel surface, and remnants of varnish were seen irrespective of vigorous sonication in acetone. However, in areas devoid of varnish, erosion was observed as mainly irregular lesions similar to those seen in the NaF solution treated and control specimens. The present study showed that treatment of enamel with topical fluoride prior to acidic challenge can inhibit initial erosion.

Protective effect of calcium nanophosphate and CPP-ACP agents on enamel erosion

“…Figure 2B shows a rough and eroded surface with no formation of a protective layer for the varnish group, visualized as a honeycomb-like demineralized enamel structure (Figure 2A). In some studies, which showed the protective effect of fluoride varnish against dental erosion, 21 the varnishes were not completely removed during the experimental period, and this mechanical protection may have played a role in the protective effect evidenced. Apart from fluoride, the CPP-ACP complex showed an increase in enamel microhardness and a decrease in enamel surface roughness after erosion by cola drinks.…”

Susceptibility of Enamel Treated with Bleaching Agents to Mineral Loss After Cariogenic Challenge

“…Topically applied fluoride may reduce the solubility of the surface enamel, render the tooth surface harder, more resistant to demineralization, and more prone to remineralization (Skartveit et al, 1990). The inhibiting effect of sodium fluoride on caries is well documented and a protective effect against dental erosion has been shown in vitro (Sorvari et al, 1994;Ganss et al, 2001). Fluoride varnishes provide long contact periods between the dental tissues and the fluoride agent resulting in high fluoride uptake and the formation of calcium fluoride deposits that act as fluoride reservoirs (Arends J & Schuthof, 1975;Grobler et al,1983;de Bruyn,1987;Petersson,1993).…”

Prevention. Part 3: Prevention of tooth wear

“…Topical fluoride appears to protect against this subsequent tooth wear following acid challenge. [35][36][37] This is especially helpful in reducing dentine wear in previously eroded teeth. 38 Fluoride, therefore, appears to have only a limited protective effect against erosive challenge in vivo (Type 4).…”