Evaluation of the effect of PVA tape supplemented with 2.26% fluoride on enamel demineralization using microhardness assessment and scanning electron microscopy: In vitro study

ObjectiveThis in vitro study was designed to evaluate the effectiveness of experimental 2.26% fluoride-polyvinyl alcohol (F-PVA) tape in inhibition of enamel demineralization using enamel surface microhardness (SMH) analysis and scanning electron microscopy (SEM) examination.DesignEnamel specimens (n = 60) prepared from bovine incisor teeth with microhardness ranging from 260 to 370 Knoop hardness number (KHN) were pooled and randomly assigned to four groups: control group, F-PVA tape group, F-varnish group, and CPP-ACFP group. After topical application of agents in each group, pH-cycling was processed. Then, SMH was measured and the percentage loss of surface microhardness (%SML) was calculated. For the SEM examination, five sample specimens in each group were treated and the morphologic character was evaluated.ResultsAfter pH-cycling, the SMH values of the enamel specimens of F-PVA tape and F-varnish group were significantly higher than that of CPP-ACFP group, there was no significant difference between F-PVA tape and F-varnish group. With SEM examination, enamel surface in the F-PVA tape group showed mild irregularity in general and numerous spherical and ovoid crystals formed on the enamel surface were also observed. The density of crystals was higher than that of both control group and CPP-ACFP group.ConclusionF-PVA tape is effective in inhibition of enamel demineralization. The inhibition potential of enamel demineralization of F-PVA tape is comparable with that of fluoride varnish and greater than that of CPP-ACFP. With the significant advantages of excellent physical properties, ease of application, and improved safety, F-PVA tape can be used not only for professional treatment, but also in a home-use delivery system.