Fluoride release and re-uptake of dental materials with fluoride varnish/gel

Fluoride release and re-uptake of dental materials with fluoride varnish/gel

Objectives: This study aimed to compare the amounts of fluoride released by esthetic restorative materials into deionized water and to assess the differences in fluoride re-uptake among esthetic restorative materials, following a treatment of APF-gel and fluoride-varnish. Methods:The each amounts of fluoride release from four materials including a flowable resin (GC), a compomer (3M ESPE) and two glass-ionomers (Fuji II-LC and Fuji IX GP Fast, GC) was measured using an ion-selective electrode and analyzer(37℃, 45d). Composite-resin (Z350, 3M ESPE) was used as a control. After fluoride was released completely, the specimens were treated with the fluoride-gel (APF 1.23%, ANB Inc.) and fluoride-varnish (Fluor protector, Ivoclar Vivadent). The amounts of fluoride release was measured continuatively(37℃, 28d) and the surface roughness was observed under scanning electron microscope. Results: The amounts of released fluoride was under 1ppm in flow resin, 1-2ppm in compomer and 2-8ppm in glass ionomers for 38days. All materials showed negligible levels of release after 45days. After exposure to fluoride varnish/gel, all materials were recharged and continued releasing fluoride. The fluoride was released 0.6-0.2ppm in fluoride-varnish and 0.6-2.6ppm in APF-gel within the first day after application (ANOVA, Dunnett's t-test, p<0.05). The surface of specimens exposed to fluoride-varnish were smoother than others. Conclusion: We conclude that glass ionomers can act as rechargeable slow fluoride release systems and fluoride-varnish applications with glass ionomers could be recommended as a preventive tool especially in caries active children.