Effects Of Fluoride-releasing Dental Materials On Bovine Enamel Erosion

Objectives: To discuss characteristics of fluoride-releasing materials' effects on remineralization. Materials and Methods: 25 bovine teeth were cut into specimens with 10 mm diameter and 4mm height. Each specimen was coated with nail varnish, only leaving four enamel windows. Specimens were placed into the demineralizing solution (0.1mol/L lactic acid and 6% Carboxy methyl cellurose) in incubator at 37℃, 5% CO 2 for 48h. They were divided into 5 groups, and then each group was treated by ClinproTM XT varnish (CV), F-varnish (FV)，Shield Force (SF), Fuji Ⅲ LC® light-cured glass ionomer pit & fissure sealant (FJ), and Base cement® Glass polyalkenoate cement (BC). The enamel of three windows was remineralized respectively for 2, 4, or 6 weeks in the incubator at 37℃, 5% CO2. Following the 6-week test period, the nail varnish was removed. The results were evaluated by ΔQ values using Quantitative Light-induced Fluorescence and compared based on the remineralization time in each material. Statistical analyses were performed by one-way ANOVA test and Tukey's HSD. Results: Specimens in all the treatment groups except for the SF group increased in ΔQ values with remineralization time. The reduction rate of mean ΔQ values in the legions of the FV group was significantly higher than those of CV and FJ groups after 2-weeks remineralization (P<0.05). And the reduction rate in the BC group was significantly higher than those in the other groups after 4-weeks remineralization (P<0.05). After 6-weeks remineralization, the reduction rate in FV group was significantly lower than those in the other groups (P<0.05), and there was no significant difference in the other three groups (P<0.05). Discussions and Conclusions: Remineralization efficacy of the dental materials depends mainly on the content of fluoride, calcium, and phosphate, and on the pattern of their release.