Effect of dentifrice of varying fluoride concentration on surface microhardness of fluorosed enamel: an in vitro study

Aim: To evaluate the effect of dentifrice with varying concentrations of fluoride on surface microhardness of fluorosed enamel as compared to a non-fluoridated dentifrice. Study design: In vitro, comparative type. Method: 60 enamel blocks with score-3 enamel fluorosis were randomly divided into three groups: Group I non-fluoridated dentifrice, Group II 1000-ppm fluoridated dentifrice and Group III 1400-ppm fluoridated dentifrice. After evaluating the baseline surface microhardness, samples from each group were brushed for 2 min, twice daily for a period of 21 days with 0.02 g of respective interventional agents as per protocol. Microhardness of the samples was re-evaluated at the end of 21 days. Statistical analysis was performed using paired t test, ANOVA and Kruskal–Wallis test. Results: The surface microhardness within the group from the baseline to 21st day post intervention, showed a statistically significant increase in all three groups, hence indicating that all the three interventional agents used were effective against the fluorosed enamel surface. Intergroup comparison of the surface microhardness of fluorosed enamel from baseline to 21st day post intervention showed a statistically significant difference (p < 0.001) amongst the groups with Group III proving most effective followed by Group I and Group II. Conclusion: 1400-ppm fluoridated dentifrice is more effective as compared to 1000-ppm fluoridated dentifrice and non-fluoridated dentifrice in increasing the surface microhardness of fluorosed enamel. © 2016, European Academy of Paediatric Dentistry.