An assessment of fluoride varnish (Duraphat) effectiveness in preventing and keeping under control white spot lesions (WSLs) during fixed orthodontic treatment: a controlled randomized trial

This study examined the impact of fluoride varnish (FD) - Duraphat in 17 patients treated with fixed orthodontic appliances by using a controlled, randomized with two parallel arms design. The 6-month treatment consisted of 9 people in the test group, 8 in the control group, and the application of a single dose of varnish. WSLs in 273 teeth were examined in two different times: before bonding (T0) and 6 month after bonding (T1). Fluorescence Method was combined with Visual Inspection Method. Durr Dental’s VistaCam intraoral fluorescent digital camera produced fluorescent and digital intraoral images which were scored based on Vista Cam and Gorelick scales. WSLs data were analyzed with nonparametric statistical techniques. Three statistical analyses were conducted to test the hypotheses of this study. Mann-Whitney U Test examined the hypothesis about the influence of the FV on WSLs. It analyzed the differences in WSL’s between groups in two different times, before treatment (T0) and after treatment (T1). The difference in WSLs between two groups before treatment was not significant whereas after treatment it was significant. The test group had a WSLs level significantly lower (by 7.6%, or 9.5 times lower) than the control group. Analysis confirmed the hypothesis that patients with fixed orthodontic appliances when treated with FV cope better with WSLs than patients who are not treated with FV. Wilcoxon–Signed Rank Test examined the hypothesis about the effectiveness of FV on preventing or keeping WSLs level under control. It analyzed the change in WSLs level in each group from T0 to T1. Based on the change in WSLs level observed in each group, analysis showed that the effectiveness of FV was either “moderate” (test group) or “high” (control group). The hypothesis, however, was confirmed by data measured by Visual Method and scored by Gorelick scale but not when measured by Fluorescence Method and scored by VistaCam scale. Kruskal-Wallis Test and a Post Hoc Test examined the hypothesis about the relationship between FV effectiveness and teeth function/position. In test group, it analyzed the differences in WSLs level among six teeth subgroups - upper incisors, lower incisors, upper canine, lower canine, upper premolars, and lower premolars. Analysis showed there were no significant differences in WSLs level at the end of treatment among groups [Chi- square=9.118, df=5, Asymp. Sig.=0.104]. The analysis did not confirm the hypothesis laid out in this study. Instead, it concludes that teeth function/position does not affect the degree of effectiveness of FV on preventing or keeping WSLs level under control.