Effectiveness of Fluoride Varnishes for White Spot Lesion Prevention and Remineralization during Orthodontic Treatment: A Randomized Controlled Trial.

Abstract

This study investigated the effectiveness of titanium tetrafluoride (TiF4) varnish compared to sodium fluoride (NaF) varnish for preventing and remineralizing white spot lesions (WSLs) in individuals undergoing orthodontic treatment. This randomized, placebo-controlled, and double-blinded study was conducted with sixty-five adolescents who were selected based on caries activity and then randomized into three parallel groups: G1 (placebo varnish), G2 (5%-NaF varnish) and G3 (4%-TiF4 varnish). Volunteers received varnish application weekly for the first 4 weeks, after 6 (T1) and 12 (T2) months. The measured outcomes included: prevention of new WSLs, and reversal/progression of WSLs, assessed by Nyvad and ICDAS indices, as well as quantitative light-induced fluorescence (QLF). Chi-square, ANOVA, and Kruskall-Wallis tests were applied. The level of significance was set at 0.05, and post hoc Bonferroni test for p values were performed to correct for multiple comparisons. 1,274 teeth were included; 70.5% were Nyvad 0, and 29.5% were Nyvad 1, with no differences between the groups at baseline (T0). Regarding ICDAS, 70.5% were ICDAS 0, 21.6% were ICDAS 1, and 7.9% were ICDAS 2. G1 showed an increasing prevalence of WSLs at T1 and maintained stable at T2; G2 exhibited a decline at T2, while G3 experienced a decrease at T1 and T2 (p < 0.01). Incidence of WSLs at T2 was 10.2% (G1), 5.6% (G2) and 1.4% (G3). The percentage of teeth initially scored as Nyvad 0 that progressed to Nyvad 1 was 13%, 6.8%, and 1% for G1, G2, and G3, respectively. Conversely, the percentage of teeth initially scored as Nyvad 1 that regressed to Nyvad 0 or Nyvad 2 (T0-T2) was 14%, 49.3%, and 74.4%, respectively (p < 0.001). As for ICDAS index, regression was observed in 6.5%, 17.8% and 24%, while progression was observed in 14.9%, 7.7% and 0.9% for G1, G2 and G3, respectively (p < 0.001). Significant differences among the 3 groups for integrated fluorescence loss (mean±SD, G1: -14.28±9.47, G2: -11.10±11.49 and G3: -6.77±11.00) were found at T2 (p < 0.01). Both varnishes demonstrated the ability to prevent and remineralize WSLs. However, TiF4 varnish exhibited the most effective control over WSLs during the 12-month orthodontic treatment.