LAUSR

BACKGROUND Patients with multi-bracketed fixed orthodontic appliances are at a higher risk of developing enamel demineralisation. AIM To compare the efficacy of quarterly application of two varnishes in preventing white spot lesions (WSLs) during multi-bracketed fixed orthodontic treatment. Design Ninety-nine patients were randomly allocated into three intervention groups: Group A- standard oral hygiene instructions (OHI); Group B- 5% Sodium Fluoride (NaF) varnish with standard OHI; and Group C- NaF plus tricalcium-phosphate varnish with standard OHI. The outcome was assessed at 6-monthly intervals using a quantitative laser fluorescence device, clinical evaluation, and photographic evaluation on six maxillary anterior teeth. Logistic regression using generalised estimating equations with the intervention group, time, and their interaction was used to compare the occurrence of WSLs, whereas the Kruskal-Wallis independent-samples test to compare the means of fluorescent values among different groups at p=0.05. RESULTS Generalised estimating equations (with intervention and time as predictors) showed that only the effect of time was found to be significant (p<0.001), whereas there was no significant difference among the three intervention groups (p=0.305) using clinical assessment or photographic assessment (p=0.599). At 18-months follow-up, Sodium Fluoride (NaF) varnish with standard OHI was shown to reduce the odds of WSLs by 55%. (p=0.200) and NaF plus tricalcium-phosphate varnish with standard OHI reduced the odds by 42% (p= 0.327). CONCLUSION The study failed to demonstrate that quarterly application of both the study varnishes with OHI provided additional benefit compared to standard OHI alone in preventing WSLs, taking the effect of time of follow-up into consideration. There were higher odds of developing WSLs with an increased duration of orthodontic treatment.