The effectiveness of a fluoride varnish in preventing the development of white spot lesions.

A prospective examination of 10 consecutively treated orthodontic patients was undertaken to examine the effectiveness of fluoride varnish in reducing enamel demineralization. Pairs of dental quadrants for each patient's mouth (ie, maxillary right and mandibular left; maxillary left and mandibular right) were randomly assigned to an experimental or control group. After placement of resin-bonded orthodontic brackets, fluoride varnish was applied to the 2 experimental dental quadrants for each patient. Subsequent applications were done every 3 months during 12 months of orthodontic treatment. A double-blinded examination of intraoral photographs of the 100 experimental and 100 control teeth was done. The presence of white spot lesions was registered using the enamel decalcification index and the 2 groups were compared using paired Student t tests with a significance level of 5% (P < .05). There was no statistically significant difference between the mean enamel decalcification index for the control and experimental groups before or after treatment, since demineralization increased for both groups. Most importantly, the change in mean enamel decalcification index was significantly smaller for the experimental group (0.34), compared to the control group (0.51). In other words, there was 44.3% (P <.05) less demineralization noted for teeth that had been treated with fluoride varnish during orthodontic treatment.