Effects of different orthodontic primers on enamel demineralization around orthodontic brackets

Aim The purpose of this work is to evaluate the effectiveness of one self-etching and two filled orthodontic primers on enamel demineralization around orthodontic brackets. Methods Brackets were bonded to 84 bovine teeth and the vestibular enamel surfaces covered with acid-resistant nail varnish exposing 1 mm of space on each side of the bracket base. The teeth were allocated to four groups, using either Transbond™ XT conventional primer on etched enamel (group 1), Transbond™ Plus Self-Etching Primer on untreated enamel (group 2), Pro Seal® filled resin primer on etched enamel (group 3), or Opal Seal® filled resin primer on etched enamel (group 4). Each tooth was subjected to 15,000 strokes of brushing followed by exposure to an acid challenge. Calcium-ion release from each sample was calculated using atomic absorption spectrophotometry. Data were analyzed using one-way ANOVA and a post hoc Tukey test. Differences were considered statistically significant at p ≤ 0.05. Results Statistically significant differences were observed between the four groups (p < 0.001). No significant difference was found between the controls (group 1) and the Opal Seal® group. Higher calcium release was observed in the Pro Seal® group and the self-etching primer group compared to the controls. The highest calcium release was recorded in the self-etching primer group. Conclusion Filled sealants may not have a protective effect against enamel demineralization. Transbond™ Plus Self-Etching Primer should be used cautiously, considering the risk of demineralization involved in its application.