[Comparative study of enamel discoloration related to bonding with different orthodontic adhesives and cleaning-up with different procedures].

PURPOSE: The aim of this study was to compare if there was any difference in the enamel discoloration after staining when three orthodontic adhesives and 4 enamel clean-up methods were tested. METHODS: Three types of orthodontic adhesives were used: chemically cured resin, light-cured resin and resin-modified glass-ionomer cement. A total of 120 human extracted premolars were included. Ten teeth of each orthodontic adhesive were randomly cleaned-up with 1 of 4 different procedures and stained in coffee for 7 days: carbide bur (TC), carbide bur and Sof-Lex polishers (TC＋SL), carbide bur and One Gloss polishers (TC＋OG), carbide bur and PoGo polishers (TC＋PG). Colour measurements were made with Crystaleye dental spectrophotometer at baseline and after storage in a coffee solution for 1 week. Two way ANOVA and Bonferroni test were used for statistical analysis with SPSS 13.0 software package. RESULTS: The colour change values of adhesive materials in the TC group were the greatest. The lowest ΔE* values were obtained from the TC＋SL group. However, there was no significant difference between the TC＋SL and TC＋PG group (P>0.05). The resin-modified glass-ionomer cement group showed the lowest colour differences and chemically cured resin group showed the highest ΔE* values among all orthodontic adhesives (P<0.05). CONCLUSIONS: The colour change of enamel surface is affected by the type of adhesive materials and clean-up procedures.