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

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.

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.

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).

The colour change of enamel surface is affected by the type of adhesive materials and clean-up procedures.