The effects of composite resin types and debonding pliers on the amount of adhesive remnants and enamel damages: a stereomicroscopic evaluation

This in vitro study was designed to evaluate the effect of composite resin types and orthodontic debonding pliers on the amount of adhesive remnants and enamel damages using a novel method of measurement. 120 extracted human premolars were randomly divided into four groups (n = 30). The standard edgewise metallic brackets were bonded to the teeth with light-cured composite resin “Transbond XT” in the first and second groups, and No-mix composite resin “Unite” in the third and fourth groups. Bracket debonding was carried out with Lift Off Debonding Instrument “LODI” (3M Unitek) in the first and third groups, and with Bracket Removing Pliers (Dentaurum) in the second and forth groups. yStereomicroscopic evaluation was performed by unbiased sterelogy. All teeth were evaluated for the amount of adhesive remnants and the number and length of enamel cracks. The obtained data on each step was analyzed by two-way ANOVA, chi-square, Wilcoxon, and Kruskal-Wallis. Teeth in group 4 had the lowest adhesive remnants on the enamel surface (p < 0.01); and the highest increase in the number of enamel cracks (p < 0.01) among the groups. In addition, groups bonded with Unite showed the highest increase in the length of enamel cracks. Dentaurum debonding pliers with sheer–peel force, when used with the Unite adhesive (group 4), decreased the amount of adhesive remnants on the enamel surface while it increased enamel damages.