Effect of adhesive application on the shear bond strength using different cementing agents in molar and premolar attachments

Objectives: The purpose of the study was to evaluate the effect of adhesive application on the shear bond strength (SBS) of orthodontic brackets and tubes to acid-etched human enamel when using different cementing agents. Study Design: One hundred and sixty metal attachments (80 tubes and 80 brackets) were bonded to human third molars and premolars that were randomly divided into identical groups of four: Transbond XT (XT); Wave MV Flow (WF); APC Plus System (APC); and Fuji Ortho LC (LC). For each experimental group, half of the specimens were bonded in combination with Transbond XT adhesive. After 72 h, a SBS test was performed using a universal testing machine. Statistical analysis was performed using ANOVA with Bonferroni post hoc comparisons, χ2 tests, and linear regression modeling. Adhesive remnant index scores were determined for the teeth after failure. Representative tooth surfaces from each subgroup were assessed under SEM. Results: Considering that each cement was observed, each of them showed similar SBS when the adhesive system was applied as when the adhesive was not applied. By comparing all cements together, it was noted that if an adhesive is not applied, all cements have similar values. If an adhesive is applied, cement XT, WF, and APC showed significantly higher SBS values than LC did. The tubes showed higher SBS than the brackets did in cements XT and WF with or without an adhesive, as well as APC Plus with an adhesive. Conclusions: The use of an adhesive system in bonding brackets and tubes does not influence the SBS obtained, independently of the cement.