Shear bond strengths of brackets bonded with a new self-adhering resin composite

Purpose: To determine the shear bond strength (SBS) of orthodontic brackets bonded with a self-adhering resin composite. Methods: 45 freshly extracted mandibular incisors were randomly divided into 3 groups (n = 15 per group). Brackets were bonded with 3 bonding systems and cured with an LED light. Brackets were bonded with a new self-adhering resin cement in the study group. A conventional etch-and-rinse adhesive system and a self-etching adhesive system were used for comparison. After bonding, the SBS of the brackets were tested with a universal testing machine. Results: Analysis of variance indicated a significant difference between groups (p<0.001). The highest values for SBS were measured in group I (21.80 +/- 2.57 MPa). The SBS was significantly lower in groups II and III than in group I (P<.001). The lowest values for SBS were measured in group III (5.90 +/- 0.90 MPa). SBS was significantly higher in group II than in group III (p<0.001). Conclusions: The self-adhering adhesive system showed a clinically insufficient SBS, whereas the SBS of conventional etch-and-rinse adhesive system and the self-etching adhesive system were significantly higher and clinically sufficient.