Shear bond strength of orthodontic brackets treated with Sebond

Previous studies have shown that due to poor adhesion between bonding resins and stainless steel orthodontic brackets, this interface remains a weak link in clinical orthodontic practice. A paste-like substance, Sebond, has been developed in order to strengthen the weak link between metal and resin. The present study was carried out to determine the effect on the shear bond strength, of pretreating the bracket base with Sebond. Two composite resins, Concise Orthodontic Bonding System and Nimetic-Grip were tested, using 40 orthodontic brackets for each resin; 20 brackets were pretreated with Sebond and the remaining 20 acted as controls. Of the Sebond brackets 10 were sandblasted prior to Sebond application. The bonded brackets were stored in water at 37 degrees C for 14 days after which they were tested to failure in the shear mode. Analysis of the results, using a general linear models analysis, showed that pretreating the brackets with Sebond significantly reduced shear bond strength (P < 0.001).