EVALUATION OF THE SHEAR BOND STRENGTH OF DIFFERENT CERAMIC BRACKET BASE DESIGNS

The purpose of this study was to compare the Ceramaflex bracket with a traditional ceramic orthodontic bracket with regard to shear bond str ength and bond failure location. Forty newly extracted human premolars were randomly divided into two groups. Twenty Ceramaflex brackets (TP Orthodontics Inc, LaPorte, Ind) and 20 Transcend 6000 brackets (Unite k Corp, Monrovia, Calif) were bonded to the teeth using the same bondi ng system (Right On, TP Orthodontics Inc, LaPorte, Ind). A Zwick Unive rsal Test machine (Zwick Gm bH & Co, Ulm, Germany) was used to determi ne the shear bond strength for each bracket. After debonding, the teet h and brackets were examined under 10x magnification. After debonding, the amount of resin material adhering to the enamel surface was asses sed according to the Adhesive Remnant Index (ARI).(15) The results of this study suggest that Ceramaflex brackets have a significantly lower bond strength than traditional ceramic brackets. On the other hand, t he bond failure location of the Ceramaflex bracket was consistently mo re favorable, i.e., occurring at the ceramic bracket-polycarbonate bas e.