Shear bond strength of metal brackets compared with a new ceramic bracket

One hundred twenty bovine teeth were bonded with two types of metal brackets and a new ceramic bracket for comparison. Two different adhesives were used, a so-called no-mix and a paste/paste adhesive. The shear bond strength of the ceramic bracket was found to be superior for both adhesives. Bond failure with the ceramic bracket occurred predominantly in the enamel/adhesive interface; the failure site for the metal bracket was mainly in the bracket/adhesive interface. It is concluded that the bond strength between the ceramic bracket and the adhesive in shear mode is stronger than that between the adhesive and the enamel.