Comparison of the shear bond strength of a so-called ‘dual-cured glass-ionomer cement’ and a conventional resin composite used in orthodontic bonding

Glass-ionomer cements are a promising bonding alternative to resin composite in that they maintain the integrity of the enamel, are easier to debond and prevent enamel decalcification adjacent to the bonded bracket.

The purpose of the study was to compare the shear bond strength of a so-called ‘dual-cured glass-ionomer cement’ (Band-Lok) with a conventional resin composite (Right-On) in bonding orthodontic brackets to enamel. The results indicated that: (1) the resin composite had a significantly greater mean shear bond strength than Band-Lok; (2) the mean shear bond strength of Band-Lok was lower at seven days than at 60 minutes; (3) there was no significant difference between the mean shear bond strength of Band-Lok with and without light curing; (4) all the Band-Lok specimens failed at the adhesive/enamel interface; and (5) Band-Lok does not fit the definition of a glass-ionomer cement. This study did not support the use of Band-Lok as an orthodontic bracket bonding agent; further development is needed to improve its bond strength to enamel.