Shear Creep Behavior of an Adhesive Resin System at the Interface Between an Orthodontic Bracket and Enamel

Creeping of a resin-composite-based interface between the enamel and an orthodontic bracket was investigated using two testing setups — tooth-bracket and three-point bending ones. Orthodontic brackets were bonded onto an etched enamel surface using various resin composites. A static load was applied to the bracket-tooth, and the time required to debond it from the tooth surface was recorded. In the three-point bending test, the creep and recovery of the resin composite materials were tested using rectangular test specimens. It was found that the incorporation of continuous glass fibers at the interface between the orthodontic bracket and enamel increased the creeping and debonding time of the brackets