Effect of laser enamel-etching on the bond strength of resin-bonded retainers

In this study, thirty extracted maxillary incisors of comparable sizes were used. The teeth were prepared to receive resin-bonded retainers. Each retainer was constructed with a ring on the palatal surface for bond strength testing. The specimens were divided into two groups. The enamel of the palatal surface of each tooth in the first group was etched using the acid gel etching technique. Laser etching was used in the second group. The etched cast metal retainers of both groups were bonded to the corresponding etched teeth using Nimetic-Grip luting composite. The bonding strength was tested using Instron Testing Machine. From this study, the following conclusions were reached: 1. The results of this study proved that, laser was a successful tool for etching of the enamel surfaces. 2. Comparable results of laser etching and acid etching of the enamel were obtained, as they both gave a satisfactory bond strength to the resin-bonded retainers.