The effect of delayed curing time of a self-etch primer on shear bond strength of the orthodontic bracket

Abstract

This study investigated if a delay in curing time of a self-etching primer (SEP) affects the shear bond strength (SBS) of orthodontic brackets and the Adhesive Remnant Index (ARI) score. In 2-Step group, the conventional two-step technique was used for enamel conditioning. In groups Delay0, Delay1, and Delay5, a SEP was used with various delays in curing time (0, 1, and 5 minutes). Stainless steel brackets were bonded to the specimens using composite resin adhesive and were tested for SBS. Then ARI scores were measured under naked eye, 2.5x, and 10x magnifications. The results showed no significant difference in mean SBS and the ARI scores between the SEP technique and the two-step technique. The findings also implied a delay up to 5 minutes in SEP curing time do not affect the SBS and ARI scores. Finally, there was no difference in the ARI scores measured under three levels of magnification.