Roughness of enamel surfaces after different bonding and debonding procedures
Four methods of enamel preparation before orthodontic bonding that are currently in use or proposed for use were investigated. The study consisted of two parts. Part one evaluated the roughness of the prepared enamel surfaces by using optical profilometry and scanning electron microscopy (SEM). Part two compared the debonding force for the prepared enamel surfaces by using a mechanical testing machine. The teeth were divided into four groups as follows: In group A, the surfaces were only sandblasted. In group B, the surfaces were sandblasted and acid etched. In group C, the surfaces were buffed with an 1172 fluted bur and acid etched. In group D, the surfaces were pumiced and acid etched. There was no statistical difference in surface roughness among the four groups at p < 0.05, nor was there any statistical difference in bond strength among the three groups that were acid etched. However, there was a significant difference in bond strength between these groups and the group that received only sandblasting (no acid etching). Thus, in this preliminary study, sandblasting does not appear to damage the enamel surface and can therefore be used as a substitute for polishing with pumice. It should be followed by acid etching to produce enamel surfaces with comparable bond strengths.