ENAMEL PREPARATION FOR ORTHODONTIC BONDING - A COMPARISON BETWEEN, THE USE OF A SANDBLASTER AND CURRENT TECHNIQUES

Four methods of enamel preparation before orthodontic bonding that are currently in use or proposed for use were investigated. The study con sisted of two parts. Part one evaluated the roughness of the prepared enamel surfaces by using optical profilometry and scanning electron mi croscopy (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 on ly sandblasted. In group B, the surfaces were sandblasted and acid etc hed. 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. Th ere was no statistical difference in surface roughness among the four groups at p < 0.05, nor was there any statistical difference in bond s trength among the three groups that were acid etched. However, there w as 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 ena mel surface and can therefore be used as a substitute for polishing wi th pumice. It should be followed by acid etching to produce enamel sur faces with comparable bond strengths.