Methods: The study included 36 extracted teeth (12 incisors, 12 canines, and 12 premolars) that were randomly assigned to one of three groups that had resin removed with either a 1) composite scraping plier, 2)12-fluted carbide finishing bur, or 3) 30-fluted carbide finishing bur. All the teeth were embedded in plaster with their facial surfaces exposed; brackets were bonded to the teeth with a light-cured adhesive (Transbond, 3M Unitek) according to the manufacturer's instructions; the brackets were removed after 24 hours using debonding pliers; the surfaces were polished with a slurry of fine flour of pumice, followed by brown and green polishing cups. Using a contact surface profilometer, 4 blinded measurements of roughness were made prior to bonding (T0), after resin removal (T1), and after polishing (T2). The groups were compared using non-parametric tests.
Results: The initial (T0) measurements showed no statistically significant group differences (p>.05). Facial surface roughness after the brackets had been removed (T1) was significantly greater when the resin was removed with the scraping pliers than with either the 12- or 30 fluted burs. There were no significant differences in surface roughness between the 12- and 30 fluted burs. Polishing significantly decreased the surface roughness of the 12- and 30 fluted bur groups; it had no effect on the scraped surfaces.
Conclusions: The 12- or 30-fluted burs had less effect on enamel surface roughness after resin removal than scraping pliers, and the burs hold greater potential for smoothing the facial surface by polishing. Composite removal with scraping pliers should, therefore, be a concern for the clinical orthodontist.