THE EFFECT OF MICROABRASION ON RESTORATIVE MATERIALS AND TOOTH SURFACE

The effect of microabrasion on human enamel has been well documented; however, no information is available on its effect on dentin or restor ative materials. The purpose of this study was to evaluate the effect of the microabrasion technique on the surface roughness of restorative materials and enamel and dentin surfaces. Flat disks of amalgam, comp osite resin, porcelain, and glass ionomer were evaluated. Labial ename l of three maxillary incisors and three molars that were flattened buc cally to expose dentin were also tested. The Prema microabrasion compo und was applied to each sample with a 10:1 gear-reduction, slow-speed handpiece for 5 seconds, then rinsed for 10 seconds. Roughness was det ermined with a profilometer. This procedure was repeated 20 times for each sample. A polyvinylsiloxane impression of the surface was taken a fter 0, 5, 10, 15, and 20 applications and examined under a scanning e lectron microscope. Enamel surface roughness did not improve as previo usly reported, suggesting that changes in optical characteristics may not be as important as removal of enamel in obtaining esthetic results . Dentin and glass ionomer exhibited an increase in roughness, such th at their presence contraindicates the technique. Amalgam was essential ly polished. Porcelain was most resistant to the effects of microabras ion. Judicious use of the technique, especially when restorative mater ials are present, is advised.