Enamel morphology after microabrasion with experimental compounds

BACKGROUND: Enamel microabrasion is an esthetic treatment for removing superficial stains or defects of enamel. AIM: This study evaluated the roughness after enamel microabrasion using experimental microabrasive systems. MATERIALS AND METHODS: One hundred and ten samples (5 × 5 mm) were obtained from bovine incisors and divided into 11 groups (n = 10) in accordance with the treatment: Microabrasion using 6.6% hydrochloric acid (HCl) or 35% phosphoric acid (H(3)PO(4)) associated with aluminum oxide (AlO(3)) or pumice (Pum) with active application (using rubber cup coupled with a micro-motor of low rotation) or passive application (just placing the mixture on the enamel surface); just the use of acids in a passive application (negative control), and a group without treatment (positive control). Roughness analysis was performed before and after treatments. The statistical analysis used analysis of variance (PROC MIXED), Tukey-Kramer and Dunnet tests (P < 0.05). Representative specimens were evaluated using scanning electron microscopy (SEM). RESULTS: There was no significant difference between the acids used (P = 0.0510) and the applications (P = 0.8989). All of the treated groups were statistically different from the positive control. When using passive application, the use of HCl + AlO(3) resulted in higher roughness when compared with HCl + Pum. Additionally, this treatment was statistically different from the passive application of H(3)PO(4) (negative control) (P < 0.05). However, SEM analysis showed that the treatment with AlO(3) resulted in an enamel surface with a more polished aspect when compared with Pum. CONCLUSION: AlO(3) may be a suitable particle for use in microabrasive systems.