LAUSR

OBJECTIVE To assess the effect of chitosan, at concentrations of 2.5% and 5.0%, on the wettability of the eroded dentin, followed by analysis of surface morphology by SEM. METHODS 104 bovine dentin slabs were ground, polished and then immersed in 20mL of citric acid (pH=3.2) under continuous stirring for 2h. Specimens were randomly divided according to the dentin substrate: sound and eroded, and then, subdivided into 4 groups (n=10): without rewetting (control), 1% acetic acid, 2.5% chitosan and 5.0% chitosan. Then, a drop of the adhesive system Single Bond 2 (3M) was deposited onto surface of each specimen. The contact angle between dentin surface and the adhesive system was measured by using a goniometer. The other 24 specimens were subjected to analysis under SEM. Statistical analysis was performed using the normality test (Kolmogorov-Smirnov) and Analysis of Variance (ANOVA) (p>0.05). RESULTS No differences were found between the angles produced on the eroded dentin rewetting with chitosan at the concentrations of 2.5% and 5%. CONCLUSION The chitosan, regardless of the concentration used, did not influence the eroded dentin wettability. Through SEM analysis, it was found particles of chitosan deposited on the surface and within the dentinal tubules.