To evaluate the effectiveness of Carisolv™and different auxiliary chemical substances in root canal smear layer (SL) removal. SL was produced in the centre of 40 hemi-disks of bovine root dentine. The samples were divided into four irrigation groups (G): GI (control) -0.9% NaCl; GII -1% NaOCl + 0.9% NaCl; GIII -Carisolv™ + 0.9% NaCl; GIV -1% NaOCl + 10% citric acid solution + 0.9% NaCl. The photomicrographs (SEM analysis) were coded (0 -absence of SL; 1 -moderate SL; 2 -dense SL with visible tubules; 3 -dense SL with no visible tubules). GIV was more effective in SL removal (P < 0.01). It should be noted that GI and GIII obtained score 3 in 100% of the samples (P > 0.01). Conclusion: NaOHCl, citric acid and NaCl solutions, when used together, presented a better performance in the removal of SL when compared to the other solutions. (J. Oral Sci. 48, [99][100][101][102][103] 2006)