Table 1.

Frequency of MB2 canals according to the four methods tested and the reference standard (root cross-sectioning) (n=147)

Method	Absolute frequency (%)
Direct visual	43 (29.25)*
Loupe	45 (30.61) *
Microscope	51 (34.69)
CBCT	64 (43.54)
Cross-sectioning	61 (41.50)

MB2=second canal of mesiobuccal roots; CBCT = cone-beam computed tomography;

^* Statistically significant differences between the method and reference standard