Diagnosis, classification, and frequency of C-shaped canals in mandibular second molars in the Lebanese population.

C-shaped canals are mostly found in mandibular second molars. Studies have shown that frequency ranges from 2.7 to 31%. This study was undertaken to provide further knowledge of the distribution of such canal anatomy, by determining the frequency of C-shaped canals in a sample representing the Lebanese population. Ninety-four mandibular second molars with scheduled endodontic treatment were examined over a 1-yr period. Of the 94 treated molars, 18 exhibited C-shaped canals that would represent 19.1% of the sample. The geographical position of Lebanon could represent an explanation for this phenomenon.