Fig. 1.

New system of classification for the morphology of root canal of left mandibular first premolar classified with the new system of classification, narrated as code ¹35¹. The code is consisting of three components, first is the tooth number represented by the blue arrow, the second is number of roots symbolized by the green arrow and the third is the configuration of the canal depicted by the black arrow. A superscript before the tooth number is written which indicates the number of roots, so it is one root with tooth number (35). Details about the configuration of the canal are displayed as superscripts after the tooth number, during the passage of the root canal starting from the orifices [O], passing through the canal [C], and ending by the foramen [F], so it is one canal