The first step of each endodontic treatment is the scouting of the root canal with a stainless steel hand file which provides information on the canal diameter, its curvature and its level of mineralization. The level of mineralization of the canal lumen and the degree of curvature determine the treatment’s difficulty and thus the most suitable sequence for the clinical case. This information completes the one obtained through the preoperative x-ray so that possible obstacles and difficulties can be foreseen.