Middle distal canal of mandibular first molar: A case report and literature review.

A successful root canal treatment can only be achieved by gaining adequate access to all root canals, ensuring adequate mechanical preparation, and disinfection as well as placing a three-dimensional impermeable filling in these root canals. Practitioners must be very careful when detecting the root canals in mandibular first molar tooth, because it shows a wide variety of root canal variations and it is the first permanent tooth erupted in the mouth that frequently requires endodontic treatment. Our case report presents the endodontic retreatment of a left permanent mandibular first molar having two roots that consist of three distal canals and two mesial canals (Type XVIII root canal pattern). After all the root canals were identified with endodontic explorer adequate preparation and disinfection were provided, the root canals were filled with calcium hydroxide-based canal sealer and gutta-percha and the crown was restored with resin composite at the second appointment. In addition, a short review of literature for similar cases is presented in this paper.