Anatomical variations of mandibular first molar and their implications in endodontic treatment.

The possible variations of anatomical and morphological characteristics of the teeth are very important especially for the endodontic practitioner. Before beginning any kind of endodontic treatment, the clinician must be always take into account the morphological variations in pulp anatomy. Among all human teeth, the mandibular first permanent molar is one of the most important. It is often affected by caries and usually needs root canal treatment, even at an early age. For the success of its endocanalicular treatment, dentists need to locate all root canals, debride them entirely, and after that fill the whole endocanalicular system with an inert root filling material. Unfilled canals, left like this because they were not detected, can compromise the longevity of the tooth, thus being a source of infection and a main cause of failure of the prosthetic treatment. This article presents two clinical cases of right mandibular first molars with two roots and four canals instead of three.