Mandibular first molar with three roots and four canals: A case study

Endodontic treatment requires a thorough knowledge of the anatomy of the teeth and their surrounding structures. Root canals may be left untreated during endodontic therapy if dentist fails to identify their presence, particularly in the teeth with anatomic variations or extra root canal. A major anatomical variation of the two rooted mandibular first molar is a tooth with an additional root located lingually (the radix entomolaris) buccally (radix paramolaris). The prevalence of these three rooted mandibular first molars appears to be less than 3% in African population, not to exceed 4.2% in Caucasians. To be less than 5% in Eurasian and Asian populations, and to be higher than 5% (even upto 40%) in populations with Mongolian traits. As far as the access was concerned, entering the root canal in RE required a modification of opening in a distolingual direction resulting in a trapezoidal opening cavity. None of the orifices was located midway between the mesial and distal component.