Cone Beam Computed Topographic Evaluation and Endodontic Management of a Rare Mandibular First Molar with Four Distal Canals

Abstract

Root canal system is complex to understand because of its unpredictable nature. It differs for different teeth and for the same teeth in different individuals. Successful endodontic therapy thus depends on the clinician's ability to anticipate and look for these variations. A mandibular first molar with six root canals represents a rare anatomical variant, particularly when four canals are found in distal root. This case report discusses successful nonsurgical endodontic management of two-root mandibular first molar with four distal canals and two mesial canals reported for the first time in Indian population. Cone beam computed tomography was used as a diagnostic method to confirm the position and presence of 4 root canals in the distal root.

Morphology and prevalence of middle canals in the mandibular molars: A systematic review

“…Later, an additional configuration – double middle mesial/distal, i.e., four canals in one root, was also reported. [ 37 47 50 56 63 66 75 76 77 78 79 ] These four canals can be independent, exiting from four separate foramina[ 63 ] or confluent with one middle canal joining the ML and the other joining the MB and exiting as two canals from two foramina[ 66 76 77 78 79 ] or all four joining and exiting from one foramen. [ 50 ]…”

“… Mandibular first molar with MMC[ 3 42 43 44 45 46 48 49 52 53 54 55 56 59 60 61 67 70 71 72 73 74 80 ] Mandibular second molar with MMC[ 43 72 ] Mandibular first molar with MDC[ 51 57 64 65 68 ] Mandibular first molar with MMC and MDC[ 3 53 55 56 71 73 80 ] Mandibular first and second molar with double middle mesial[ 47 50 66 75 78 ] Mandibular first molar with double distal canal[ 63 76 77 79 ] Mandibular first molar with DMMC and MDC[ 47 ] Mandibular second molar with DMMC and MDC[ 78 ] Mandibular first molar with DMMC and double MDC[ 77 ] Mandibular first molar with one distal root with three canals at orifice exiting as two canals[ 64 ] Mandibular first molar with two distal roots, with one canal at the orifice and apex in one root and two canals at the orifice exiting as one canal at the apex in the other root[ 40 41 ] Mandibular first molar with two distal roots with two independent canals in each root[ 63 ] Mandibular first molar with three distal roots with one canal in each root[ …”

Endodontic treatment of the mandibular first molar with six root canals: A case report and literature review

“…However, there are a limited number of case reports on the rare anatomical configuration with six root canals in the mandibular right first molar. A detailed review of case reports of mandibular first molars with six or more root canals in the last 12 years is summarized in Table Ⅰ (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). These studies were retrieved from a database (https://www.x-mol.com/) using the following search terms: Mandibular first molar, middle distal canal, middle mesial canal, six canals, tooth anatomy, extra root.…”

Endodontic management of a mandibular first molar with six root canal systems

“…The mandibular first molar is considered to be the most common tooth to involve in the endodontic procedure because it is earliest permanent tooth to erupt. [ 3 ] Because of the greater number of endodontic treatments involving this tooth, the clinician may be confronted in many cases of mandibular first molars with variation in root (single root,[ 4 ] four roots,[ 5 ] taurodontism,[ 6 ] radix entomolaris,[ 7 ] Radix paramolaris[ 8 ]) and internal anatomy (middle mesial,[ 9 10 11 12 13 14 ] middle distal,[ 5 9 13 14 15 16 ] and C-shape[ 17 18 ]). However, presence of four canals in the mesial root is extremely rare.…”