The success of endodontic therapy relies on thorough debridement, shaping and completely filling the entire root canal system.Failure to recognize additional canal results in poor prognosis of the treatment. The advance in the technology and knowledge and experience of the clinician has led to meticulous attention in locating as well as treating these extra canals successfully. Middle mesial canal is an additional canal found in the mesial root of mandibular molars. These canals may either merge with the main canal or may leave as an independent canal. The present case report describes the successful treatment of three independent mesial canals in mandibular second molar

Keywords: Middle Mesial Canal; Mesial Root; Mandibular Second Molar.