Isfahan University of Medical SciencesDental Research Journal1735-33273120080120Root Canal Morphology of Human Mandibular Incisors in Yazd Province3232F.Ezoddini. drj@dnt.mui.ac.irZ.MohammadiM.Tabrizizadeh20101106Introduction An in vitro study was performed to determine the number and the type of root canals of mandibular incisor teeth in an Iranian population. Methods and Materials Sixty eight mandibular incisor teeth were immersed in India ink decalcified and cleared. Results It was found that 55.9% of the teeth had two canals that in 51.5% of them the canals merged into one canal before exiting the tooth through one apical foramen. Discussion Because of high percentage of two canals in lower mandibular incisors, there should be more attempt to detect the second canal during access preparation. Key words Root Canal Morphology, Mandibular Incisors, Yazd.