RESUMO
A thorough knowledge of the root canal anatomy and an understanding of its variations from the normal are mandatory for the successful root canal therapy. The assessment and exploration of the accessory canal and apical delta is necessary to combat the persistent infection at the periapical area. The purpose of this study is to determine the morphological irregularities in the middle and apical 1/3rd region of the root canal system of maxillary incisors. A total of 100 maxillary incisors were decalcified, processed, sectioned at the middle and apical 1/3rd region and observed under an ordinary microscope. The frequency of accessory canals, apical delta and type of canal configuration were studied. Accessory canals were found in 5% of the teeth. There was absence of apical delta in all the specimens. Total specimens showed single canal extended from the pulp chamber to the apex (Type 1 canal configuration).