•Purpose: to determine MB root canal configuration and incidence of MB2 in maxillary 1st molar.
•N= 208 extracted maxillary 1st molars.
•The MB roots were sectioned from a mesial approach in a BL direction, using a coarse sandpaper disk.
•The root canals were exposed, when possible, from the roof of the pulp chamber to the apex, and the typical configurations were classified and tabulated.
Most highlighted Results:
3 canals configuration were observed:
•Type I: single canal/single foramen.(48.5%).
•Type II: 2 canals/ 1 foramen, joining 1-4 mm from apex.(37.5%).
•Type III: 2 canals/2 foramina.(14%). •type IV: 1 canal / 2 foramina
•Established simple classification system to help in communication.