Root anatomy and apical canal morphology of maxillary first premolars

Understanding the root anatomy and apical canal morphology of maxillary premolars is a key prerequisite for successful surgical and endodontic treatment. The aim of this study was to assess the root anatomy and apical canal morphology of maxillary first premolars.To achieve the set task, 30 maxillary first premolars were extracted. After thorough rinse visual assessment of root anatomy was made. Each root was transversally sectioned six millimeters from apex with a straight hand piece. The apical samples were decalcificated in 7.5% trichloroacetic acid, transversal sections were made, stored in 10% formalin then dyed in hematoxylin and eosin and numerated from I to VI. Apical canal morphology was evaluated with an optical microscope.Majority of maxillary first premolars had double roots (63.0%; n=19) that were mostly separated (50.0%; n=15) containing a single root canal. Minority had double roots that were fused (13.0%; n=4) with two root canals. Single root with almost equal occurrence of two, as well as variable root canal configuration were found in (30.0%; n=9). A very rare occurrence of maxillary first premolars with three roots (7.0%; n=2) was detected, two vestibular and one palatal, each containing a single canal configuration. Accessory lateral canals were detected in 20% of maxillary first premolars. Transversal communications were detected in maxillary premolars with one root and double fused roots (26.6%; n=8). A single apical foramen was detected in majority of maxillary first premolars (50.0%; n=15). Two apical foramina were detected in (33.4%; n=10), three in (10.0%; n=3) and four in (6.6%; n=2) maxillary premolars.Keywords: maxillary first premolar, root anatomy, apical canal morphology, decalcification, optical microscopy