Prevalence of Second Root and Root Canal in Mandibular and Maxillary Premolars Based on Two Classification Systems in Sub-Population of Northern Region (Saudi Arabia) Assessed Using Cone Beam Computed Tomography (CBCT): A Retrospective Study.

The objective of this paper is to assess the prevalence of a second canal in maxillary and mandibular premolars based on two classification systems of root canal morphology using Cone beam computed tomography (CBCT) images. A total of 286 CBCT scans from the archive of the Radiology department of a hospital were assessed for the presence of a second canal in maxillary and mandibular premolars. The canal configuration and its assessment was undertaken using Vertucci and Ahmed's classification. A Chi-square test was used to test the significance of the difference between gender and age. A total of 286 premolars were examined (217 mandibular premolars and 69 maxillary premolars); of these, 173 teeth (60.5%) were from males and 113 were from females (39.5%). Some 62% of maxillary left first premolars had two roots, followed by maxillary right first premolars (47%), and then maxillary left second premolars (30%) and maxillary right ones (27%), respectively. Type IV Vertucci were seen in maxillary premolars, while type I were ordinarily seen in the included mandibular premolars. Surprisingly, Vertucci type III was only found in mandibular left first premolars at a frequency of 2%. One orifice with two separate canals and two orifices of two distinct canals with two portals of exit were predominantly noticed with maxillary first premolars ( FP B P) in 73% and 81%, respectively, followed by ( FP ) 19%. The prevalence of a second canal in maxillary and mandibular premolars was low in the investigated premolars in comparison to the premolars that had just one root and canal, as assessed based on Vertucci and Ahmed's root canal system classification.