Micro CT Study Of Root Canal Morphology Of Mandibular First Premolars

Experiment 1 Investigation on the type V root canal configuration of the mandibular first premolars with radicular groove by micro-computer tomographyObjective:To investigate the root anatomy and canal configuration of the mandibular first premolars with radicular groove in root surface by micro-computer tomography(Micro-CT).Methods:58 mandibular first premolars with radicular groove were selected.The 3-dimensional images of the teeth and canal system morphology were reconstructed by Micro CT.The types of canal configuration were classified,and the position and angle of Vertucci V root canal bifurcation were measured.The location and incidence of the accessory canals were recorded.The location of the apical foramen,the wall thickness and the diameter of the root canal were analyzed.Results:The most common type of root canal in mandibular first premolar with radicular groove was type V canal.In this study,cases of type V accounted for 55.2%.Root canal furcation of type V mandibular first premolar located about 6.13 millimetres below the cemento-enamel junction(CEJ).Significant differences were found in the apical position,wall thickness and root canal diameter between the buccal and lingual canal.Conclusions:The root canal morphology of mandibular first premolars with radicular groove was complex,with a high incidence of type V canals.Understanding the anatomic features of the root canals can greatly help clinical treatment.Experiment 2 A comparative study on the morphology between type I root canal and type V root canal of mandibular first premolar by micro-computer tomographyIntroduction:To investigate the root anatomy and canal configuration of the mandibular first premolars with radicular groove in root surface by micro-computer tomography(Micro-CT)Methods:50 mandibular first premolars without radicular groove were selected.The 3-dimensional images of the teeth and canal system morphology were reconstructed by Micro CT.The types of canal configuration were classified.The location and incidence of the accessory canals were recorded.The location of the apical foramen,the wall thickness and the diameter of the root canal were analyzed.Results:The most common type of root canal in mandibular first premolar without radicular groove was type I canal.In this study,cases of type I accounted for 94%.Significant differences were found in the apical position,wall thickness and root canal diameter between the type I and type V root canal.Conclusions:The root canal morphology of mandibular first premolars without radicular groove has a high incidence of type I root canals.Significant differences were found in the apical position,wall thickness and root canal diameter betvween the type I and type V root canal.Understanding the anatomic differences of these root canals can greatly help clinical treatment.