The Microscopic Structure of the Root Canal Morphology of the Distobuccal Root of the Maxillary First Molar in Japanese People: A Micro-Computed Tomography Study

抄録

In this study, ultra-high-resolution micro-computed tomography (micro-CT) was used to classify the root canal morphology of the distobuccal root of the maxillary first molar and investigate the incidence of accessory root canals, as well as to identify some aspects of their association with root canal re-infection during and after molar-infected root canal treatment. The specimens used were 100 maxillary first molars from Japanese individuals held in the collection of the Department of Anatomy of Tokyo Dental College. They were scanned by micro-CT, after which three-dimensional reconstruction was conducted, the pulp cavity and accessory root canals were observed, the root canal morphology was classified, and the incidences of the different types of accessory root canals were calculated. The distobuccal root of the maxillary first molar was a single root in all teeth from Japanese individuals. The main root canal was classified as Type I in 98.0% of cases, the incidence of lateral branches was 27.0%, and their incidence on the apical side was higher than that previously reported. These results suggest that, despite the simplicity of the root canal, the existence of accessory root canals should be borne in mind during root canal treatment.