Correlation between presence of radix entomolaris in mandibular first molars and C-shaped canals in mandibular second molars: a sample of CBCT scans in Taiwanese students


  • Magdalena Piskórz Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin
  • Ingrid Różyło-Kalinowska Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin
  • Karolina Futyma-Gąbka Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin
  • Zuzanna Aleksandrowicz Student Reserach Group at the Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin
  • Anna Błaszczyk Student Reserach Group at the Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin
  • Wiktoria Furmanek Student Reserach Group at the Department of Dental and Maxillofacial Radiodiagnostics, Medical University of Lublin



root canal anatomy, cone beam computed tomography, C-shaped root canals, Taiwanese, radix entomolaris


The anatomy of root canals is so complex that in many cases it is not sufficient to take an intraoral radiograph to diagnose the number and shape of root canals. Therefore, Cone Beam Computed Tomography (CBCT) facilitating diagnosis and treatment planning in endodontics is gaining more and more importance. Radix entomolaris is an extra root which is found in mandibular molars and located distolingually. C-shaped canal is most commonly found in mandibular second molars and can differ significantly in shape from the typical anatomy of lower molars. The aim of the study was to evaluate the correlation between presence of radix entomolaris in mandibular first molars and presence of C-shaped mandibular second molars in Taiwanese students based on CBCT scans. The material consisted of 19 CBCT examinations taken in the Department of Dental and Maxillofacial Radiodiagnostics of the … Among 19 CBCT examinations 5 cases of coexistence of additional root and C- shaped canals were found. Up to 80.0% of cases were bilateral. In the studied sample there was high coincidence of radix entomolaris in mandibular first molars and C-shaped mandibular second molars. Knowledge of this correlation will prevent diagnostic errors during endodontic and surgical treatment planning.



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