Aetiology, incidence and morphology of the C‐shaped root canal system and its impact on clinical endodontics

Abstract

The C-shaped root canal constitutes an unusual root morphology that can be found primarily in mandibular second permanent molars. Due to the complexity of their structure, C-shaped root canal systems may complicate endodontic interventions. A thorough understanding of root canal morphology is therefore imperative for proper diagnosis and successful treatment. This review aims to summarize current knowledge regarding C-shaped roots and root canals, from basic morphology to advanced endodontic procedures. To this end, a systematic search was conducted using the MEDLINE, BIOSIS, Cochrane Library, EMBASE, Google Scholar, Web of Science, PLoS and BioMed Central databases, and many rarely cited articles were included. Furthermore, four interactive 3D models of extracted teeth are introduced that will allow for a better understanding of the complex C-shaped root canal morphology. In addition, the present publication includes an embedded best-practice video showing an exemplary root canal procedure on a tooth with a pronounced C-shaped root canal. The survey of this unusual structure concludes with a number of suggestions concerning future research efforts.

Maxillary First Molar with One C-Shaped Fused Root Diagnosed with Cone-Beam Computed Tomography: A Case Report

“…Plenty of document information studied its incidence, morphology and clinical impact [11,12]. It is reported that the prevalence of C-shaped root canals in mandibular second molars was 39% in the Chinese population [13].…”

Three-dimensional imaging of internal tooth structures: Applications in dental education

“…In contrast to these commercial systems, Kato and colleagues [98] recently reported that freely accessible 3D models of teeth embedded into portable document format (PDF) files would constitute a valuable tool for dental students as well. In their study, four publication-embedded tooth models based on µCT datasets were presented that interactively permit the comparison of a tooth with regular root canal morphology and three teeth showing different types of C-shaped root canals [98 p. 1024].…”

Analytical methods and interpretation of variation in tooth morphology

“…The root canal system has been classified based on the canal pattern, and includes lateral branches, additional branches, and/or fused canals; the most popular criteria for the classification of root canals is the Vertucci's criteria [125,126]. A C-shaped root in the mandibular second molar is frequently found in the Japanese [130,131,[136][137][138][139][140] (reviewed by Kato et al [141]), and this unique root structure exhibits a complex root canal system.…”