Three‐dimensional morphological analysis of C‐shaped canals in mandibular first premolars in a Chinese population

Fan B, Ye W, Xie E, Wu H, Gutmann JL. Three‐dimensional morphological analysis of C‐shaped canals in mandibular first premolars in a Chinese population. International Endodontic Journal , 45 , 1035–1041, 2012. Abstract Aim To investigate and compare the unique anatomical features and positioning of C‐shaped canals in mandibular first premolars with and without radicular grooves in a Chinese population. Methodology A total of 327 extracted mandibular first premolars including 146 with radicular grooves and 181 without radicular grooves from a Chinese population were scanned by μCT‐50 or μCT‐80. After reconstruction, canal systems were classified according to a modified Vertucci method and the anatomical features evaluated. The data were analysed by one‐way anova test, Chi‐square test and Fisher’s exact test ( P < 0.05). Results Of 146 mandibular first premolars with a radicular groove, 97 had C‐shaped canals, the predominant anatomical canal type being Vb ( P < 0.001), which was characterized by an oval canal in the coronal part and a semicolon or continuous C‐shape beneath the groove. Of the 181 mandibular first premolars without a radicular groove, no C‐shaped canal system was observed, and the percentage of Ia (97.8%) was significantly higher than those of other types ( P < 0.001). Conclusion In teeth from a Chinese population, mandibular first premolars with radicular grooves had a high incidence of C‐shaped canal systems with anatomical variations along the root.