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Published on: September 8, 2023
Worldwide Prevalence of Mandibular Second Molar C-Shaped Morphologies Evaluated by Cone-Beam Computed Tomography
Murilo von Zuben1, Jorge N R Martins1, Luiza Berti2
1Department of Endodontics, Faculdade de Medicina Dentária, Universidade de Lisboa, Lisboa, Portugal.
Introduction:
The aim of this study was to evaluate and compare the C-shaped mandibular second molar prevalence in different regions around the world with the aid of cone-beam computed tomography technology.
Methods:
Nine field observers from 9 different geographic regions were calibrated. A total of 400 samples were collected in each region. The prevalence of C-shaped anatomy was calculated. The number of roots and the configuration of the C-shaped canals at 3 different axial levels were also evaluated. The z-test was used to analyze the difference between the means of each independent group. Intrarater reliability was also tested.
Results:
A total of 3600 teeth from 2735 patients were included in this research; 499 teeth presented C-shaped root canal configuration, representing a global prevalence of 13.9%. China had a prevalence of 44.0%, which was significantly higher than any other region. The C-shape prevalence in women was 16.5%, which was significantly higher than the 10.4% prevalence found in men. No difference between sides (37 or 47) was evident in the global sample.
Conclusions:
Cone-beam computed tomography is a valuable tool to evaluate the C-shaped root canal configuration in vivo. In the present study, China presented the highest prevalence of C-shaped mandibular second molars when compared with other regions. Women exhibited a higher prevalence than men.
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