Anatomy assessment of permanent mandibular premolar teeth in a selected Iranian population using cone‑beam computed tomography

Abstract

Background: Appropriate cleaning and shaping and three‑dimensional obturation of the root
canal system lead to a successful endodontic treatment. To achieve this, complete knowledge of the
internal anatomy of root canals is necessary. Therefore, this study evaluated the number and shape
of mandibular premolar roots and canals and classified their Vertucci classification using cone‑beam
computed tomography (CBCT) images of an Iranian sample population.
Materials and Methods: This in vivo study was performed on CBCT images of patients aged
20–70 years who had attended a dental radiology center in Isfahan. CBCT images were examined
in coronal, sagittal, and especially axial dimensions. Descriptive statistics were calculated. Groups
were compared using the Chi‑square of the Statistical Package for the Social Sciences. The level of
significance was predetermined as 0.05.
Results: In both first and second premolars, the most common classes were Type I followed by
Type V. The Chi‑square did not show significant differences between males and females in terms of
Vertucci classes in the first (P = 0.305) or second premolar (P = 0.315).
Conclusion: Since a thorough knowledge of root canal anatomy is necessary for successful root
canal treatment and almost one out of ten mandibular premolars has additional canal in their root
canal system, accurate evaluating of preoperative radiographs, taking CBCT images if necessary,
and probing the root canal system with fine and precurved files should be done to negotiate the
entire canal system.
Key Words: Bicuspid, cone‑beam computed tomography, root canal therapy