Biometric Analysis of C-shaped Root Canals in Mandibular Second Molars Using Cone-Beam Computed Tomography

Area of Science:

• Endodontics
• Dental Anatomy
• Radiology

Background:

• C-shaped root canals present unique anatomical challenges in endodontic treatment.
• Understanding root canal morphology is crucial for successful root canal therapy.

Purpose of the Study:

• To assess the configuration of C-shaped root canals.
• To determine root canal wall thickness and the orientation of the thinnest area.
• To analyze these features in mandibular second molars using cone-beam computed tomography (CBCT).

Main Methods:

• Evaluation of 75 CBCT scans of mandibular second molars.
• Analysis of axial sections to determine C-shaped canal configurations (coronal, middle, apical).
• Determination of root canal path, thinnest root canal wall, and its orientation; statistical analysis using ANOVA and Tukey's test.

Main Results:

• Melton's type I was most common in coronal/middle regions; types I and IV in the apical region.
• Mean thinnest wall thickness decreased apically (1.94mm coronal, 1.42mm middle, 1.10mm apical).
• The lingual wall was consistently the thinnest, particularly in the apical region and on the mesial root.

Conclusions:

• The lingual wall is the thinnest in C-shaped root canals of mandibular second molars in an Iranian population.
• Canal type, number, and pathway exhibit variability from orifice to apex.
• CBCT is valuable for assessing complex root canal anatomy.