Interrelationship between anatomical variations in mandibular teeth: a cone-beam computed tomography (CBCT) based...

Area of Science:

• Endodontics
• Dental Anatomy
• Radiology

Background:

• Understanding mandibular tooth root canal anatomy is crucial for successful endodontic treatment.
• Variations in root canal morphology can complicate endodontic procedures.
• Existing classification systems may not fully capture the complexity of mandibular tooth anatomy.

Purpose of the Study:

• To evaluate anatomical variations and interrelationships of mandibular anterior, premolar, and first molar teeth.
• To categorize and compare root canal anatomies using Vertucci and Ahmed's classification systems.
• To investigate the prevalence of distolingual roots (DLR) and their correlation with other anatomical features.

Main Methods:

• Retrospective analysis of 9,504 cone-beam computed tomography (CBCT) scans from 792 patients.
• Classification of root canal configurations using both Vertucci and Ahmed's systems.
• Evaluation of root counts, DLR presence, bilateral agreement, and cross-group correlations.

Main Results:

• Anterior teeth were single-rooted with significant internal morphological diversity.
• Mandibular first molars predominantly had two roots, with DLR (Radix Entomolaris) in 5.3%-6.8% of cases.
• A significant correlation was found between complex lateral incisor canals and ipsilateral MFM DLR (p=0.003, OR=2.23); males showed higher premolar complexity.

Conclusions:

• Mandibular teeth exhibit high morphological diversity and bilateral agreement.
• The Ahmed's system offers broader descriptive coverage for complex root canal anatomies than the Vertucci system.
• The correlation between lateral incisor canal complexity and MFM DLR warrants further investigation.