Aim: Detection of the prevalence of bifid mandibular canal and classification of its types in the Egyptian population.
Methodology: Radiographic examination of 329 mandibular sides was done using Planmeca Promax 3D Mid CBCT machine. The scans varied depending on patients' sizes (according to the manufacturer's recommendations) using different FOVs with the same voxel size (0.4 mm (400 μm)). The bifid the mandibular canal was observed and classified according to Naitoh`s classification (retromolar, dental, forward, and buccolingual canals). In addition, the prevalence of location of accessory canal types and the mean distance to the alveolar ridge and teeth were reported.
Results: In 329 hemimandibles, there were 101 bifid canals (30.7%) and 37 trifid canals (11.2%). The dental canal type was the most common (43.3%), followed by retromolar canal type (33.7%), forward canal type (17.2%), and buccolingual canal type (5.7%). The forward canals and the dental canals had statistically similar mean distances of 11.1 ±2.1 and 11.1±2.5 mm respectively. The accessory canals were at a significantly longer mean distance (12.1±1.6 mm) to the alveolar crest in the premolar area compared to distance in the molar area (10.9 ± 2.3 mm). Retromolar canals showed a significantly longer distance of 13.8± 4.4 mm.
Conclusions: Examination of the mandibular canal is mandatory by surgeons to minimize the chance of missing any accessory branches, since its prevalence was more than 40% with 21.3 % presented with bilateral manifestation.