Bifid mandibular canals: prevalence and implications

Abstract

Purpose: Bifid mandibular canals (BMCs) are variations of the normal anatomy, with a reported prevalence ranging from 0.08 to 65%. Aberrations of the mandibular canal can have important clinical implications. We therefore sought to assess the prevalence of BMCs and discuss several surgical implications that may be associated with this variation.

Materials and methods: A retrospective chart study of available digital panoramic images from our file archives from 2011 to 2013 was performed to search for the prevalence of BMCs; to this end, 5,000 consecutive panoramic radiographs of patients aged 18 to 80 years were studied. Detection of BMCs was based on visualization of 2 radiolucent lines and at least 3 radiopaque borders on the monitor and confirmed by 2 oral and maxillofacial surgeons and 2 dentists. The types of bifidity also were assessed and recorded. Data analysis was performed using the χ(2) test.

Results: BMCs were observed in 61, or 1.2%, of 5,000 digital panoramic images. There were no statistically significant correlations found regarding age or gender. The most frequently encountered type of bifid canal was type 2 (82%).

Conclusions: The prevalence of BMCs seen on panoramic images in this study was 1.2% and was not correlated with age or gender.