Middle mesial canal incidence and morphology in mandibular first molars: A cone-beam computed tomography and micro-computed tomography evaluation

Background: Mandibular first molar (MFM) being the first permanent posterior tooth to erupt, quite often gets involved in dental caries, which subsequently requires endodontic treatment in many cases. Thus, it is essential that the clinicians be aware of the root canal and the morphology of these teeth in detail. Over a period of years, the cases reporting with middle mesial canals (MMCs) in the MFMs have been seen on the rise; thus, it is imperative to know its incidence so that the data can be passed on to the clinicians for better management.

Aim: The aim of the current research was to evaluate the incidence of MMC in the MFMs using cone-beam computed tomography (CBCT) and further evaluating its morphology with micro-computed tomography (micro-CT).

Materials and methods: Five hundred and fifty extracted permanent MFMs were collected and subjected to CBCT scan. The teeth in which MMC was found, were further subjected to micro-CT to evaluate the detailed morphology.

Observations and results: The data exhibited the presence of MMC in 29 teeth out of 550 (5.27%). The most frequent morphological pattern observed in the MMC as per micro-CT was the confluent type (86.2%), followed by independent type (6.8%) and fin type (3.4%). Double MMC was observed in 1 tooth (3.4%).

Conclusion: The incidence of MMC was observed to be 5.27% and the confluent type of morphological configuration was the most common type noticed.