Association Between Middle Mesial Canals and Additional Distal Root Canal Anatomy in Mandibular First Molars: A Cone-Beam Computed Tomography Study in an Iranian Population

Background

A comprehensive understanding of root canal morphology is essential for successful endodontic treatment. Anatomical variations such as middle mesial canals (MMCs), second distal canals, and additional distal roots may complicate canal identification and instrumentation. Although the prevalence of these anatomical features has been investigated in different populations, evidence regarding their potential coexistence within the same tooth remains limited. This study evaluated the prevalence of MMCs and their association with second distal canals and additional distal roots in mandibular first molars using cone-beam computed tomography (CBCT) in an Iranian population.