Do mandibular molars commonly hold “extra” canals?
A. Mandibular Molars routinely have significant variations within what has become known as “normal anatomy”. Clinicians need to check the mesial root for a third system which may be displaced or located within the groove between the MB and mesiolingual (ML) orifices. The broad distal root commonly contains an extra canal which may be separate along its length or become contiguous following cleaning and shaping procedures. Importantly, even when the distobuccal (DB) and distolingual (DL) systems are common, deep divisions should be expected and post treatment films routinely demonstrate multiple apical portals of exit.
