Answer:
The mandibular canal, also referred to as the Inferior Alveolar Canal (IAC), sits within the mandible. It serves the purpose of housing the inferior alveolar nerve which is responsible for supplying sensation to the lower teeth.
This canal also houses the inferior alveolar vein - a dental vein whose function is to (with the assistance of the posterior alveolar artery) drain blood from the lower teeth and jaw.
A picture of the mandibular canal is attached.
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