Mandibular Nerve Anatomy and Function

Mandibular Nerve

• The mandibular nerve has both sensory and motor fibers and supplies the teeth and gums of the mandible, the skin of the temporal region, the auricula, the lower lip, the lower part of the face, and the muscles of mastication.

Course and Relations of the Mandibular Nerve

• The mandibular nerve begins in the middle cranial fossa through a large sensory root and a small motor root.
• The sensory root arises from the lateral part of the trigeminal ganglion and leaves the cranial cavity through Foramen Ovale.
• The motor root lies deep to the trigeminal ganglion and to the sensory root, and also passes through the foramen ovale to join the sensory root.
• The main trunk passes through the infratemporal fossa and divides into a small anterior division and a large posterior division.

Branches of the Mandibular Nerve

• The main trunk has several branches:
  • Meningeal branch (Nervus Spinosus): supplies the dura mater of the middle cranial fossa and enters the skull through Foramen Spinosum with the middle meningeal artery.
  • Nerve to medial pterygoid: supplies the medial pterygoid from its deep surface and gives a motor root to the otic ganglion.
  • Buccal nerve: a sensory branch that supplies the skin and mucous membrane related to the buccinator and the labial aspect of gums of molar and premolar teeth.
  • Masseteric nerve: supplies the masseter muscle.
  • Deep temporal nerves: supply the temporalis muscle.
  • Nerve to lateral pterygoid: supplies the lateral pterygoid muscle.

Posterior Division

• The posterior division has several branches:
  • Auriculotemporal nerve: a sensory nerve that supplies the skin of the temporal region and the auricula.
  • Lingual nerve: a sensory nerve that supplies the tongue and joins the chorda tympani nerve.
  • Inferior alveolar nerve: the largest terminal branch that supplies the teeth and gums of the mandible.

Inferior Alveolar Nerve

• The inferior alveolar nerve runs vertically downwards lateral to the medial pterygoid and to the sphenomandibular ligament.
• It enters the mandibular foramen and runs in the mandibular canal accompanied by the inferior alveolar artery.
• The mylohyoid branch contains all motor fibers of the posterior division and supplies the mylohyoid muscle and the anterior belly of the digastric.