VAN 121: Veterinary Gross Anatomy-II (2+2)

MANDIBULAR NERVE

• The mandibular nerve is a mixed nerve. Its sensory root arises from the semilunar ganglion soon after it is joined by the motor root. The motor fibres supply only the muscles of mastication. The mixed nerve thus formed leaves the cranium through the foramen ovale, runs downwards between the pterygoids, enters the mandibular foramen of the mandible, runs through the inferior dental canal and gains exit at the mental foramen. Before entering the mandibular canal. It gives off a number of branches in its course.
  • Masseteric nerve: Passes through the mandibular notch enters the deep face of the masseter and supplies it.
  • Deep temporal: To supply temporalis muscle.
  • Buccinator nerve: Passes downward and forward on the medial aspect of temporo mandibular articulation, runs downward in the submucous tissue of the cheek and supplies mucosa of the cheek.
  • Pterygoid nerve: Arises in common with the preceding and supplies the pterygoid muscles and branches to tensor palati and tensor tympani.
  • Mylohyoid nerve: Passes downward to supply the mylohyoideus muscle and also the anterior belly of digastricus.
  • Superficial temporal nerve: Passes backward to the posterior border of the mandible a little below its neck turns outward and then forward under the parotid lymph gland and divides into transverse facial nerve, supplying skin of the cheek and a ventral branch which unites with the dorsal buccal division of the facial nerve. It also gives a branch to parotid salivary gland that conveys postganglionic secretomotor fibres from otic ganglion.
  • Lingual nerve:Runs downwards and forward between the ramus of the mandible and medial pterygoid muscle to the root of the tongue, where it divides into a superficial branch, which accompanies the mandibular duct on the deep face of the sublingual gland and supplies the mucous membrane of the tongue and floor of the mouth and a deep branch, which runs between hyoglossus to the tip of the tongue. It supplies the mucous membrane of the anterior two third of the tongue.
• In the course of the mandibular nerve through the mandibular canal,it supplies dental branches to lower cheek teeth, and sends a branch through the incisor canal to supply lower incisors. After emerging out of the mental foramen, the nerve divides into a number of labial filaments to supply the lower lip.