The mandibular nerve controls the mandible.
The mandibular nerve, also known as the mandibular division of the trigeminal nerve (CN V3), is responsible for both sensory and motor functions related to the mandible (lower jaw). It's the only branch of the trigeminal nerve (CN V) that carries motor fibers.
Sensory Functions
The mandibular nerve provides sensory innervation to:
- The lower teeth and gums.
- The skin of the lower face, including the chin and lower lip.
- Part of the tongue (general sensation, not taste).
- The lining of the cheek.
Motor Functions
The motor fibers of the mandibular nerve control several muscles, including:
- Muscles of Mastication (chewing): These are the primary muscles involved in moving the mandible for chewing.
- Masseter
- Temporalis
- Medial Pterygoid
- Lateral Pterygoid
- Other Muscles:
- Mylohyoid
- Anterior belly of the digastric
- Tensor veli palatini
- Tensor tympani
Branches of the Mandibular Nerve
The mandibular nerve has several branches that carry these sensory and motor fibers. Some key branches include:
- Inferior Alveolar Nerve: Provides sensory innervation to the lower teeth. A branch of this nerve, the mental nerve, emerges from the mental foramen in the mandible and provides sensation to the chin and lower lip.
- Lingual Nerve: Carries sensory information from the anterior two-thirds of the tongue (general sensation) and joins the chorda tympani (from the facial nerve) which carries taste sensation.
- Buccal Nerve: Provides sensory innervation to the cheek.
- Motor Branches: Directly innervate the muscles of mastication, mylohyoid, anterior digastric, tensor veli palatini and tensor tympani.
In summary, the mandibular nerve is crucial for both sensation and movement related to the mandible and surrounding structures. Its motor function is essential for chewing, and its sensory function provides information about touch, temperature, and pain in the lower face and oral cavity.
