The auriculotemporal nerve is a sensory branch of the

mandibular nerve In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth Cranial nerves, cranial nerve (CN V). Unlike the other divisions of the trigeminal nerve (ophthalmic nerve, maxillary nerve) which ...

(CN V₃) that runs with the

superficial temporal artery In human anatomy, the superficial temporal artery is a major artery of the head. It arises from the external carotid artery when it splits into the superficial temporal artery and maxillary artery. Its pulse can be felt above the zygomatic ar ...

and vein, and provides sensory innervation to parts of the external ear, scalp, and

temporomandibular joint In anatomy, the temporomandibular joints (TMJ) are the two joints connecting the jawbone to the skull. It is a bilateral Synovial joint, synovial articulation between the temporal bone of the skull above and the condylar process of mandible be ...

. The nerve also conveys post-ganglionic parasympathetic fibres from the

otic ganglion The otic ganglion is a small parasympathetic ganglion located immediately below the foramen ovale in the infratemporal fossa and on the medial surface of the mandibular nerve. It is functionally associated with the glossopharyngeal nerve and i ...

to the

parotid gland The parotid gland is a major salivary gland in many animals. In humans, the two parotid glands are present on either side of the mouth and in front of both ears. They are the largest of the salivary glands. Each parotid is wrapped around the m ...

Structure

Origin

The auriculotemporal nerve arises from the posterior division of the mandibular nerve (CN V₃) (which is itself a branch of the trigeminal nerve (CN V)). It arises by two roots that circle around either side of the

middle meningeal artery The middle meningeal artery (') is typically the third branch of the maxillary artery#First portion, first portion of the maxillary artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum t ...

before uniting to form a single nerve.

Course

Roots of the auriculotemporal nerve circle around both sides of the

before uniting to form a single nerve. The nerve passes deep to the neck of the mandible - between it and the

sphenomandibular ligament The sphenomandibular ligament (internal lateral ligament) is one of the three ligaments of the temporomandibular joint. It is situated medially to - and generally separate from - the articular capsule of the joint. Superiorly, it is attached to th ...

- and then courses deep to the

lateral pterygoid muscle The lateral pterygoid muscle (or external pterygoid muscle) is a muscle of mastication. It has two heads. It lies superior to the medial pterygoid muscle. It is supplied by pterygoid branches of the maxillary artery, and the lateral pterygoid n ...

. It issues parotid branches and then turns superiorly, posterior to its head and moving anteriorly, gives off anterior branches to the auricle. It then crosses over the root of the zygomatic process of the temporal bone, deep to the

. Shortly after the secretomotor parasympathetic fibers branch from the auriculotemporal nerve (parotid branches) to innervate the parotid gland, the auriculotemporal nerve comprises exclusively somatosensory fibers. It ascends to reach the superficial temporal region and innervate its target structures. The auriculotemporal nerve communicates with the facial nerve (CN VII).

Parasympathetic component

Post-ganglionic parasympathetic secretomotor nerve fibres from the otic ganglion join and "hitch-hike" along the auriculotemporal nerve, leaving the nerve as it passes across the anteromedial surface of the parotid gland to enter and innervate said gland.

Distribution

The auriculotemporal nerve provides sensory innervation to the auricle,

external acoustic meatus The ear canal (external acoustic meatus, external auditory meatus, EAM) is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the auricle to the eardrum and is about in length and in diameter. Str ...

, outer side of the

tympanic membrane In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear from the middle ear. Its function is to transmit changes in pressur ...

and the skin in the temporal region (superficial temporal branches). It also carries a few articular branches that innervate the

Clinical significance

This nerve, as it courses posteriorly to the condylar head, is frequently injured in

(TMJ) surgery, causing an ipsilateral

paresthesia Paresthesia is a sensation of the skin that may feel like numbness (''hypoesthesia''), tingling, pricking, chilling, or burning. It can be temporary or Chronic condition, chronic and has many possible underlying causes. Paresthesia is usually p ...

of the auricle and skin surrounding the ear. It is the main nerve that supplies the TMJ, along with branches of the masseteric nerve and the deep temporal. After a parotidectomy, the nerves from the Auriculotemporal Nerve that previously innervated the parotid gland can reattach to the sweat glands in the same region. The result is sweating along the cheek with the consumption of foods (

Frey's syndrome Frey's syndrome (also known as Baillarger's syndrome, Dupuy's syndrome, auriculotemporal syndrome, or Frey-Baillarger syndrome) is a rare neurological disorder resulting from damage to or near the parotid glands responsible for making saliva, and ...

). Treatment involves the application of an antiperspirant or glycopyrrolate to the cheek, Jacobsen's neurectomy along the middle ear promontory, and lifting of the skin flap with the placement of a tissue barrier (harvested or cadaveric) to interrupt the misguided innervation of the sweat glands. Pain from

parotitis Parotitis is an inflammation of one or both parotid glands, the major salivary glands located on either side of the face, in humans. The parotid gland is the salivary gland most commonly affected by inflammation. Etymology From Greek παρωτῖ ...

, a condition that can be caused by

mumps MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts Gen ...

, will be carried by the auriculotemporal nerve and

great auricular nerve The great auricular nerve is a Cutaneous nerve, cutaneous (sensory) nerve of the head. It originates from the second and third spinal nerve, cervical (spinal) nerves (C2-C3) of the cervical plexus. It provides sensory innervation to the skin over ...

to the brain.

Additional images

Image:Gray178.png, Mandible of human embryo 24 mm. long. Outer aspect.

References

External links

* - "Illustration of the nerves within the

infratemporal fossa The infratemporal fossa is an irregularly shaped cavity that is a part of the skull. It is situated below and medial to the zygomatic arch. It is not fully enclosed by bone in all directions. It contains superficial muscles, including the lower ...

after removal of the

." * * () * () * http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-2.HTM {{DEFAULTSORT:Auriculotemporal Nerve Mandibular nerve