Parotid Gland
Description (size, shape, colour, function, hormones)
- paired gland
- on the side of the face
- immediately below and in front of the external ear
- main portion is
- superficial
- somewhat flattened
- quadrilateral.
Relations (superior/inferior, right/left, anterior/posterior, correlative levels)
- Anterior
- ramus of the mandible
- pterygoid and masseter muscles
- Posterior
- mastoid process
- EAM
- anterior border of sternocleidomastoid
- Superiorly
- zygomatic arch
- Inferiorly
- tapering shape
- imaginary line joining the mastoid tip to the angle of the mandible.
- Superficial surface
- covered by the superficial fascia with branches of the great auricular nerve and the lymph glands and the deep cervical fascia
- Deep surface
- one part
- lies on the digastric, styloid process and the styloid muscles
- projecting below the mastoid and SCM
- other part
- lies in front of the styloid process and posterior to the mandibular fossa behind the TM joint
- lateral to the Carotid vessels, IJV, Xth and XIth cranial nerves
- separated from the pharyngeal wall by loose connective tissue.
- one part
Other relations
- facial nerve
- courses through the parotid gland
- gives branches within the substance
- separates the gland surgically into a superficial and deep lobe
- formation of the external jugular vein in the gland
- parotid duct
- Stensen's duct
- traverses over the masseter and then through the buccinator to enter the oral cavity opposite the upper second molar at the parotid papilla
Support Structures (bones, cartilage)
- no bones or cartilage
Movement (muscles)
- no muscles
Vascular Supply (arterial supply, venous drainage, lymphatic drainage)
- external carotid artery gives the terminal branches in the gland
Innervation (Autonomic, Somatic)
- Although the facial nerve (CN VII)
- runs through the gland
- does not control the gland
- Secretion of saliva by the parotid gland is
- controlled by presynaptic parasympathetic fibres
- originating in the inferior salivatory nucleus
- these leave the brain via the glossopharyngeal nerve (CN IX)
- travel along the tympanic nerve (of Jacobson)
- pass through the tympanic plexus (located in the middle ear)
- travel in the lesser petrosal nerve until they
- reach the otic ganglion. After synapsing,
- the postganglionic fibers travel as
- part of the auriculotemporal nerve,
- a branch of the mandibular nerve (V3) to reach the parotid gland.
- Sympathetic nerves
- originating from Superior Cervical Ganglion reach the gland with blood vessels.
- stimulation leads to the production of low volume enzyme rich saliva.
- Parasympathetic stimulation
- produces a water rich mucus saliva.
- no inhibitory nerve supply to the gland.
page revision: 11, last edited: 28 Dec 2007 04:05