The parotid gland is the largest of the three major paired salivary glands. It is a predominantly serous salivary gland located on either side of the face, mainly in the region between the ear and the angle of the mandible.
The three major salivary glands are:
* Parotid gland – mainly serous
* Submandibular gland – mixed, predominantly serous
* Sublingual gland – mixed, predominantly mucous
The parotid gland is clinically important because the facial nerve passes through the gland and divides into its terminal branches within it.
Location of the Parotid Gland
The parotid gland lies in the parotid region, below and in front of the external ear.
It extends approximately from the region around the zygomatic arch superiorly to the angle of the mandible inferiorly.
The gland is related to the:
* Ramus of the mandible
* Mastoid process
* Styloid process
* External ear region
The gland is enclosed by a tough parotid fascia, which contributes to its capsule.
Parts of the Parotid Gland
The parotid gland is commonly described as having:
* Superficial part
* Deep part
The facial nerve passes between these parts and forms a plexus within the gland.
High-yield point: The facial nerve divides the parotid gland into superficial and deep parts anatomically, but it does not provide the secretomotor supply of the gland.
Structures Passing Through the Parotid Gland
Three important structures pass through the parotid gland.
From superficial to deep, remember:
Nerve → Vein → Artery
Facial nerve → Retromandibular vein → External carotid artery
This is one of the most important relationships to remember for exams.
Facial Nerve
The facial nerve enters the parotid gland after emerging from the stylomastoid foramen.
Inside the gland, it forms the parotid plexus and divides into terminal branches.
Retromandibular Vein
The retromandibular vein is formed within the parotid gland by the union of:
* Superficial temporal vein
* Maxillary vein
External Carotid Artery
The external carotid artery enters the gland and terminates within it by dividing into:
* Superficial temporal artery
* Maxillary artery
Parotid Duct
The parotid duct is also called the Stensen duct.
It emerges from the anterior border of the parotid gland and runs forward across the lateral surface of the masseter muscle.
It then turns medially, pierces the buccinator muscle, and opens into the oral cavity opposite the maxillary second molar tooth.
⭐ Exam Point
Parotid duct opens opposite the upper second molar tooth.
Blood Supply
The parotid gland receives arterial blood mainly from branches of the external carotid artery, including the superficial temporal and transverse facial arteries.
Venous Drainage
Venous blood from the gland drains mainly through the retromandibular vein and its tributaries.
Lymphatic Drainage
Lymph from the parotid region drains mainly into:
* Parotid/preauricular lymph nodes
* Upper deep cervical lymph nodes
Nerve Supply of the Parotid Gland
The nerve supply is an important FMGE/NEET-PG topic.
The facial nerve passes through the parotid gland, but it does not provide its secretomotor supply.
Parasympathetic Secretomotor Pathway
Glossopharyngeal nerve (CN IX)
↓
Tympanic branch
↓
Tympanic plexus
↓
Lesser petrosal nerve
↓
Otic ganglion
↓
Auriculotemporal nerve (V3)
↓
Parotid gland
⭐ Most Important Point
CN IX provides the parasympathetic secretomotor fibers to the parotid gland.
The auriculotemporal nerve carries the postganglionic parasympathetic fibers to the gland.
Facial Nerve and Parotid Gland
The facial nerve emerges from the skull through the stylomastoid foramen.
It then enters the parotid gland and forms the parotid plexus.
It divides into two major divisions:
* Temporofacial division
* Cervicofacial division
These give rise to the five terminal branches of the facial nerve.
Why Is the Facial Nerve Important in Parotid Surgery?
The facial nerve passes through the parotid gland.
Therefore, parotid surgery requires careful identification and preservation of the facial nerve.
Damage to the nerve or its branches can cause weakness or paralysis of muscles of facial expression.
Clinical Anatomy
1. Parotitis
Parotitis refers to inflammation of the parotid gland.
It can occur because of infectious or non-infectious causes.
A classic infectious cause is mumps, caused by the mumps virus.
Parotitis may cause:
* Painful swelling near the ear
* Facial swelling
* Difficulty chewing
* Pain during eating
2. Parotid Tumors
The parotid gland is a common site for salivary gland tumors.
Pleomorphic adenoma is the most common benign salivary gland tumor.
A parotid mass accompanied by facial nerve weakness is concerning for malignant involvement because the facial nerve runs through the gland.
3. Frey Syndrome
Frey syndrome is an important complication that can occur after parotid surgery or trauma.
It results from abnormal regeneration of autonomic nerve fibers.
Patients may develop:
* Facial flushing
* Sweating
* Warmth over the preauricular region
These symptoms occur particularly during eating.
Medical Disclaimer: The information provided in this article is strictly for educational, study, and exam-preparation purposes. It does not constitute professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for clinical decisions.
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