Salivary Gland - Anatomy

Question 1

With what other organs do the salivary glands share the same embryologic origin?

Answer 1

Liver, gallbladder, and pancreas (all come from mesodermal buds of the foregut).

Question 2

When does the parotid gland encase the facial nerve?

Answer 2

Third month gestation.

Question 3

What are the boundaries of the parotid comparunent?

Answer 3

Superiorly, the zygoma; posteriorly, the external auditory canal;
anteriorly, the masseter muscle;
inferiorly, the
styloid process, carotid artery, jugular vessels, and styloid muscles.

Question 4

Where does Stenson’s duct arise from in relation to the zygoma?

Answer 4

1.5 em inferior to the zygoma.

Question 5

What muscle does Stenson’s duct pierce?

Answer 5

Buccinator.

Question 6

Where does Stenson’s duct open intraorally?

Answer 6

Just opposite the 2nd upper molar.

Question 7

What branch of the facial nerve travels with Stenson’s duct?

Answer 7

Buccal

Question 8

What membrane separates the parotid gland from the submandibular gland?

Answer 8

Stylomandibular membrane

Question 9

How does the saliva produced from the parotid gland differ from that of the sublingual gland?

Answer 9

The saliva from the parotid gland is serous, high in enzymes, and low in mucin; that from the sublingual gland is
primarily composed of mucin.

Question 10

What is the blood supply to the parotid gland?

Answer 10

Transverse facial artery, a branch of the superficial temporal artery.

Question 11

What is the major venous drainage of the parotid gland?

Answer 11

Posterior facial vein.

Question 12

What is unique about the lymphatic drainage of the parotid gland?

Answer 12

The lymph nodes are contained within the gland, and it is the only salivary gland with two layers of lymph nodes.

Question 13

Which layer of lymph nodes has the most nodes (superficial or deep)?

Answer 13

Superfacial

Question 14

Describe the pathway of parasympathetic innervation to the parotid gland.

Answer 14

Preganglionic parasympathetic fibers leave the inferior salivatory nucleus via the glossopharyngeal nerve, pass
through the jugular foramen, travel through the middle ear (as Jacobson’s nerve), and then travel along the floor of
the middle cranial fossa (as the lesser petrosal nerve) to the otic ganglion; postganglionic parasympathetic fibers
leave the otic ganglion via the auriculotemporal branch ofV3 and travel to the parotid gland.

Question 15

Where does the retromandibular vein lie in relation to the facial nerve?

Answer 15

In most people, it courses deep to both trunks of the facial nerve. In up to 10% of people, the vein crosses either trunk laterally.

Question 16

Which lymph nodes drain tumors from the parotid gland?

Answer 16

Nodes just inferior to the gland adjacent to the sternocleidomastoid muscle and the external jugular vein.

Question 17

What muscle separates the submandibular gland into a superficial and deep lobe~

Answer 17

Mylohyoid.

Question 18

Where do the hypoglossal nerve and lingual nerve lie in relation to Wharton’s duct as it exits the submandibular gland?

Answer 18

Hypoglossal nerve lies inferiorly and lingual nerve lies superiorly.

Question 19

Which vein can be ligated and retracted superiorly during submandibular gland excision to protect the marginal mandibular branch of the facial nerve?

Answer 19

Anterior facial vein.

Question 20

What duct(s) drain the sublingual gland?

Answer 20

Typically there are about 10 ducts of Rivinus that drain the gland but occasionally several of these small ducts may
join to form a larger sublingual/Bartholin’s duct.

Question 21

What component of saliva agglutinates bacteria and activates autolysins?

Answer 21

Lysozyme.

Question 22

What is the role of salivary peroxidase?

Answer 22

Helps breakdown salivary thiocyanate into products that interfere with bacterial cell metabolism.

Question 23

What is the secretory potential

Answer 23

Hyperpolarization of acinar cells upon stimulation by the autonomic nervous system.

Question 24

What happens to the composition of saliva as it moves from the acinar cell (primary secretion) through the duct?

Answer 24

It loses sodium, acquires potassium, and becomes increasingly hypotonic. The degree of modification depends on the salivary flow rate, with higher rates producing saliva closer in composition to the primary secretion.

Question 25

True/False: Only muscarinic acetylcholine receptors are incolved in salivary gland stimulation.

Answer 25

true

Question 26

Which salivary glands contribute the highest % of resting/unstimulated saliva output?

Answer 26

submandibular

Question 27

Which salivary glands contribute the highest % of stimulated saliva output?

Answer 27

Parotid gland