DH 116 Glandular Tissues of the Head and Neck

What are the glandular tissues of the head and neck?

lacrimal

salivary

thyroid

parathyroid

thymus

What is a gland?

a structure that produces a chemical secretion necessary for normal body functioning

Exocrine gland

has a duct associated with it, the duct allows the secretion to be emptied directly into the location where the secretion is to be used

Endocrine gland

has NO duct & the secretion is emptied directly into the bloodstream

Both the endocrine & exocrine glands use ________ nerves to regulate the flow of secretion, although _________ nerves are also present.

motor

sensory

Lacrimal gland:

location & drainage

exocrine

located in the lacrimal fossa

drains into the nasolacrimal sac & then into the nasolacrimal duct, ultimately draining into the inferior nasal meatus

Lacrimal gland innervation

parasympathetic fibers of the greater petrosal nerve (7th cranial) and lacrimal nerve

Salivary glands:

Function

Controlled by

Endocrine or exocrine

cleans & lubricates, helps in digestion

controlled by autonomic nervous system

major & minor glands all exocrine

What are the major salivary glands?

parotid

submandibular

sublingual

What is the largest salivary gland & how much saliva does it produce?

parotid gland

25% of total salivary production

What type of saliva does the parotid gland produce?

serous type (more watery)

What duct is associated with the parotid gland?

Parotid duct or Stenson's duct

Parotid gland innervation

glossopharyngeal (efferent/parasympathetic) & the auriculotemporal branch of the 5th cranial (afferent)

the 7th cranial nerve travels through it but does NOT innervate it

Which salivary gland produces the most saliva?

submandibular gland (2nd largest salivary gland)

60-65% total saliva production

What type of saliva does the submandibular gland produce?

both serous & mucous types

What duct is associated with the submandibular salivary gland?

Wharton's duct

Where does the submandibular salivary gland reside?

submandibular fossa

Submandibular gland innervation

efferent parasympathetic of the chorda tympani & submandibular ganglion of the 7th cranial nerve

(motor nerve of CN 7)

Sialolith

salivary stones that may form in salivary glands & block the drainage of saliva from the duct

Ranula

major salivary glands that are blocked

Mucocele

minor salivary glands that are blocked

Xerostomia

dry mouth

can result in increased trauma to a nonprotected oral mucosa, increased cervical caries, problems in speech & mastication, & bad breath (halitosis)

What is the smallest encapsulated major salivary gland?

sublingual salivary gland

How much saliva does the sublingual salivary gland produce?

10% total salivary volume

What type of saliva does the sublingual salivary gland produce?

mixed saliva has serous & mucous, but MOSTLY mucous

What duct is associated with the sublingual salivary gland?

Bartholin's duct

Sublingual salivary gland innervation

efferent parasympathetic chorda tympani & submandibular ganglion of the 7th cranial nerve

Where are the minor salivary glands located?

all over the mouth

Are minor salivary glands exocrine or endocrine glands?

exocrine

Von Ebner glands

serous

located at the large circumvallate lingual papillae

Minor salivary glands (saliva type & innervation)

mainly mucous type with some serous

innervated by the 7th cranial nerve

What is the largest endocrine gland?

thyroid gland

What does the thyroid gland secrete and what does it do?

secretes thyroxin which stimulates the metabolic rate

What is the thyroid gland adhered to?

the trachea

A healthy thyroid _______ when swallowing.

moves

Thyroid gland is found __________ to the thyroid cartilage.

inferior

Thyroid gland innervation

sympathetic nerves of the cervical ganglia

Goiter

enlarged thyroid

What are the parathyroid glands?

four small endocrine glands located at the back of the thyroid

What does the parathyroid gland secrete & what does it do?

secretes parathyroid hormone which regulates calcium & phosphorous

Parathyroid gland innervation

sympathetic nerves of cervical ganglia

Is the thymus gland endocrine or exocrine?

endocrine

What gland is a portion of the immune system?

thymus gland

t-cell lymphocytes, mature in the thymus

What happens to the thymus gland with age?

the gland grows in size from birth to puberty, and then shrinks with age

by age 40 it is almost gone

Thymus gland innervation

vagus nerve (CN 10)