Salivary Glands Overview

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Questions and Answers

What is the function of the Parotid gland in saliva production?

Produces serous saliva exclusively (correct)

Contributes primarily to saliva composition without production

Produces salivary enzymes only

Produces primarily mucous saliva

Where is the Parotid gland located?

In front of the uvula

Above the mandible

Between the maxilla and zygomatic arch

Below the external auditory meatus (correct)

Which duct is associated with the Parotid gland?

Ductus submandibularis

Wharton's duct

Sublingual duct

Stensen's duct (correct)

Which type of saliva is produced by the major salivary glands?

A combination of serous and mucous saliva Signup and view all the answers

What percentage of total salivary volume is produced by the major salivary glands?

90% Signup and view all the answers

What type of secretion is produced by serous acini?

Watery serous secretion Signup and view all the answers

Which of the following is a function of mucous saliva?

Binding food into a bolus Signup and view all the answers

What distinguishes myoepithelial cells in the acini?

They contract and squeeze to force saliva out Signup and view all the answers

Which type of duct is lined by a single layer of cuboidal epithelial cells?

Intercalated duct Signup and view all the answers

What is NOT a component of the acinar fluid before it becomes saliva?

Enzymes Signup and view all the answers

Which nerve is responsible for the autonomic innervation of the glossopharyngeal gland?

Glossopharyngeal Signup and view all the answers

What percentage of total saliva volume is produced by the submandibular gland?

60-65% Signup and view all the answers

Wharton’s duct opens in which anatomical location?

Under the tongue, at the sublingual caruncle Signup and view all the answers

Which of the following glands produces predominantly mucous saliva?

Sublingual gland Signup and view all the answers

Which gland is smallest among the major salivary glands?

Sublingual Signup and view all the answers

What function do the Tubarial glands potentially serve?

Lubrication of the nasopharynx and oropharynx Signup and view all the answers

Which structure is responsible for producing and lining the ducts of salivary glands?

Adenomere Signup and view all the answers

What type of saliva do minor salivary glands predominantly produce?

Mixed saliva, predominately mucous Signup and view all the answers

What type of epithelium lines the secretory duct of the salivary glands?

Pseudostratified columnar epithelium Signup and view all the answers

Which artery supplies blood to the salivary glands?

External carotid artery Signup and view all the answers

What is a common cause of hyposalivation?

Autoimmune diseases Signup and view all the answers

Which type of cyst is associated with trauma to the salivary gland?

Mucocele Signup and view all the answers

What triggers the salivary nuclei in the brain?

Taste, smells, and thoughts Signup and view all the answers

Which salivary gland condition is characterized by the formation of calcium deposits?

Sialolithiasis Signup and view all the answers

What is xerostomia primarily caused by following head and neck irradiation?

Atrophy of secretory cells Signup and view all the answers

What type of epithelial cells are primarily involved in the modification of saliva?

Columnar epithelial cells with basal striations Signup and view all the answers

Which of the following is NOT a known cause of dry mouth?

Post-nasal drip Signup and view all the answers

What type of salivary gland tumor is known for being bilateral?

Warthin’s tumor Signup and view all the answers

Which medication type is commonly associated with contributing to dry mouth?

Antidepressants Signup and view all the answers

Which salivary gland is responsible for producing the largest percentage of saliva volume?

Parotid gland Signup and view all the answers

What is the primary function of the salivary glands?

To aid in digestion through enzyme secretion Signup and view all the answers

Which of the following conditions can NOT impact salivary gland function?

Skin infections Signup and view all the answers

In addition to moisture production, what role does saliva play in oral health?

Maintaining acid-base balance Signup and view all the answers

Which type of carcinoma is characterized by its acinic cell type?

Acinic cell carcinoma Signup and view all the answers

Study Notes

Salivary Glands

There are three bilateral pairs of major salivary glands: parotid glands, submandibular glands, and sublingual glands.
They produce 90% of the total salivary volume.

Parotid Gland

Largest of the major glands.
Produces 100% serous saliva and 25% of total saliva volume.
Located below the external auditory meatus, between the mastoid process and the posterior border of the ramus.
Parotid duct (Stensen's duct) is 5cm long and runs from the gland outside the masseter muscle parallel to, and 1cm below, the zygomatic arch.
Pierces the buccinator muscle to open into the oral cavity via the Stensen's papillae.
Innervated by the glossopharyngeal (autonomic), auriculotemporal (sensory) and facial nerves.

Submandibular Gland

Produces mixed saliva secretions (both serous and mucous).
Half the size of the parotid gland.
Produces 60-65% of total saliva volume.
Located between the body of the mandible and the mylohyoid muscle, in the submandibular fossa.
Submandibular duct (Wharton's duct) is 5 cm long and opens under the anterior part of the tongue, lateral to the lingual fraenum at the sublingual caruncle.
Innervated by the chorda tympani and lingual branch of the inferior dental nerve.

Sublingual Gland

Produces 60% mucous saliva.
Smallest of the major salivary glands.
Produces 5-10% of total saliva volume.
Located on the floor of the mouth in the sublingual fossa.
Sublingual ducts (Bartholin's duct, and 10-20 smaller Rivinus ducts) open along the sublingual fold.
Innervated by the same nerves as the submandibular gland.

Tubarial Glands

Located in the nasopharynx.
May contain a large number of seromucous acini, playing a role in nasopharynx/oropharynx lubrication and swallowing.

Minor Salivary Glands

Produce mixed saliva, predominately mucous.
Produce lots of salivary proteins.
Produce >10% of the total saliva volume.
Named according to where they are found e.g., buccal or labial salivary glands.

Salivary Gland Structure

Composed of epithelium, connective tissue, and adenomeres.
The capsule and septa carry the nerve and blood supply to the cells.
Adenomeres are the working part of the salivary gland and are surrounded by connective tissue.

Acini

Secretory units within the adenomere.
Made up of secretory cells and classified into: mucous acini, serous acini, or a mixture of both.

Serous Acini

Composed of serous secretory cells.
Produce a watery serous secretion (serous saliva).
Function in lubricating food, initiating enzymatic digestion, removing epithelial debris, and diluting food.

Mucous Acini

Composed of mucous secretory cells.
Have a wider lumen.
Produce a viscous mucin-rich secretion (mucous saliva).
Function in binding food into a bolus, protecting the oral cavity against frictional abrasion, and lubrication.

Serous-mucous Acini

In a mixed serous-mucous acini, the serous secretory cells form a serous demilune around the mucous secretory cells.

Myoepithelial Cells

Embrace acini secretory cells, contracting and squeezing to force saliva out of the lumen and into the ducts.

Acinar Fluid

Consists of: water, inorganic ions, small molecules, and products synthesized by cells (mucoproteins and amylase).

Ducts

Are located following the secretory end piece and modify the saliva via resorption.
Three types of ducts: intercalated, striated, and excretory.

Intercalated Ducts

Lined by a single layer of cuboidal epithelial cells.

Striated Ducts

Make up the bulk of the duct system.
Lined with a single layer of columnar epithelial cells characterized by basal striations.
Aid in the modification of saliva.

Excretory (Terminal) Ducts

Also called the secretory duct.
Saliva exits into the oral cavity via this duct.
Lined by pseudostratified columnar epithelium which changes to stratified cuboidal and then finally stratified squamous epithelium at its opening.

Blood Supply

Supplied by the external carotid artery (plus facial and lingual artery), with vessels (and nerves) entering the gland at the hilum.
There are two capillary networks, one for the secretory end piece and one for the ducts.

Control of Salivation

Salivary nuclei in the brain are stimulated by taste, smells, thoughts, etc.
This triggers neurotransmitter release from nerve endings of salivary glands.

Disorders of the Salivary Glands

Hyposalivation

Can be caused by medications/tablets, radiotherapy, autoimmune diseases, diabetes, and salivary stones.

Obstruction

Caniculi: calcium deposits formation in the ducts, common in the submandibular glands.
Cysts: trauma to the salivary gland or duct causing accumulation of saliva in the surrounding tissue. Mucocele - minor glands; Ranula - major glands in the floor of the mouth (could be submandibular or sublingual).

Irradiation

Head and neck irradiation destroys the secretory cells (atrophy) and leads to xerostomia.

Functional Disorders

Dry mouth caused by emotional disturbances (e.g., anxiety), mouth breathing, smoking, and drugs.

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Description

This quiz explores the anatomy and function of the major salivary glands, including the parotid, submandibular, and sublingual glands. Learn about their locations, types of saliva produced, and the innervation of the parotid gland. Test your knowledge on these important components of the human salivary system.