Salivary Glands And Oral Tissue Flashcards
what are the three types of oral mucosa
Lining mucosa, masticatory mucosa and specialised mucosa
What does the oral mucosa consist of
Stratified squamous epithelium, a lamina propria of dense connective tissue and a submucosa of loose connective tissue
Where is masticatory mucosa found
Covering the hard palate and gingiva
Characteristic of masticatory mucosa
It is keratinised or para-keratinised
Where is lining mucosa found
Inside of the lips, lining the buccal surfaces, covering the soft palate, covering the floor of the mouth and inner surface of the tongue
Is lining mucosa keratinised
No
Dorsum of the tongue
Keratinised epithelium and numerous papillae
Is the vermillion border of the lips keratinised
Yes
Orientations of intrinsic skeletal muscle in the tongue
Longitudinal, transverse and vertical
Epithelium of dorsum of tongue
Keratinised stratified squamous
Lamina propria of dorsum of the tongue
Dense irregular connective tissue that ties the epithelium to the underlying muscle
What are the four types of papillae
Filliform, fungiform, foliate and circumvallate
Characteristics of filiform
Conical shaped with no taste buds
Characteristics of fungiform
Blunt with taste buds
Characteristics of folite
Slit-like at the margin of the tongue with taste buds
Characteristics of circumvillate
Large, dome-shaped with a cleft surrounding them with taste buds at the margin of the papillae
What are taste buds
Multicellular chemoreceptive units that span the epithelium
What is saliva involved in
Protection, buffering, tooth integrity, antimicrobial activity, digestion and taste
What does the fluid component of saliva do
Flush away non-adhesive bacteria, debris and sugar
Function of mucins
Provide lubrication for oral tissues to move
Function of bicarbonate
Protects the teeth from bacterial acids
Function of calcium and phosphate
Helps enamel to mature and increases hardness and resistance to demineralisation
What aids in the formation and swallowing of a food bolus
Fluid and mucin components of saliva
What begins the process of breaking down food
Enzymes such as amylase
What are the 3 major salivary glands
Parotid, submandibular and sublingual
Where are the major salivary glands located
Outside the oral cavity
Where are the minor salivary glands located
In the oral mucosa - typically in the submucosa
Where do the ducts from the minor salivary glands open onto
The mucosal surface
What is the stroma of salivary glands
A tough connective tissue capsule with septa of connective tissue that subdivide the glands
What travels within the septa of salivary glands
Blood vessels, nerves and major ducts
What is the parenchyma of salivary glands composed of
Compound tuboacinar glands
What are the secretory elements of the salivary glands
Serous acini, mucous acini and mixed acini
How is secretion produced
By merocrine secretion
How does merocrine secretion occur
By exocytosis
What are the different types of duct morphology
Simple and compound
What are the different types of arrangement of secretory elements
Tuboacinar
How can glands be classified
By duct morphology and arrangement of secretory elements
What type of glands are salivary glands
Compound tuboacinar glands
Different classification of secretory elements in salivary glands
Serous and mucous
What do serous cells secrete
Thin watery secretion that contains proteins and ions
What do mucous cells secrete
Mucin which consists of a protein core that is highly decorated with sugar residues - this results in a viscous, sticky secretion
Cells of the serous acini
Wedge shaped with a prominent nucleus in the basal part of the cell
Have extensive rER and a granular appearance due to the apical secretory vesicles
Cells of the mucous acini
Found in the tubular element of the tuboacinar glandular structure
Have large number of secretory granules packing the cytoplasm
What happens to the nucleus in routine staining
Typically pushed to the basal surface of the cell by granules
What is a serous demilune
An artifact present in staining
What do the population of epithelial cells surrounding the secretory cells of salivary glands do
Contract
What does the acinus empty into
Intercalated duct
Intercalated duct epithelium
Simple cuboidal
What does the intercalated duct empty into
Striated duct
Cells of striated duct
Columnar with their nucleus in a central position and have prominent striations at the basal surface
What are the striations within a striated duct
Infoldings of the cell membrane accompanied by lines of mitochondria
Why do striated ducts require mitochondria
To power the molecular pumps
What cells do striated ducts pump out/in
Na+ ~ out
K+ and HCO-3 ~ in
What is the net effect of ions being taken out/added into the saliva
A hypotonic saliva
What are both intercalated and striated ducts
Interlobular
What do striated ducts empty into
Secretory ducts
Where are secretory ducts found
Within the connective tissue
Lining of secretory ducts
Pseudostratified columnar epithelium with tall columnar cells and small basal cells
Function of the small basal cells
Stem cells
Lining of merged duct
Stratified squamous epithelium
What is the main form of minor salivary glands
Mucous
Examples of minor secretory glands
Lingual, minor sublingual, labial, palatine and buccal
What are the entirely serous minor glands
Von Ebners glands
Where are von Ebner’s glands found
Associated with circumvillate and foliate papillae and open into the cleft
What is the function of the secretion from von Ebner’s
Help to dissolve food molecules to aid taste and also keep the cleft flushed to allow for the next taste
