Salivary Glands And Composition Flashcards
What are 3 components of saliva for lubrication
Mucins
Proline rich glycoproteins
Water
What are 2 compositions of saliva for speech
Water
Mucins
What are 2 compositions of saliva for taste
Water
Gustin
What are 6 compositions of saliva for buffering bicarbonate
Bicarbonate
Phosphate ions
Proteins
Calcium
Phosphate
Statherin
What are 4 compositions of saliva for anti microbial properties
Amylase
Lysozyme
Lactoferrin
Secretory igA
What is the parotid duct also known as
Stensons
What is the submandibular duct also known as
Whartons
What is the sublingual duct also known as
Bartholins
What is the blood supply for the parotid gland
External carotid artery
What is the parasympathetic nerve supply for the parotid gland
Glossopharyngeal
What is the sympathetic innervation of the parotid gland
Superior cervical ganglion
Where does the submandibular duct open
Lateral to the lingual frenulum
What is the blood supply for the submandibular gland
Facial and lingual arteries
What is the parasympathetic supply for the submandibular gland
Facial nerve
What is the name of the small ducts of the sublingual gland
Ducts of rivinus
Where does the sublingual duct open
With the submandibular duct at the sublingual caruncle
What is the blood supply of the sublingual gland
Sublingual and submental arteries
What is the innervation of the sublingual gland
Facial nerve
How many minor salivary glands are there
600 - 1000
Where are the minor salivary glands NOT found
In the gingiva and anterior hard palate
What type of saliva does the parotid gland produce
A serous watery secretion
What type of saliva does the submandibular gland produce
A mixed serous and mucous secretion
What type of saliva does the sublingual gland produce
Predominantly mucous in character
What are the 2 basic types of acinar epithelial cells
Serous cells
Mucous cells
What do serous cells do
Secrete a watery fluid essentially devoid of mucus
What do mucous cells do
Produce a very mucus rich secretion
What are the 5 secretory unit components
Acinus
Myoepithelial cells
Intercalated duct
Striated duct
Excretory duct
Where are the acinus
At the base of the gland composed of acinar cells surrounded by Myoepithelial cells
What is the intercalated duct
The first part of the duct which serves as the conduit from the acini to the striated duct
What does the striated duct contain
Cells that are mitochondria rich and participate in Na+ and Cl- reabsorption, K+ and HCO3- secretion
What comes after the striated duct
The saliva reaches the excretory duct before exiting the gland
How do striated ducts appear
Large simple columnar clear pink cells with large nuclei
How do intercalated ducts appear
Narrower with smaller cytoplasm stratified cuboidal
How do excretory ducts appear
Large lumen wall ratios with simple columnar epithelial linings
What is the venous drainage for the parotid gland
Via the retromandibular vein
What is the venous drainage of the submandibular gland
Facial vein - into the internal jugular vein
Sublingual vein - into lingual vein then internal jugular vein
What is the venous drainage of the sublingual gland
Sublingual and submental veins into the lingual and facial veins then into the internal jugular vein
What type of saliva is produced after the striated duct
Hypotonic fluid
What is the primary stage of salivary secretion
Containing amylase and electrolytes is produced in the acinar cell
What is the normal flow rate of unstimulated saliva
Above 0.1ml/min
What is the percentage for average daily stimulated saliva production
80% - 90%
What is the unstimulated flow of parotid gland
20% of daily salivary flow serous
What is the unstimulated flow of submandibular gland
65% of daily salivary flow serous and mucinous
What is the unstimulated flow for the sublingual glands
10% of daily salivary flow mucinous
What is the unstimulated flow of minor glands
Up to 5% of daily salivary flow
What is the composition of saliva
99% water
1% exfoliated epithelial cells, proteins, electrolytes
What happens when there is an increase of bicarbonate in saliva
This increases the pH
What is the main buffering component of saliva
Bicarbonate
Why would there be a drop in pH in saliva
Caused by H+ from lactic acid produced by bacteria
Where is HCO3- produced for saliva
Secreted in the acinus all the time and also in the striated saliva ducts when saliva is stimulated
What does the enamel pellicle act as
A diffusion barrier slowing both attacks by bacterial acids and loss of dissolved calcium and phosphate ions
What types of proteins are in the enamel pellicle
Proline rich proteins (PRPs)
What 3 chemicals are present in the remineralisation process
Calcium
Trivalent phosphate
Hydroxyl ions
What are the 4 main salivary proteins
Statherin
PRPs
Cystatins
Histatins
Which 2 proteins come from the acinar
Statherin
Proline rich proteins (PRPs)
What percentage of all proteins in saliva are PRPs
25-30%
What do salivary proteins do
Bind free calcium
Absorb to hydroxyapatite surfaces, inhibit crystal growth and regulate hydroxyapatite crystal structure
What are the 5 main actions of Statherin
Potent inhibitor of crystal growth
High affinity for hydroxyapatite and calcium phosphate minerals
Maintains the appropriate mineral solution dynamics of enamel
Inhibits spontaneous precipitation of calcium phosphate salts from supersaturated saliva
Help with transport of calcium and phosphate transport during secretion of saliva
How do inhibitors encourage mineralisation
By preventing crystal growth on the surface of lesion by keeping pores open
How is saliva cleansing
Pushes noxious agents to the gut
Washes away bacterial aggregates
Removal of food debris
Every 3 hours surface layer of cells replaced and removed
What is the main immunoglobulin in saliva
Secretory IgA
What percentage of salivary antibodies is secretory IgA
90-98%
What does secretory IgA do
Limit microbial adherence and agglutinates (sticks together) bacteria
Has some antiviral properties
How much IgA is derived from GCF
1-10%
What does lysozyme, lactoferrin do
Breaks down bacterial walls
What is lactoferrin
An iron binding protein - trace amounts needed for bacteria metabolism, inhibits their growth works alongside lysozyme to help burst bacterial walls
What do Mucins do
Aggregate bacterial cells unable to attach to surfaces swallowed
What inhibits Candida albicans
Histatins
What are the 3 alpha and beta defensins in saliva
Neutrophil
Granulocytes
Mucosal cells
What do defensins do
Integrate into lipid bilayer and cause membrane leakage and rupture
Some antifungal properties possibly by binding to surface proteins
Where are mucous glycoproteins formed
In acinar cells
What does initial digestion of starch turn into
Salivary amylase
Where is salivary amylase mainly secreted from
The parotid glands where flow increases on eating
As saliva travels down the duct what is removed
The sodium chloride and bicarbonate
What happens to saliva when we are dehydrated
Salivary flow decrease stimulating thirst
How does wound healing with saliva occur
Salivary epidermal growth factor stimulates cell proliferation followed by differentiation and regeneration
Histatin plays a role in cell migration
What is the medical condition for dry mouth
Xerostomia
