Salivary glands are compound exocrine glands composed of both secretory and ductal components. There are three major salivary glands - parotid, submandibular, and sublingual glands. Saliva produced contains water, electrolytes, enzymes, mucins and other proteins that serve protective, digestive and antimicrobial functions in the oral cavity. The glands have both serous and mucous acini that secrete into a ductal system ranging from intercalated to striated to excretory ducts. With aging, the glands demonstrate loss of parenchyma and increased fibrous tissue.

2. Salivary glands are compound , tubulacinar ,
merocrine and exocrine gland
Compound: means it has more than one tubule
entering the main duct.
Tubulacinar: means the morphology of the
secreting cell
Merocrine: means that only the secretion of the
cell is released
Excorine: means gland secretes fluid onto a free
surface

4. *Is a complex fluid , produced by salivary gland,
the most important function is to maintain the
well-being of the mouth.
*In human, three pairs of major SG are located
outside the O.C with extended duct which
open into the mouth, and numerous minor SG
which located in the submucosal layer with
short ducts that open directly onto mucosal
.surface

5. It contains over than 99% of water, inorganic and
organic compounds ( prtn, glycoprtn,
enzymes).
Mucin= acts as lubricant during mastication
Lysozyme= antibacterial substance
Epidermal growth factor= produced by
submandibular gland involved in wound
healing
Amylase = digest food.

6. - Kalikernin : enezyme capable of cleaving peptide
bond in prtn (blood coagulation).
- Histatin: prevents fungal infection.
- Lipase: initiate digestion of fat.
- Lactoperoxidase: stimulation of activity of minor
salivary gland.
- Mucin: lubricant and preserve mucosal integrity.
- Proline rich prtn: present in enamel pelllicl.
- Cystatin: prevent crytal growth of Ca and
phosphat.

7. Composition of Saliva
PARAMETER CHARACTERISTICS
Volume: 600-1000 mL/day
-Electrolytes: Na+, K+, Cl–, HCO3−, Ca2+, Mg2+, HSCN–, and F
Peptides : Amylase, proline-rich prtn, mucins, histatin, cystatin ,Secretory proteins/
lysozyme, lactoferrin,defensins andcathelicidin-LL37
Immunoglobulins: Secretory immunoglobulin A;
Small organic: Glucose, amino acids, urea, uric acid, and lipid molecules
adenosine monophosphate-bindingOther components: Epidermal growth ,
proteins, and serum albumin
FLOW RATE
(ML/MIN) WHOLE PAROTID SUBMANDIBULAR
Resting 0.2-0.4 0.04 0.1
Stimulated 2.0-5.0 1.0-2.0 0.8
pH 6.7-7.4 6.0-7.8,

8. The average person
produces
approximately 0.5 L –
1.5 L per day
•Salivary flow peaks in
the afternoon
•Salivary flow decreases
at night.
•There is a difference in
the quality between
stimulated and
unstimulated saliva

9. * Parotid secret a watery saliva rich in enzymes
such as amylase, prtn such as proline-rich prtn,
and glycoprtn.
* Submandibular in addition to the above it
contains highly glycosylated substance Mucin.
*Sublingual produce a viscous saliva rich in
mucin.
*Oral fluid includes the secretion of MSG, MiSG,
desqumated epith., MO, food debris and serum
and inflammatory cells.

10. Effect Active Constituent
Protection Lubrication, lavage, pellicle
formation
Glycoprotein
Water
Buffering Action Regulates pH Phosphate and
Bicarbonate
Digestion Digests starch
Digests lipids
Bolus formation
Amylase
Lingual Lipase
Facilitation of Taste Taste bud growth and
maturation, dissolves
substances to carry to taste
buds
Gustin
Defensive Action Against
Microbes
Antibodies
Hostile Environment
Lysozyme
Lactoferrin
IgA
Ionic Exchange Between
Tooth Surface
Posteruptive Maturation of
Enamel
Repair
Calcium
Phosphate

11. Functions of Saliva
FUNCTION EFFECT ACTIVE
CONSTITUENTS
Protection Clearance Water
Lubrication Mucins, glycoproteins
Thermal/chemical insulation Mucins
pellicle formation Proteins, glycoproteins,
mucins
Tannin binding basic proline-rich proteins,
histatins
Buffering pH maintenance Bicarbonate, phosphate, basic proteins, urea,
ammonia
Neutralization of acids
Tooth integrity Enamel maturation, repair Ca, PO4, F, statherin, acidic proline-rich
proteinsAntimicrobial
activity
physical barrier Mucins
Immune defense Secretory immunoglobulin A
Nonimmune defense Peroxidase, lysozyme, lactoferrin,
histatin, mucins, agglutinins, secretory leukocyte protease inhibitor, defensins and cathelicidin-LL37
Tissue repair Wound healing, epithelial regeneration Growth factors, trefoil prtn
Digestion Bolus formation Water, mucins
Starch,triglyceride digestion Amylase, lipase
Taste Solution of molecules Water and lipocalins
Maintenance of taste buds Epidermal growth factor and carbonic
anhydrase VIf

12. - It is the largest gland
- Superficial portion lies
subcutanously infront of
ear
- Deep portion behind the
ramus of mandible
-wt = 14-28 g
- Contains facial nerve
- Stensons duct which open
infront of 2nd molar
- Supplied from ECA
PAROTID

13. - Post part of floor of
mouth
- Wt = 10-15 g
- warton’s duct which
opens beneath the
tongue
- Supplied from facial
and lingual artries

14. - Wt = 2 g
- Ant part of floor of
mouth
- Ducts fo rivinis which
opens into Bartholin
duct
- Blood supply from
submental and
sublingual artries

15. Minor salivary glands are found
throughout the mouth:
– Lips
– Buccal mucosa (cheeks)
– Alveolar mucosa (palate)
– Tongue dorsum and ventrum
– Floor of the mouth
Together, they play a large role in
salivary production.
Not present in gingivae and
dorsum of anterior 2/3 of
the tongue

16. PRIMORDIA TIME OF
DEVELOPME
NT
EMBRYONIC
ORIGIN
REGION
Parotid gland
primordia
(anlage)
5th to 6th week Ectoderm Labiogingival
sulcus
Submandibular
gland
primordia
6th week Endoderm Hyoid arch
Sublingual
gland
primordia
7th to 8th week Endoderm Linguogingival
sulcus
Intraoral minor
salivary glands
3rd month

17. STAGE 1 ;- FORMATION
INDUCTION OF ORAL
EPITHELIUM BY UNDERLYING
MESENCHYME .
STAGE 2 ;- FORMATION
&GROWTH OF THE
EPITHELIAL CORD.

18. STAGE 3. INITIATION OF BRANCHING
IN TERMINAL PARTS OF THE
EPITHELIAL CORD
& CONTINUATION OF GLANDULAR
DIFFERENTIATION .
STAGE 4. REPETITIVE BRANCHING
OF THE EPITHELIAL CORD
&LOBULE FORMATION

19. STAGE 5 ;-CANALIZATION OF
PRESUMPTIVE DUCTS
STAGE 6. ;-
CYTODIFFERENTIATION

20. *Each salivary glands
Consist of two main
elements:
- Glandular secretory tissue (
parenchyma)
- Supporting connective
tissue ( stroma)
- from the stroma of
capsule pass septa that
divide the gland into
major lobes which further
divide into lobules

21. *A grape-like cluster of parenchymal cells around a
lumen
* Types
- Serous
- Mucous
- Mixed (Serous Demilunes capping mucous cells)
*Myoepithelial cells around the acini
- Contractile cells with several processes
- Synonyms: basket cells

22. * Intra-lobular
- Acinus Lumen
- Intercalated ducts
- Striated Duct
* In intra-lobular system,
- Plazma cells in stroma
- Electrolytes
- Epidermal GF (produced and secreted by the
submandibular salivary gland) and Kallikrein.
* Inter-lobular
* Collecting Ducts
- the inter-lobular system is inert, does not affect the
composition

23. * Connective Tissue
* Mesenchymal Origin
* Macro-to-microscopic levels
- Capsular
- Inter-Lobar
- Inter-Lobular
- Inter-acinous
* Capsular, inter-lobar and inter-lobular septa contain blood vessels
and nerves
* Constituents
- Collagen Fibers
- Fibroblasts
- Fat Cells
* With age there is decrease in parenchyma and an increase
in stroma (esp. fat cells)

24. Parenchyma
•Epithelial cells
containing secretory
granules
Stroma
Duct

25. SEROUS MUCOUS

26. *The acinus via its lumen
empties into and
intercalated duct lined
with cuboidal
epithelium , which in
turn joins a larger
striated duct formed of
columnar cells
- Both are intralobular
and affect the secretion
of passing through
them

27. - Plasma cells ( which
secrete the IG) are found
in the stroma of the
gland around the
intralobular ducts.
- Striated duct empty into
inert collecting duct
which carry the saliva to
mucosal surface and
may be lined near their
termination by a layer of
stratified squamous
epithelial cell.
- The collecting duct are
interlobular.
- The connective tissue
septa carry the blood
and nerve into
parenchym.

28. Intralobular
ExcretoryStriatedIntercalated
Interlobular

31. Pear-shaped groups of
epithelial cells with
distinct basement
membrane
Dense cytoplasm
Round, central nucleus
Zymogen granules are
present
Myoepithelial cells between
epithelium and basement
membrane of acini

32. - Spherical shaped consist of 8-12
cells
- Base to connective tisse and apex to
lumen
- Nucleus in the basal part
- Secretory granules which is rich in
macromolecules in apical
cytoplasm.
- Basa, l cytoplasm contains RER,
golgi complex, mitochondria
lysosomes
- Plasma membrane contains
intercellular canalliuli w short
microvilli.
-Lateral surface has interdigitated
folds to increase surface area .
--it is joined by tight junction ,
adhereing junciton and
desomsomes

33. Larger than serous acini
Abundant cytoplasm
filled with clear mucus
Pyramidal cells with
flattened basal nuclei
Myoepithelial cells
between epithelium
and basement
membrane of acini
Presence of mucigen
granules

34. Tubular configuration
Central lumen larger than
serous
Has serous demilune
covering its ends
-Apical cytoplasm contains
mucin which compress
and flatten the nuclues
-Large golgi complex basal
to secretory granules
-- lack of intercellular
canalliculi except in the
demilune end

35. Thin watery secretion
Zymogen granules
Nucleus: Round, central
Lumen: Small
Darkly stained
Enzyme action
Indistinct cell boundaries
Eg: Parotid gland
Thick viscous secretion
Mucigen granules
Flat, peripheral
Lumen: large
Lightly stained
Protection and lubrication
Distinct cell boundaries
Eg: Sublingual gland
Mucus acinus

36. MYOEPITHELIAL CELLS:
Flat, indistinct cells with
long cytoplasmic
processes that aid in
contraction
Lie between epithelial cells
and basal lamina of the
acini where they are
well-developed and
branched
Called “basket cells”
around the acini
ME also found around
intercalated ducts but
are more spindled

37. - Contractile cells around
serous and intercalated
duct.
- From epithilial origin
located between basal
lamina and duct cells
which linked to them by
desosomes.
- Around the secretory end it
is stellate shape
- Its organlles located
perinuclear in cytoplasm
- Around intercalated duct it
is fusiform shape.
- Contraction around
secretory portion help
to support the acini
during active secretion
- Also help into emptying
the content
-Around intercalated
duct it wide and
shorted the duct help to
maintain its patency.

38. - it contains cytokeratin
intermediate filament
and contractile actin
filaments, which can be
used to help identify
them using
Immunocytochemistry
-

40. 40
Secretions pass through a system of ducts
Smallest – intercalated ducts lined by
flattened cells
Intercalated ducts open into striated ducts
lined by cuboidal cells
Striated ducts open into excretory ducts
lined by simple columnar epithelium

41. Classified as intralobular
duct
Cuboidal epithelial cells
Smallest branch of the
system of ducts
Prominent in Salivary
Glands

42. Centrally placed nuclei and
small amount of
cytoplasm containing
EPR, and a small glogi
complex.
A few small secretory
granules may be found
in apical cytoplasm.
In parotid, they are long,
narrow, and branching

43. Formed by union of
intercalated duct
Columnar cell with
centrally placed nucleus
and pale acidophillic
cytoplasm.
Basal lamnia encloses it and
capillary plexus is
present .

44. Numerous elongated
mitochondria in narrow
cytoplasmic partitions
separated by highly folded and
interdigitated basolaterla cell
membrane.
Apical cytoplasm contain secretry
granules which contain
kallikrein
It also contains numerous
lysosomes and peroxisomes
and deposits of glycogen.
Adjacent cells are joined by well
developed tight junction but
lack gap juction

45. they locate in the
connective tissue
septa btwn the lobules
of the gland.
They are larger in
diameter than striated
duct and typically
have pseudostratified
epithelium with
columnar cells

46. as the duct increase in
size the number of
mitochondria and
the extent of
infolding of
basolateral
membrane decrease

47. Purely serous
Intercalated cells are
numerous and long in
it
Striated duct are
numerous and appear
acidophillic .

48. Mixed, 90% serous 10%
mucous
The intercalated and
striated ducts are less
numerous than those
in parotid
Secretes lysozymes
1: intralobular ducts/ striated
ducts
2: mucous acinus
3: serous demilunes

49. Mixed gland, but mucous
secretory cells
predominate.
The intercalated duct are
short and difficult to
recognize.
Intralobular ducts are
fewer in number and
some duct lack the
infolded basolateral
membrane of striated
duct

50. - the secretory end
pieces of most minor
glands are mucous or
have a small serous
component .
- intercalated duct often
poorly developed and
the larger duct may lack
infolded basolateral
membrane of striated
duct.
- Von Ebner gland is
purely serous , located
below the circumvallate
papillae

51. AGING :
- Generalized loss of SG parenchymal tissue, a
gradual reduction of up to 30% to 60% in the
proportional acinar volume.
- The lost salivary cell is replaced by adipose cell.
- An increase In fibrous connective tissue and
vascular elements.
- Changes of the duct system including an increase in
nonstriated intralobular ducts, dilation of
extralobular duct and degenerative and metplastic
occure.

52. - Although decreased production of saliva often is
observed in older persons wether this is related
directly to the reduction in parenchymal tissue is
not clear yet.
- Some studies of healthy older individuals in which
the use of medication were controlled carefully
revealed little or no loss of salivary function.
- Other studies suggest that although resting salivary
secretion is in the normal range the volume of
saliva produced during stimulated secretion is less
than normal

53. Sialoliths are common in the submandibular
gland duct, because……..
Anatomical course of wharton’s duct has sharp
curves which may trap mucin/calculus
High mucin level of the gland may trap foreign
bodies &debris
Calcium content is higher in the saliva of
sub.mand. Gland
Flow rate of the saliva is slower than parotid
Dependent position of the gland increases chances
of stasis of saliva

54. Clinical features:
Intermittent swelling
in the region of major
salivary gland that
enlarges during eating
and resolves later
Pain because of the back
up saliva behind the
stone

55. Stasis of saliva may lead
to infection /fibrosis
/atropy of the gland
Sinus /fistula and
ulceration in chronic
cases
They may be palpable if
they are at periphery of
the duct
They are circumscribed
&firm to hard masses

56. Etiology /p. factors
[Debatable]
Inflammation
Drugs [anticholenergic
medications,antihista
mines]
Defects in calcium and
phospharous
metabolism
- Ttt could be by surgery
or antibiotic

57. - Clinical compliant.
- Loss of salivary function or a reduction in the
volume of secreted saliva may feel to the sensation
of oral dryness.
- Most commonly as a side effect of medications taken
by the patient which cause central or peripheral
inhibition of salivary secretion.
- Destruction of salivary gland tissue another cause.
-Loss of gland function occurs after radiation
therapy for head and neck cancer.
- Chemotherapy for cancer or associated with bone
marrow transplantation also reduce salivary
function

58. - Autoimmune disease in
particular sjogren
syndrom.
-The decreased volume
of saliva leads to
drying of oral tissue.
Loss of the protective
effect of salivary
buffers prtn and
mucin-

59. - The oral tissues are
more susceptible to
infections
- Speech, swallowing
and eating become
very difficult and
painfull
- Teeth are highly
susceptible to caries
especially near the
gingival margin

60. - Temporary relief is achieved by frequent sipping
of water or artificial saliva.
- Patient who have some functional salivary tissue
may benefit from pharmacologic therapy with
oral parasympathomimetic drugs such as
pilocarpine to increase salivary flow.
- Satisfactory ttt may include genetic modification
of salivary gland cells to increase fluid and
protein secretion