chapter of salivary gland for dental students

1. Saliva & Salivary glands
lecture 1
Dr: Mahmoud 3mmar
Mobile: 0106 39 700 30
f.b: m.3mmar9428@yahoo.com

2. Contents of chapter:
1. Definition of saliva, its contents.
2. Functions of saliva.
3. Classification of salivary glands.
4. Histological structure.

4. 1)Definition of saliva:
its complex fluid (99%water , Ca , Po4 , F & protein , glycoprotein and
enzymes) , produced by salivary glands , has important
role in maintaining the well condition of the mouth.
2)Functions of saliva:
1- protection
2- buffering action.
3- maintenance tooth integrity.
4- digestion.
5- defense (antimicrobial action).
6- taste.
7- tissue repair.

5. active
component.
effect of this
function
Functions of
saliva
1) Glycoprotein
& mucins.
2) water.
3) Protein , Ca.
1) Lubrication & act as barrier to microbial products.
2) washing action: by removal of bacteria , its
toxins and debris from the
mouth & decrease the action
of acido-genenic bacteria by
clearance the sugar.
3) Salivary pellicle: its thin coat on the tooth
surface formed by binding between Ca ,
protein .
1-protection
Po4 ,
bicarbonate
Maintain the natural PH of the oral
cavity.
.2-buffering
action
Calcium Ca,
phosphate PO4
& flouride F
1) post-eruptive maturation of enamel.
2) Repair , remineralization .
3) Protection by washing action.
3- Tooth
integrity

6. 1- lyso-somes.
2-lactoferin.
3- IGA
4- mucins
5- water
1- hydrolysis of the cell wall of some bacteria.
2- Binding of some elements which is essential
for bacteria.
3- immune defense mechanism.
4- act as physical microbial barrier
5- mechanical effect by washing action.
.5- defense
-(bacterio
static)
1) protein gustin.
.2) water
.1) maturation of taste buds
.2) washing taste bud from debris
6- taste.
Growth factors1) Epithelial regeneration 2) Wound
healing
7- tissue
repair.
1) water.
2) amylase
3) maltose , lipase
.4) po4 , bicarbonate
1) bolus formation .
2) digest the starch into glucose.
3) digest triglyceride into mono , di- glycride
4) netralize esophageal contents
4- digestion.

7. Salivary glands: are compound , tubulo-acinar ,
merocrine , exocrine glands whose
ducts open in oral cavity that
produce , secrte saliva.
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3) Classifications of salivary glands according to
their:-
1- location. (oral vestibule & oral cavity proper)
2- size. (major & minor )
3- nature of secretion. (pure serous & pure mucous & mixed)
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8. 1- According to their location.
1) glands of oral vestibule
a- labilal G b- buccal G. c- parotid G.
2) glands of oral cavity proper:
1- G of the floor of the mouth.
a. sub-mandibular glands.
b. major , minor sub-lingual glands
c. glosso-palatine glands.
2- G of tongue.
a. anterior lingual glands (blandin nuhn)
b. posterior lingual glands (vonebner , weber glands)
3- G of the palate
a. postero-lateral of hard palate glands.
b. soft palate glands.
c. uvula glands.

9. 2- according to size
1) major < 3 pairs >
a. parotid glands: oppen at buccal vstibule opposite to upper molars
b. sub-lingual glands: open on each side of lingual frenum.
c. sub-mandibular glands: open at posterior part of floor of mouth
2) minor: its separated small mucosal glands in different areas in the mouth.
N.B: major salivary glands
don’t act during sleep
while minor glands act 24 h .

10. 3- according to nature of secretion
1) pure seous glands
a. von-ebner salivary glands (post. lingual)
b. Adult human parotid glands
2) pure mucous glands
a. weber glands (post. lingual)
b. anterior portion of ant. Lingual gland (blandin nuhn).
c. minor sub-lingual glands.
d. glosso-palatine glands.
e. palatine glands.
N.B: no major gland secrete pure mucous

11. 3) Mixed glands:
A) mixed predominantly serous.
1- parotid of new born.
2- sub-mandibular glands 80%
B) mixed predominently mucous.
1- major sub-lingual glands.
2- post. Portion of ante. Lingual glamds(blandin nuhn).
3- buccal glands.
4- labial glands.

12. Vestibular & Major & pure serous in adult , mixed
predominantly mucous in new born
Parotid glands
Oral cavity proper & major & mixed predominantly
serous
Sub-mandibula glands
Oral cavity proper & major & mixed predominantly
mucous
Major Sub-lingual glands
Oral cavity proper & minor & pure-mucousMinor sub-lingual glands
oral cavity proper & minor & pure mucousAnterior portion of blandin
nuhn glands
Oral cavity proper & minor & mixed predominantly
mucous
Posterior portion of
blandin nuhn glands
.Oral cavity proper & minor & pure serousVonebner glands
Oral cavity proper & minor & pure mucous.Weber glands
Oral cavity proper & minor & pure mucousPalatine glands
Vestibular & minor & pure mucousGlosso-palatine glands

13. Parotid Gland
Duct: Stenson’s duct
Submandibular
Gland
Duct:Wharton’s
duct
Sublingual
gland
Ducts
•Bartholin’s duct
•Revinous ducts (8-20 in number)
Major Salivary Glands

14. 4) Histological structure of salivary glands:-
1) frame work of C.T elements < stroma >:
(cells , fibers , G.S , B.V , nerves)
2) parenchymal elements:
1- secretory cells (acini) : a. serous b.mucous.
2- Non-secretory cells : a. myo-epith b. oncocyte.
3- duct system
a. secretory duct (intercallated . striated)
b. Excretory duct.
c. main duct.

16. 1) Frame work of connective tissue elements:-
 Its capsule which surround , protect the gland .
 Its septa extend to subdivide the glands into major lobes &
lobes further subdivided into lobules.
 C.T contains cells , fibers , G.S
 C.T support the B.V , lymphatic
& nerves that supply the gland

17. 2) Parenchymal elements they are composed of:-
1- secretory cells. (serous , mucous cells)
2- Non-secretory cells (myoepith. Cells , oncocyte)
3- duct system (secretory , excretory . Main ducts)

21. (secretory cells & Non-secretoty cells & duct system)
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1) secretory cells (acini): cluster of cells varies in
shape , size that resemble a many-lobe berry ,
its either (serous or mucous or mixed)

22. Comparison :serous , mucous acini (histological structure)
mucous aciniserous acini
tubular long
acini
sphereShape of acini
largesmallSize of acini
largernarrowlumen
short cuboidal or
.flattened
pyramidal , its apical
.toward lumen
Shape of cells
1 layer or more1 layerNumber of cells
Flattened or angularsphereShape of nucleus
compressed against
basal cell membrane
Basal thirdSite of nucleus

25. Comparison srous , mucous (ultra structure):-
Serous cell
with intercellular canaliculi
Mucus
cell

26. Mucous cellsSerous cells
mucinProtein thus cell show all features of
synthesis , storage , secretion of protein.
Cell synthesis
*By H,E its pale , vaculated.
*Cells appear empty except
numerous mucigen granules &
thin film of cytoplasm forms
trabecular network.
By H,E its deeply stained basophilic.
1- apical cytoplasm: contain zymogen
secretory granules.
2- basal cytoplasm: basal striation due to
numerous arranged parallel RER.
cytoplasm
Compressed basallyrounded basallynucleus
Few RER.
10:12 prominent Golgi complex
Few mico-villi
mitochondria
*Large amount of RER &4:6 prominent.golgi
Golgi omplex (basal . Lateral to nucleus)
.*Mitochondria , lysosomes
*Microfilaments, microtubules.
organelles
Very few inter-cellular
canaliculi
Junctional complex , desmosomes.Intercellular
canaliculi ends
in form of:
Granules expelled with their
membrane intact then it will
lostoutside
Granule unit with membrane of cells . Then
ruptures , its contnts secreted to outside cells
Exocytosis
secretion

28. 2) Non-secretory cells:(myoepithelial. Cells & oncocyte)
1) myoepith. Cells (basket cells) :
*its spindle shape cells has 4:8 process .
*related to secretory cells , inter-callated duct .
*attached to underlying cells by desmosomes .
* contains many microfilaments which collect to form darkb odies.
* cells organelles are peri-tubular.
Myo-
ePithelial
cells.

29. Function : its has contractile
function which is:-
decrease luminal volume
thus
increase the secretory
pressure
thus
accelerate the initial flow
of saliva.

30. 2) oncocyte: its spherical large cells found mostly in ducts ,
represent an age changes .
histologically: a. cells: spherical , large.
b. nucleus: peknotic (shrinkage nucleus) ,
centrally placed in the cell.
c. cytoplasm: strong esinophilic.
loaded by mitochondria
site: in ducts.
age: old age

31. Thanks
Dr: 3mmar