saliva is known as body's mirror. it is used as a diagnostic biomarker for various pathological conditions.

1. SALIVA
PRESENTED BY:
ANUSHRI GUPTA
DEPT OF PERIODONTOLOGY

2. CONTENTS • INTRODUCTION
• SALIVARY GLANDS
Development
Structure of terminal secretory units.
Classification Of Salivary Glands
Major Salivary glands
Minor Salivary glands
Nerve supply to salivary glands
• FORMATION OF SALIVA
• PROPERTIES OF SALIVA
• COMPOSTION OF SALIVA
• FUNCTIONS OF SALIVA
• REGULATION OF SALIVA
• CO-REALATION BETWEEN SALIVA AND DENTAL CARIES
• SALIVA AS DIAGNOSITIC AID
• COLLECTION OF SALIVA
• SALIVA AND DENTAL PLAQUE
• CLINICAL CONSIDERATION OF SALIVA
• EFFECT OF DRUGS & CHEMICAL ON SALIVARY SECRETION
• CONCLUSION
• REFERENCES

3. INTRODUCTION
• The oral cavity is a moist environment;
a film of fluid called saliva constantly coats
its inner surfaces and occupies the space
between the lining oral mucosa and teeth.
• Saliva is a complex fluid, produced by the salivary glands, whose
important role is maintaining the well being of mouth.
• Human saliva consist of organic and inorganic components and
plays an essential role in mastication, in bolus formation, acts as
a lubricant in swallowing, helps in speech production and
protecting the mucosal surfaces of the oral cavity from
desiccation.

4. • The enzymes found in saliva are essential in beginning
the process of digestion of dietary starches and fat.
• Saliva circulating in mouth at any given time is termed
“whole saliva”.
• Saliva reflects the physiological state of body including
emotional, endocrinal, nutrional and metabolic
variations also known as “THE BODY’S MIRROR”

5. DEFINITION
According to Stedman’s dictionary
“Saliva is clear, tasteless, odourless slightly acidic (ph 6.8) viscid fluid, consisting of
secretions from the parotid, sublingual and submandibular salivary glands and the
mucous glands of the oral cavity.”
According to Webster Medical Dictionary
The watery tasteless liquid mixture of salivary & oral mucous glands secretion that
lubricates the chewing food , wets the oral wall & contains the enzyme ptyalin
which function in the pre-digestion of starch.

6. DEVELOPMENT
• The Primordia of the glands of humans
appear during sixth week of foetal life.
• Primordium of sublingual glands appear
after 7 to 8 weeks.
• The minor salivary glands begin their
development during the third month.
ORAL EPITHELIAL
BUDS
ECTODERMAL ENDODERMAL
PAROTID GLAND
AND MINOR
SALIVARY GLANDS
SUBLINGUAL AND
SUBMANDIBULAR
GLANDS
MESENCHYME
ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

7. STAGES OF DEVELOPMENT
• The epithelial bud grows into an extensively
branched system of cords of cell that are first
solid but gradually develop a lumen and become
ducts.
• The secretory portions develop later than the
duct system and formed by repeated branching
and budding of the finer cell cords and ducts.
• Since salivary glands are formed from an initially
solid core of epithelial cells –for the proper
functioning of the gland, the duct needs to
undergo cavitations -to allow free access
between the saliva producing acini and oral
cavity- known as Canilicular Stage.
PRE BUD
INITIAL BUD
PSEUDO GLANDULAR
CANALICULAR
TERMINAL BUD
ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

8. STRUCTURE OF TERMINAL SECRETORY
UNITS
• Salivary glands are made up of cells which are arranged in
small groups around a central globular cavity called acinus
& alveolus.
• The central cavity is continuous with the lumen of the
duct.
• The fine duct draining each acinus is called the
intercalated ducts.
• Many intercalated ducts join together to form intralobular
ducts.
• Two or more intralobular ducts join to form excretory
ducts , which unite to form the main duct of the gland.
• The gland with this type of structure & duct system is
called racemose type.
• Racemose means the bunch of grapes.
ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

9. CLASSIFICATION OF SALIVARY GLANDS
(a) According to size and location
MAJOR SALIVARY
GLANDS
PAROTID GLAND
SUBMANDIBULAR
GLAND
SUBLINGUAL
GALND
MINOR SALIVARY
GLANDS
LINGUAL SEROUS
LINGUAL MUCOUS
BUCCAL GLANDS
LABIAL GALNDS
PALATAL GLANDS

10. MAJOR SALIVARY GLANDS
PAROTID GLAND
• Parotid gland is the largest salivary gland.
• It is irregular, wedged shape and
unilobular.
• Parotid is 14-28 grams in weight and
provides 60-65% of total salivary volume.
• Size averaging 5.8 cm ( cranio-caudal
dimension), 3.4 cm (ventral-dorsal
dimension).
Human antomy by B.D chaurasia 4th edition

11. • These glands are situated at the side of the face just below and
in front of the ear .
• The main parotid duct – Stensens duct leaves mesial angle of
gland traverses over the massetter, pierces buccinator and
enters oral cavity buccal to maxillary 2nd molar.
• Duct is about 35 to 40 mm long .
• Mainly Serous in secretion.

12. SUBMANDIBULAR GLAND
• Also called as Submaxillary gland.
• Its irregular and Walnut shaped.
• It is 10-15gm in weight produce 20-
30% of total salivary volume.
• Located in the submandibular
triangle of the neck, inferior &
lateral to mylohyoid muscle.
Human antomy by B.D chaurasia 4th edition

13. • The posterior-superior portion of the gland curves up around the
posterior border of the mylohyoid and gives rise to Wharton’s duct .
• Wharton’s duct passes forward along the superior surface of the
mylohyoid adjacent to the lingual nerve.
• It is 2-4mm in diameter & about 5cm in length.
• Wharton’s duct, opens at the side of frenulum of tongue by the means
of small opening on the papilla called Caruncula Sublingualis

14. SUBLINGUAL GLAND
• The sublingual glands are the
smallest of the major salivary glands,
produces 2-5% of the total salivary
volume.
• Each is of the size and shape of an
almond .
• Weighs 3-4 gms.
• Glands lie beneath mucosa of floor of
mouth, above mylohyoid muscle,
medial to mandible and lateral to
genioglossus.
Human antomy by B.D chaurasia 4th edition

15. • The ducts of the sublingual glands are called Bartholin’s ducts.
• In most cases, Bartholin’s ducts consists of 8-20 smaller ducts of
Rivinus.
• These ducts are short and small in diameter.
• Open into oral cavity at the sublingual fold on either side of the
tongue.

16. MINOR SALIVARY GLANDS
• The minor salivary glands are located beneath the
epithelium in almost all parts of the oral cavity.
• These glands usually consist of several small groups
of secretory units opening via short ducts directly
into mouth.
• There are 600 to 1000 minor salivary glands lying in
the oral cavity and the oropharynx.
• The minor salivary glands are classified according to
their anatomic location.
MEDICAL PHYSIOLOGY BY SEMBULINGAM 4TH EDITION

17. 1. Labial and Buccal Glands
• Labial glands - situated beneath the mucous
membrane around the orifices
of mouth.
• They are circular in form, and about the size of
small peas; their ducts open by minute orifices
upon the mucous membrane.
• Buccal glands– present between the mucous
membrane and buccinator muscle.
2. Palatine Glands
• They consist of several hundred glandular
aggregates in the lamina propria of the posterior
region of the hard palate and in the submucosa
of the soft palate.
• The opening of the ducts on the palatal mucosa
are often large and easily recognized.

18. 3. Glossopalatine Glands
• The glossopalatine glands are pure mucous glands, they are
principally localized to the region of the isthmus in the glossopalatine
fold.
4. Lingual Glands
• The glands of the tongue are divided into several groups:
(a) The anterior lingual glands ( glands of BLANDIN AND NUHN )
• Location – near the apex of tongue.
• The anterior region of this glands are chiefly mucous in character,
whereas the posterior region is mixed.

19. (b) The posterior lingual mucous gland.
Location -- lateral and posterior to the vallate papillae and in association
with the lingual tonsil.
(c) The posterior lingual serous gland ( von Ebner’s glands)
Location -- between the muscle fibers of the tongue below the foliate and circumvallate papillae.

20. (b) According to the histochemical nature of secretory products.
• This type of gland is made up of serous cells
predominantly.
•These glands secrete thin & watery saliva .
•Parotid glands and lingual glands are serous glands.
SEROUS
GLANDS
•This type of glands are made up of mucous cells mainly
•These glands secrete thick & viscous saliva with more
mucin .
• Lingual mucous, buccal glands & palatal glands belongs
to this type.
MUCOUS
GLANDS
• Mixed glands are made up of both serous and mucous cells .
• Submandibular , sublingual & lacrimal glands are mixed
glands
MIXED
GLANDS
SEROUS CELL
MUCOUS CELL
Tencate’s oral histology- 6th Edition

21. Nerve supply to salivary glands
• Salivary glands are under the control of autonomic nervous system and receive
efferent nerve fibres from both parasympathetic and sympathetic divisions of
autonomic nervous system.
Parasympathetic fibers:
• The parasympathetic nerve fibers supplying the salivary glands arise from the
superior and the inferior salivatory nuclei, which are situated in pons and
medulla respectively.
Tencate’s oral histology- 6th Edition

22. Parasympathetic fibres to submandibular and sublingual glands.
• The parasympathetic preganglionic fibers to submandibular &
sublingual glands arise from the superior salivatory nucleus situated
in pons .
• After taking origin from this nucleus, the preganglionic fibers pass
through nervous intermedius of wrisberg, geniculate ganglion, the
motor fibers of facial nerve, chorda tympani branch of facial nerve &
lingual branch trigeminal nerve & finally reach the submaxillary
ganglion.

23. Parasympathetic fibres to parotid gland.
• The parasympathetic preganglionic fibres to
parotid gland arises from inferior salivatory
nucleus situated in the upper part of medulla
oblongata.
• From here, the fibres pass through the
tympanic branch of glossopharyngeal nerve,
tympanic plexus & lesser petrosal nerve and
end in otic ganglion.
• The postganglionic from otic ganglion reach
the parotid gland by passing through the
auriculotemporal branch in mandibular
division of trigeminal nerve
Tencate’s oral histology- 6th Edition

24. Sympathetic fibers
• The sympathetic preganglionic fibres to
salivary glands arise from the lateral
horns of first and second thoracic
segments of spinal cord.
• The fibres leave the cord through the
anterior nerve roots and end in superior
cervical ganglion of the sympathetic
chain.
• The postganglionic fibres from this
ganglion are distributed to the salivary
glands along the nerve plexus around
the arteries supplying the glands
Tencate’s oral histology- 6th Edition

25. FORMATION OF SALIVA
• The secretory acinus produces the primary saliva, which is isotonic with an
ionic composition resembling that of plasma.
• In the duct system, the primary saliva is then modified by selective
reabsorption of Na+ and Cl- (without water) and secretion of K+ and HCO3-.
• Salivary secretion is a two-stage process:
Initial Formation stage involves acini to secrete a primary secretion that
contains ptyalin and/or mucus in a solution of ions similar in plasma.
Modification stage is when the primary secretion flows through the ducts
and the ionic composition of saliva is modified.
The salivary gland fluid secretion mechanism The
Journal of Medical Investigation Vol. 5638 2009

26. Initial Formation Stage:
• Stimulation of the parasympathetic nerve, or mainly muscarinic
cholinergic receptors, initiates intracellular second messenger events
of acinar cells, the signal transduction system involves the release of
Ca2+ from intracellular stores.
• The increase in intracellular Ca2+ levels leads to the Cl– channels at
the apical membrane to open and an influx of Cl– into the lumen.
• Hence the change in electronegativity by Cl– influx causes Na+ to
diffuse across the cation-permeable tight junction between acinar
cells to preserve electroneutrality within the lumen.
• The net influx of NaCl creates an osmotic gradient across the acinus,
which draws water from the blood supply via a tight junction.
• Thus, saliva secreted in the lumen (primary saliva) is an isotonic
plasma-like fluid.

27. Modification Stage:
• In the next step, the composition of primary saliva is modified in the duct system.
• The intralobular ducts reabsorb Na+ and Cl– excluding water, and make the final
saliva hypotonic.
• Stimulation of the sympathetic nerve, or ß-adrenergic receptors, causes exocytosis
but less fluid secretion.
• Activation of ß-adrenoceptors increases the intracellular cyclic adenosine
monophosphate (cAMP) level, which is the primary second messenger for amylase
secretion.
• cAMP is thought to activate protein kinase which may regulate the process by
which cells release the contents of their secretory granules.
• This involves the fusion of the granule membrane with the luminal plasma
membrane of the secretory cell followed by rupture of the fused membranes.
• The released contents of granules
comprise a wide variety of proteins
which are unique to saliva and show
biological functions of particular
importance to oral health.

28. REGULATION OF SALIVARY SECRETION
• Salivary secretion is regulated by nervous mechanism & it is a reflex
phenomenon.
• Salivary reflexes are of two types:-
1)Unconditioned reflex
2)Conditioned reflex
1) UNCONDITIONED REFLEX
• Secretion of saliva when any substance is played in the mouth is called the
unconditioned reflex.
• It is due to the stimulation of nerve endings in the mucuos membrane of the
oral cavity.
• This reflexes is present since birth & hence it is also called inborn reflex.

29. 2) CONDITIONED REFLEX
• Secretion of saliva by the sight,smell,heaving or thought of
food is called conditioned reflex.
• It is due to the impulses arising from the eyes,ear,etc.
• It is an acquired reflex & needs previous experience

30. PROPERTIES OF
SALIVA
i) VOLUME:- 1000 to 1500 ml of saliva is secreted per day and, it is
approximately about 1ml/minute . Contribution by each major salivary
gland is
ii) REACTION:- mixed saliva from all the glands is slightly
acidic with pH of 6.35 to 6.85.
– pH becomes alkaline with high flow rates.
– Bacterial action may also alter the pH of saliva.
iii) SPECIFIC GRAVITY:- it ranges between 1.002 to 1.012.
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 More alkaline
HUMAN PHYSIOLOGY BY A.K. JAIN 5th edition

31. iv)TONICITY :- saliva is hypotonic to plasma.
v) Freezing point – 0.07-0.34°C
vi) Osmotic pressure – ½ -3/4 of blood (1400 milliosmol/L)
vii) Flow rate – 0.02ml / min. – At rest
7ml / min. – In stimulated saliva.
viii) Velocity – 0.8-8mm/min.
– Lowest velocity films occurred on facial surfaces of upper incisors
– Highest velocity occurred on lingual surfaces of teeth.

32. ix) VISCOSITY-‘SPINN BARKEIT PHENOMENA’
• Viscosity depends on their glycoprotein content as
described by Gottschalk 1961.
• viscoelastic properties.
• Ability to draw out a thread of saliva is typical of a
viscoelastic fluid and is known “Spinn Barkeit”.
• The relative viscosity of the three main secretions after
acetic acid stimulation were found by Schneyer (1955).
1. Parotid - 1.5
2. Submandibular - 3.4
3. Sublingual - 3.4
ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

33. Critical pH
• “The pH at which any particular saliva ceases
to be saturated with calcium and phosphate is
referred to as ‘ critical pH ’
• It is usually 5.5
• High salivary calcium and phosphate- Remineralization
• Low calcium , phosphate – Demineralization
Tencate’s oral histology- 6th Edition

34. COMPOSITION SALIVA
WATER-99.5%
Organic substance
Enzymes
1. Amylase
2. Maltase
3. Lingual lipase
4. Lysozyme
5. Phosphates
6. Carbonic
anhydrase
7. kalikrein
Other org. substances
1.Proteins- mucin
& albumin
2. Blood group
antigen
3. Free amino
acids
4. Non protein
nitrogenous
sustances-urea,
uric acid,
creatinine,
xanthine,
hypoxanthine
SOLIDS-0.5%
Inorganic substance
1.Sodium
2.Calcium
3.Potassium
4.Biocarbonate
5.Bromide
6.Chlorine
7.Fluoride
8.phosphate
1.Oxygen
2.Carbon
dioxide
3.Nitrogen
ORAL HISTOLOGY AND EMBRYOLOGY –
ORBAN’S. 13TH EDITION

35. A. Organic Substances
Enzymes
1- Amylases
• abundant salivary enzyme (50 % of proteins )
• 80 % - parotid
• Hydrolyzes starches →maltose (20% of glucose), dextrins
Appears to have digestive, antibacterial and tissue coating functions.

36. 2- Lactoferin
• Iron binding glycoprotein secreted by serous cells
• High affinity for iron
• “Nutritional“ immunity (iron starvation).
• Bacteriostsatic, cidal, antifungal, antiviral and anti inflammatory
3- Lingual lipase
• Secreted by von Ebner’s glands of tongue.
• Involved in first phase of fat digestion.
• It provides medium for hydrolyzing fats or long chain triglycerides into fatty acids.
• Increase the efficacy of pancreatic polypeptide
• It is highly hydrophobic and readily enters fat globules.
• Important in digestion of milk fat in new-born.

37. 4- STATHERINS
• Calcium phosphate salts of dental enamel are soluble under typical
condition of ph and ionic strength.
• It does super saturation of calcium phosphates maintain enamel integrity.
• Secreted by acinar cells
• Both Parotid and submandibular glands
• prevent precipitation or crystallization of supersaturated calcium
phosphate in ductal saliva and oral fluid
• Also an effective lubricant.

38. 5- Proline Rich Proteins (PRPs)
• Like statherins, PRPs are also highly asymmetrical.
• Inhibitors of calcium phosphate crystal growth
• Present in the initially formed enamel pellicle & in ‘mature’ pellicle.
6- Lysozyme ( LZ )
• Oral LZ is derived from
1. major and minor salivary glands
2. phagocytic cells
3. gingival crevicular fluid (GCF)
• Is an antibacterial enzyme.
• The mean concentration in whole saliva -resting is 2.2mg/100ml
- stimulated-11mg/100ml.

39. • Performs anti-microbial activity by:
• Inhibition of bacterial adhesion to tooth surfaces
• Inhibition of glucose uptake and acid production
• Muramidase activity (lysis of peptidoglycan layer)
7- Histatins
• A group of small histidine-rich proteins
• Potent inhibitors of Candida albicans growth.
• Perform wound healing

40. 8- Kallikrein
• It splits beta-globulin into bradykinin
• Bradykinin passes back into the gland and into blood vessels, thus causing
functional vasodilatation, to supply an actively secreting gland.
9- Cystatins
• Are inhibitors of cysteine-proteases
• Are ubiquitous in many body fluids
• Considered to be protective against unwanted proteolysis
 bacterial proteolysis
 Lysis of leukocytes
• May inhibit proteases in periodontal tissues.

41. 10- Agglutinins
• Interact with unattached bacteria
• Cause clumping of bacteria into large aggregates
which are easily flushed by saliva
11. Glycoprotein Mucin
• Protective coating about hard and soft tissues
• Formation of acquired pellicle
• Concentrates anti-microbial molecules
• Lubrication
• Forms a moist mucosal environment

42. IMMUNOGLOBULINS
• Secretory Ig A - inhibit adhesion – 90%
• Ig G – enhance phagocytosis
• Ig M - enhance phagocytosis
• Ig A has 3 main functions:
– Inhibition of bacterial colonization.
– Binding to specific bacterial antigen.
– Affects specific enzymes essential for bacterial metabolism
Blood group substances:
• Blood group antigens are also present in saliva, Ag A and AgB.

43. HORMONES
• “Parotin” and a “nerve growth factor”.
• Parotin – facilitates calcification and helps to maintain serum calcium levels.
• Nerve Growth Factor (NGF) – affects growth and development of symphathetic
nerve fibres.
CARBOHYDRATES
• Has glucose at a concentration of 0.5-1mg/100ml (parotid).
• In submandibular – glucose, hexose, fructose with small amounts of
hexosamine and sialic acid.

44. Amino acids
• 9 types in parotid
• 12 in submandibular
• 18 in whole saliva at low concentration of about 0.1mg /100ml.
Lipids
• Small amount of diglycerides, triglycerides, cholesterol and cholesterol esters,
phospholipids, corticosteroids.
• Play a role in salivary protein binding ,bacterial absorption to apatite, and plaque
microbial aggregation.

45. B. Inorganic Substances
1- SODIUM
• Contributes to osmolarity of saliva(osmolarity is ½-3/4th of blood).
• Sodium concentration give diagnostic information relating to the efficiency
of ductal transport system.
2- CALCIUM
• saliva is supersaturated with calcium and hence prevents dissolution of
enamel.
• it also facilitates enamel mineralization.

46. 3- POTASSIUM
• Contributes to osmolarity of saliva.
• Potassium reaches saliva by active processes in both acini and ducts.
• Concentration falls immediately after stimulation and then approximately
constant.
4- BIOCARBONATE
• Most important buffer in saliva [resist change in salivary Ph when acid or alkali
added].
• Biocarbonates release weak carbonic acid when acid is added; this is rapidly
decomposed to H2O and CO2 which leaves the solution resulting in complete
removal of acids.

47. 5- CHLORINE
• Contributes to osmolarity of saliva.
• Increased flow rate leads to increased chloride reabsorption.
6- FLUORIDE
• fluoride is well known for its anti-caries property.
• peak concentration of fluoride in gland saliva are observed some 30-60
minutes after ingestion of fluoride dose.
7- PHOSPHORUS
• it is actively transported into saliva,probably mainly in the acini but possibly
also in the ducts

48. FUNCTIONS OF SALIVA
1) PREPARATION OF FOOD FOR SWALLOWING
• When food enters the mouth , saliva moistens
and dissolves it.
• The mucous membrane of mouth is also
moistened and masticated food is rolled into
a bolus.
• The mucin of saliva lubricates the bolus and
facilitates the swallowing.
2) APPRECIATION OF TASTE
• Taste is a chemical sensation.
• Saliva by its solvent action dissolves the solid
food substance , so that the dissolved
substances can stimulate the taste buds.
• The stimulated taste buds recognize the taste.
ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

49. 3) DIGESTIVE FUNCTION
Saliva has three digestive enzymes namely,salivary amylase,maltase,and
lingual lipase
SALIVARY AMYLASE
• salivary amylase is a carbohydrate splitting (amylolytic) enzyme.
• It acts on cooked or boiled starch and converts it into maltose ,major part of it
occurs in the stomach because, the food stays only for a short time in the
mouth.
• The optimum pH necessary for the activation salivary amylase is 6.
• The salivary amylase cannot act on cellulose.
MALTASE
• The enzyme maltase is present only in traces in human saliva.
• It converts maltose into glucose.
LINGUAL LIPASE

50. 4) CLEANSING AND PROTECTIVE FUNCTION
• due to the constant secretion of saliva, the mouth and teeth are rinsed and kept
free from food debris, shed epithelial cells and foreign particles.
• In this way, saliva prevents bacterial growth by removing materials, which may
serve as culture media for the bacterial growth.
• the enzyme lysozyme of saliva kills some bacteria such as staphylococcus,
streptococcus and brucella.
• mucin present in the saliva protects the mouth by lubricating the mucous
membrane of the mouth.

51. 5) ROLE IN SPEECH
• By moistening and lubricating the soft parts of mouth and lips, saliva helps
in speech.
• If the mouth is dry, articulation and pronunciation become difficult.
6) EXCRETORY FUNCTION
• Many substances, both organic and inorganic, are excreted in saliva.
• It excretes substances like mercury, potassium iodide, lead and
thiocyanate.
• Saliva also excretes some viruses such as those causing rabies and mumps
• In some pathological conditions, saliva exretes substances like sugar in
diabetes mellitus, calcium in hyperparathyroidism.

52. 7) REGULATION OF BODY TEMPERATURE
• In dogs and cattle excessive dripping of saliva during panting helps in loss of
heat and regulation of body temperature.
• However, in human being sweat glands play major role in the temperature
regulation and saliva does not play any role in this function.
8) REGULATION OF WATER BALANCE
• When the body water content decreases ,salivary secretion also decreases.
• This causes dryness of the mouth and induces thirst.
• When the water is taken, it quenches the thirst and restores the body water
content.

53. SALIVA AND DENTAL PLAQUE
• Whole saliva has long been known to contain large
numbers of bacteria.
• Saliva exerts shearing forces as it flows.
• This might lead to passive detachment of some microbes
from biofilm surfaces.
• However, the unstimulated velocity of the salivary film is
low in most regions of the mouth.
• Biofilm bacteria play an active role in their transition to
the planktonic state.
• In several biofilm models, sessile bacteria produce
enzymes that promote their release into the fluid
medium.
• Similar mechanisms have been observed for biofilms of S.
mutans, the primary etiologic agent of dental caries .
Carranza’s clinical periodontology- 10 th edition

54. CO-REALATION BETWEEN SALIVA AND
DENTAL CARIES
• Saliva is capable of regulating the pH of the oral cavity
by the help of its bicarbonate content as well as its
phosphate and amphoteric protein constituents.
• Increase in secretion rate usually results in an increase
in pH and buffering capacity.
• Because of its calcium and phosphate content, it helps
to maintain the integrity of teeth.
• Tooth dissolution is prevented or retarded and re-
mineralization is enhanced by the presence of copious
salivary flow.
• The flow of saliva can reduce plaque accumulation on
the tooth surface.
• The diffusion into plaque of salivary components such
as calcium, phosphate, hydroxyl and fluoride ions
enhances re-mineralization of early carious lesions. ORAL HISTOLOGY AND EMBRYOLOGY – ORBAN’S. 13TH EDITION

55. • The carbonic acid-bicarbonate buffering system as well as ammonia
and urea constituents of the saliva act as buffer
• The total concentration of IgA in saliva may be inversely related to
caries experience.
• Lysozyme, lactoperoxidase and lactoferrin in saliva have a direct
antibacterial action on plaque.
• Salivary proteins could increase the thickness of the acquired pellicle
and so help to retard the movement of calcium and phosphate ions
out of enamel.

56. Salivary Flow Rate, Buffer Effect and Dental Caries
• Probably the most important caries-preventive functions of
saliva are the flushing and neutralizing effects, commonly
referred to as "salivary clearance" or "oral clearance capacity“
(Lagerlof and Oliveby, 1994).
• In general, the higher the flow rate, the faster the clearance
(Miura et al., 1991) and the higher the buffer capacity
(Birkhed and Heintze, 1989).
• Reduced salivary flow rate and the concomitant reduction of
oral defense systems may cause severe caries and mucosal
inflammations (Daniels et al., 1975; Van der Reijden et ah
1996).
• Dental caries is probably the most common consequence of
hyposalivation (Brown et al, 1978; Scully, 1986).

57. SALIVA - AS A DIAGNOSTIC AID
• Human saliva performs a wide variety of biological functions that are critical for the maintenance
of the oral health.
• Saliva, a multi constituent oral fluid, has high potential for the surveillance of general health and
diseases.
Why saliva?
• Non – invasive, Easy, No pain, No needle prick, Fast
• Limited training
• No special equipment
• Potentially valuable for children and older patients
• Cost effective
• Eliminates the risk of infection
• Screening of large population
Diagnostic Uses of saliva-Mandel I D. Journal of Oral Pathology and Medicine March 1990:19(3);119-25

58. What is a biomarker?
• A biomarker is an objective measure that has been evaluated and
confirmed either as an indicator of physiologic health, a pathogenic
process, or a pharmacologic response to a therapeutic intervention.
• Biomarkers, whether produced by normal healthy individuals or by
individuals affected by specific systemic diseases, are tell - tale
molecules that could be used to monitor health status, disease onset,
treatment response and outcome.

60. • Salivary biomarkers have been used to examine the effect of lifestyle
factors, including smoking, on periodontal health.
• Levels of salivary markers including prostaglandin E2, lactoferrin,
albumin, aspartate aminotransferase, lactate dehydrogenase, alkaline
phosphatase were significantly lower in current smokers than in non-
current smokers.
Proteomic Biomarkers for Periodontal disease
• IL 1,2,4,10
• MMP 1, MMP 8
• PGE2
• TNFα
• fibronectin degrading enzymes
• IgA
• Epidermal growth factor (EGF)
• Vascular endothelial growth factor (VEGF)
Kaufman E, Lamster IB. Analysis of saliva for periodontal diagnosis. A review J Clini Periodontol 2000

61. • Microbial Biomarkers in saliva

62. Stress biomarkers in saliva.
• Salivary α-amylase & Chromogranin A
• Salivary cortisol
 Salivary – α amylase & Chromogranin A
• Both salivary CgA and a-amylase are considered biomarkers of the stress, response
by the sympatho– adreno–medullary system, unlike cortisol, which is considered a
biomarker of stress response by the Hypothalamic pituitary adrenal system.
 Salivary cortisol
• Its level in saliva is lower than that in blood.
• Advantage of salivary over serum cortisol measurement is the minimization of
stress from fear of needles during collection, which may bias the results.

63. Biomarkers for caries risk assessment
• The Levels of Salivary Mutans Streptococci and Lactobacilli
• Salivary Flow Rate
• Salivary pH and Buffer Capacity
• Salivary Proteins (mucin 7,PRPs)
• alpha-defensins HNP1-3 (Human neutrophil peptide) in children
• salivary IgA levels

64. MALIGNANCY
In some malignant diseases, markers can be detected in saliva, such as the presence of
protein p53 in patients with oral squamous cell carcinoma.
• Other biomarkers for OSCC:
• M2BP (Mac-2-binding protein)
• MRP14 (Myeloid related protein 14)
• CD59
• Profilin
• Catalase
• ICTP (Type 1 collagen degradation product)

65. SALIVA COLLECTION METHODS
Whole saliva collection method:

68. Saliva as a storage medium
• Storage product should not be stored for
more than one hour.
• Stored in buccal vestibular area or in a
container
• Its osmolality is much lower than the
physiologic saliva.
• It can damage PDL
• Chance of infection is high.
• More readily available
• Better than tap water or dry state.
Badruddin et al storage medium for avulsed teeth Indian Journal of Multidisciplinary Dentistry, Vol. 3, Issue 3, May-July 2013.

69. CLINICAL CONSIDERATIONS OF SALIVA
A. HYPOSALIVATION
The reduction in the secretion of saliva is called hyposalivation.
It is of two types , namely - Temporary
- Permanent
1) Temporary hyposalivation occurs in i) emotional conditions like fear
ii) fever
iii) dehydration
2) Permanent hyposalivation occurs in i) sialolithiasis – obstruction of salivary duct
ii) congenital absence or hypoplasia of
salivary glands
iii) bell’s palsy – paralysis of facial nerve
Oral medicine, Burket’s-11th edition.

70. 1. Dry mouth (Xerostomia)
• It is a frequent clinical complaint
• A loss of salivary function or a reduction in the
volume of secreted saliva may lead to the
sensation of oral dryness.
• This occurs as a side effect of mediations taken
by the patient for other problems.
• Many drug cause central or peripheral inhibition
of salivary secretion.
• Destruction is another common cause.
• Loss of gland function occurs after radiation
therapy for head and neck cancer because the
glands are included in the radiation field,
chemotherapy may also cause this condition.
• Temporary relief is achieved by frequent sipping
of water or artificial saliva .
Textbook of Oral Pathology- Shafer, Hine & Levy- 7th edition

71. 2. SJOGREN’S SYNDROME
• It is a chronic autoimmune disorder
characterized by xerostomia (dry mouth),
xerophthalmia (dry eyes), and lymphocytic
infiltration of the exocrine glands.
• This triad is also known as the sicca complex.
• It is an autoimmune disorder in which the
immune cells destroy exocrine glands such as
lacrimal glands & sweat glands .
• It is named after HENRI SJOGREN who
discovered it.
• In some cases it causes dryness of skin , nose.
• In severe condition the organs like kidneys,
lungs, liver , pancreas , thyroid , blood vessels
& brain are affected
Textbook of Oral Pathology- Shafer, Hine & Levy- 7th edition

72. 3. Age Changes
• With age a generalized loss of gland
parenchymal tissue occurs.
• The lost salivary cells often are replaced
by adipose tissue.
4. Caries
• A major problem of a reduced salivary
flow is the increased risk of caries as
saliva normally washes away acids.
• There may be an increase in recurrent
decay on coronal as well as root surfaces.
• Incisal edges of interior teeth may also
develop carious lesions as well as
recurrent lesions on the margins of
restorations.

73. 5. Dental erosion:
• Salivary gland hypofunction can cause deficient
remineralisation.
• ‘Low buffering capacity and flow rate indicate a greater
erosion risk and advice should be given to the patient to
minimise this.
• This should include following acidic intake with a glass of
water to aid clearance and finishing each meal with a
neutral salivary stimulant, such as cheese, to promote
salivary flow.
• Chewing sugar-free gum also stimulates production of
saliva.
Carranza’s clinical periodontology- 10 th edition

74. 6. Gingivitis
• Lack of saliva leads to retention of food particles in
the mouth, particularly interdentally and under
dentures.
• This may result in gingivitis and, in the long term,
periodontitis.
7. Oral ulceration:
• Reduced saliva flow may result in recurrent
aphthous ulceration, pain, lichen planus, delayed
wound healing and secondary infection, such as
candidiasis.
8. Mucositis:
• This is a painful condition where the mucous
membrane of the oral cavity becomes ulcerated and
inflamed.
• It increases susceptibility to fungal infections such
as candidiasis.
• Mucositis can lead to dysphagia, dehydration and
impaired nutrition.
Oral medicine, Burket’s-11th edition

75. 9. Swallowing
• There are problems with too much saliva or too
little often accompanied by complaints of
dysphagia. (difficulty in swallowing).
10. Dysgeusia
• Distortion of taste may occur due to lack of saliva as
it plays a critical role in taste function as a solvent
for food, a carrier of taste eliciting molecules, and
through its composition.
• This reduces enjoyment of eating.
• In addition, irradiation of the head and neck area
may damage
or destroy taste buds or salivary glands.
Oral medicine, Burket’s-11th edition

76. 11. Glossitis
• With salivary hypofunction, the tongue can appear red, dry and
raw particularly on the dorsum, while the filiform papillae may be lost.
12. Dentures
• Patients with hyposalivation often complain their dentures lose
retention and stability.
• This can cause problems with speech, chewing, swallowing and
nutritional intake.
• It also increases the risk of candidal infections, ulceration, gingivitis,
aspiration pneumonia, bacteraemia, viral infections and caries in the
remaining teeth.
• Denture fixatives may be required to retain the removable prosthesis.
13. Halitosis
• Saliva gives rise to bad odours especially during mouth breathing
prolonged talking or hunger.
• Eating reduces halitosis partly because it increases saliva flow and
friction in the mouth. Oral medicine, Burket’s-11th edition

77. B. HYPERSALIVATION
• The excess secretion of saliva is known as hypersalivation .
• Hypersalivation in pathological condition is known as ptyalism , sialorrhea , sialism or
sialosis.
• Hypersalivation occurs in the following conditions :-
1) Decay of tooth or neoplasm of mouth or tongue due to continuous irritation of nerve
endings in the mouth
2) Disease of esophagus , stomach & intestine
3) Neurological disorder such as cerebral palsy & mental retardation
4) Cerebral stroke
5) Parkinsonism
6) Some psychological & psychiatric conditions
7) Nausea & vomiting
Textbook of Oral Pathology- Shafer, Hine & Levy- 7th edition

78. 1. DROOLING
• Uncontrolled flow of saliva outside the mouth is called
drooling.
• It is often called ptyalism.
• Drooling occurs because of excess production of saliva in
association with inability to retain saliva within the mouth.
• Drooling in small children is a normal part of development.
• Teeth are coming in, they put everything in their little mouths,
and they haven’t developed the habit of keeping the lips
together.
• While child is teething , their gums will produce excessive
saliva.
• The saliva which is produce during drooling is designed to
moisten and lubricate baby’s tender gums.
• Drooling serves to help make teething process more bearable
for child.
MEDICAL PHYSIOLOGY BY SEMBULINGAM 4TH EDITION

79. C. CHORDA TYMPANI SYNDROME
• Chorda tympani syndrome is the condition
characterized by
sweating while eating.
• During the regeneration of the nerve fibers
following trauma or surgical division , which
pass through chorda tympani branch of
facial nerve may deviate & join with the
nerve fibers supplying sweat glands.
Oral medicine, Burket’s-11th edition.

80. D. FREY'S SYNDROME or GUSTATORY SWEATING
• also known as Baillarger’s syndrome, Dupuy’s syndrome, Auriculotemporal syndrome
or Frey-Baillarger syndrome
• It is a food related syndrome which can be congenital or acquired specially after parotid
surgery and can persist for life.
• The symptoms of Frey's syndrome are redness and sweating on the cheek area adjacent
to the ear.
• They can appear when the affected person eats, sees, thinks
about or talks about certain kinds of food which produce
strong salivation.
Oral medicine, Burket’s-11th edition.

81. E. PARALYTIC SECRETION OF SALIVA
• When the parasympathetic nerve to salivary gland is cut ,
salivary secretion increases for the first 3 weeks & later
diminishes; finally it stops at about 6th week.
• The increased secretion of saliva after cutting the parasympathetic nerve fibers is called paralytic
secretion.
F. AUGMENTED SECRETION OF SALIVA
• if the nerve supplying salivary glands are stimulated twice , the amount of saliva secreted by the second
stimulus is more than the amount secreted due to the first stimulus.
• It is because , the first stimulus increases excitability of acinar cells , so that when the second stimulus is
applied the salivary secretion is augmented.
MEDICAL PHYSIOLOGY BY SEMBULINGAM 4TH EDITION

82. EFFECT OF DRUGS & CHEMICAL ON
SALIVARY SECRETION
1) Sympathomimetic drugs like adrenaline & ephedrine stimulates
salivary secretion
2) Parasympthomimetic drugs like acetylcholine , pilocarpine ,
muscarine & physostigmine increase the salivary secretion
3) Histamine stimulates the secretion of saliva
4) Sympathetic depressants like ergotamine depress salivary
secretion .
5) Parasympathetic depressants like atropine inhibit the secretion of
saliva
6) Anaesthetics like chloroform & ether stimulate the reflex secretion
of saliva . However , deep anaesthesia decrease the secretion due
to central inhibition.
Dental Pharmacology By K.D Tripati 6th Edition

83. CONCLUSION
• Saliva has an important role in patient’s quality of life.
• Dental professionals need to be aware of the problems that arise
when there is an overproduction or underproduction of saliva,
and also a change in its quality.
• It may be advantageous for dentists to measure the salivary flow
of patients on a regular basis to see if any changes occur over
time.
• This knowledge enables early diagnosis, treatment and, if
possible, prevention of problems.
• Checking the patient’s medical history regularly can identify
conditions or medications that can adversely influence saliva
production.

84. REFERENCES
1. Orban’s oral histology- 13th edition
2. Tencate’s oral histology- 6th Edition
3. Carranza’s clinical periodontology- 10 th edition
4. Human physiology by A.K. Jain, 5th edition
5. Essentials of medical physiology K. Sembulingum, P. Sembulingum, 4th edition.
6.Oral medicine, Burket’s-11th edition.
7. Textbook of Oral Pathology- Shafer, Hine & Levy- 7th edition
8. Human Antomy By B.D Chaurasia 4th Edition
9. Dental Pharmacology By K.D Tripati 6th Edition
10. The salivary gland fluid secretion mechanism The Journal of Medical Investigation
Vol. 5638 2009
11. Diagnostic Uses of saliva-Mandel I D. Journal of Oral Pathology and Medicine March
1990:19(3);119-25
12. Badruddin et al storage medium for avulsed teeth Indian Journal of Multidisciplinary
Dentistry, Vol. 3, Issue 3, May-July 2013.
13. Kaufman E, Lamster IB. Analysis of saliva for periodontal diagnosis. A review J Clini
Periodontol 2000