SALIVA AS A DIAGNOSTIC TOOL - DEFINITION - PROPERTIES OF SALIVA - COMPOSITION - FUNCTION OF SALIVA - PRODUCTION OF SALIVA - REGULATION OF SALIVARY SECRETION - APPLIED PHYSIOLOGY - COLLECTION METHOD AND DEVICE - DIAGNOSTIC APPLICATION - CONCLUSION - REFERENCES

1. SALIVA AS A DIAGNOSTIC
TOOL
GUIDED BY PRESENTED BY
DR. SHALU RAI (HEAD AND PROFESSOR) - DR. PRIYANKA
DR. DEEPANKAR MISRA (PROFESSOR)
DR. PUNEET BHATNAGAR (READER)
DR. MUKUL (READER)
DR. SAHIL KIDWAI (SENIOR LECTURER)
DR. SUMAN BISLA (SENIOR LECTURER)

2. CONTENTS
• Definition
• Properties of saliva
• Composition
• Function of saliva
• Production of saliva
• Regulation of salivary secretion
• Applied physiology

3. • Collection method and device
• Diagnostic application
• conclusion
• References

4. Definition
• By Stedmann’s & Lipincott medical dictionary.
A clear, tasteless, odourless, slightly acidic (pH 6.8) viscous fluid, consisting of the
secretion from the parotid, sublingual, submandibular salivary glands and the
mucous glands of the oral cavity.

5. PROPERTIES
• Volume:
• 1000 to 1500 mL per day and, it is approximately about 1 mL/ minute.
• Contribution by each major salivary gland is:
• i. Parotid glands: 25%
• ii. Submandibular glands: 70%
• iii. Sublingual glands: 5%.
Essentials of physiology for dental student , k sembulingum 2nd edition

6. Reaction: Mixed saliva from all the glands is slightly acidic with pH of 6.35 to 6.85.
Specific gravity: It ranges between 1.002 - 1.012.
Tonicity: Saliva is hypotonic to plasma.
Essentials of physiology for dental student , k sembulingum 2nd edition

7. COMPOSITION
• Mixed saliva contains
99.5% water and
0.5% solids

10. SALIVARY FLOW
• The average person produces approximately 0.5 L – 1.5 L per day
• Unstimulated Flow (resting salivary flow―no external stimulus)
Typically 0.2 mL – 0.3 mL per minute
• Stimulated Flow (response to a stimulus, usually taste, chewing, or medication
[eg, at mealtime])
Typically 1.5 mL – 2 mL per minute

11. FUNCTION OF SALIVA
Ten Cate’s Oral Histology

12. ROLE IN SPEECH
• By moistening and lubricating soft parts of mouth and lips, saliva helps in
speech.
• If the mouth becomes dry, articulation and pronunciation become difficult.
Ten Cate’s Oral Histology

13. Excretory function
• Many substances, ( organic and inorganic).
• In some pathological conditions, saliva excretes certain substances, which are not
found in saliva under normal conditions such as glucose in diabetes mellitus.
• In certain conditions, some of the normal constituents of saliva are excreted in
large quantities.
For example, excess urea - nephritis, and
excess calcium - hyperparathyroidism.
Ten Cate’s Oral Histology

14. Regulation of salivary secretion

16. • Sympathetic fibers
• The sympathetic preganglionic fibers to salivary glands arise from the lateral
horns of first and second thoracic segments of spinal cord.
• The fibers leave the cord through the anterior nerve roots and end in superior
cervical ganglion of the sympathetic chain.
• The postganglionic fibers from this ganglion are distributed to the salivary
glands along the nerve plexus around the arteries supplying the glands.
• Essentials of physiology for dental student , k sembulingum 2nd edition

17. Formation of saliva
• acinar cells produce initial saliva composed of water, ions, enzymes, and mucus
• initial saliva is isotonic
• initial saliva passes from acinus to duct
• ductal cells modify initial saliva to produce final saliva by altering various
electrolyte concentrations
• ductal cells absorb Na+ and Cl- , decreasing ion concentrations in saliva

18. • ductal cells secrete K+ and HCO3 - , increasing ion concentrations in saliva
• salivary HCO3 - neutralizes oral bacterial acids
• maintains dental health
• final saliva is hypotonic
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

19. APPLIED PHYSIOLOGY
Hyposalivation
• The reduction in the secretion of saliva is called hyposalivation.
• It is of two types, namely, the temporary hyposalivation and the permanent
hyposalivation.
• 1. Temporary hyposalivation occurs in: i. Emotional conditions like fear ii. Fever
iii. Dehydration.
• 2. Permanent hyposalivation occurs in: i. Obstruction of salivary duct
(sialolithiasis) ii. Congenital absence or hypoplasia of salivary glands iii.
Paralysis of facial nerve (Bell’s palsy).
• Essentials of physiology for dental student , k sembulingum 2nd edition

20. Dentures:
• patients with hyposalivation often complain their dentures lose retention and
stability. This can cause problems with speech, chewing, swallowing
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.

21. Hypersalivation
• The excess secretion of saliva is known as hypersalivation.
• The physiological condition when hypersalivation occurs is pregnancy.
• Hypersalivation in pathological conditions is called ptyalism, sialorrhea(
cerebral palsy, Parkinson’s disease )

22. 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.
• Loss of gland function occurs after radiation therapy for head and neck cancer.
• Temporary relief is achieved by frequent sipping of water or artificial saliva .

23. Chorda Tympani Syndrome
• Chorda tympani syndrome is the condition characterized by sweating while
eating.
• During trauma or surgical procedure some of the parasympathetic nerve fibers
to salivary glands may be severed.
• And, during the regeneration some of these nerve fibers, which run along with
chorda tympani branch of facial nerve may deviate and join with the nerve fibers
supplying sweat glands.
• Essentials of physiology for dental student , k sembulingum 2nd edition

24. FREY'S SYNDROME or GUSTATORY SWEATING
• also known as Auriculotemporal syndrome
• characterized by flushing and sweating of facial skin along the region of
distribution of auriculotemporal nerve.
• 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.

25. Sjogren’s syndrome
• - chronic autoimmune disease characterized by symptoms of oral and ocular
dryness, exocrine dysfunction, lymphocytic infiltration, and destruction of
exocrine glands.
• Primary Sjögren’s syndrome occurs in the absence of another autoimmune
disease, whereas secondary SS occurs in the setting of autoimmune diseases such
as systemic lupus erythematosus, rheumatoid arthritis, and scleroderma.
• This triad is also known as the sicca complex.
• Oral medicine Burkitt 12th edition

26. 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 occurs in the following conditions:
i. During teeth eruption in children
ii. Upper respiratory tract infection or nasal allergies in children
iii. Difficulty in swallowing
iv. Tonsillitis

27. SALIVA COLLECTION METHODS AND DEVICES
• There are two methods of saliva collection:
• Passive Drool
• highly recommended because it is cost effective.
• To avoid introduction of contaminants, use only high-quality polypropylene vials
for collection, such as our 2 ml Cryovials.
• The vials used must be sealed tightly and should be able to withstand temperatures
as low as −80°C.
• https://youtu.be/ou2dbZN0Oiw
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

28. 2. The Salimetric Oral Swab (SOS)
• samples are to be analyzed for cortisol, testosterone, α-amylase, C-reactive
protein (CRP), or salivary secretory immunoglobulin A (SIgA).
• helps to filter mucus and other matter from the sample(no precipitate and
improve the immunoassay results).

29. • Gloves - avoid deoxyribonucleic acid contamination.
• made of a non-toxic, inert polymer shaped into a 30 mm × 10 mm cylinder.
• ordered with a Swab Storage Tube which consists of a capped, conical centrifuge
tube with a separate insert that allows saliva to be centrifuged into the bottom of
the conical tube.
• If centrifugation is not available, saliva from the swab may be expressed into a
Cryovial using a needleless 5 cc plastic syringe
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

30. • SCS ( Salimetrics children swab )- <6 years, and the SIS (Salimetrics Infant swab) < 6
months of age.
• made of the same inert polymer but they are manufactured in longer lengths, which
allow one end to be held by a parent or technician while the other end is placed in
the child’s mouth.
• The diameters of the SCS and SIS are appropriate for the size of the children’s
mouths, 8 and 5 mm, respectively.
• The polymer used for the swabs is very durable and can withstand chewing by the
child, and its taste and texture are also acceptable to children.
• The volume of sample recovered from the SCS and SIS is typically in the range of
200–1000 µL.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

31. Protection and Storage of Saliva
• To protect unstable saliva, there should be no bacterial growth, and to prevent
bacterial growth, the samples should be maintained at 4°C before uses.
• After freezing, centrifugation is done which also helps to precipitate mucins present
in the samples and will make pipetting much easier.
• During testing, saliva should be assayed, first saliva should be brought to the room
temperature, and then saliva should be centrifuged for 15 min at approximately 3,000
RPM.
• All tests should be performed only using clear saliva.
• Saliva should be devoid of any sediment present in the bottom of the tube.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

32. DIAGNOSTIC APPLICATION OF SALIVA
• Oral Oncology
• Oral cancer can develop in any part of the oral cavity with a 5-year survival rate
of 40–50%.
• diagnosed by difference in certain proteins present in saliva such as M2BP,
MRP14, CD 59, genomic markers such as dual specificity phosphatase 1, H3
histone family 3A, interleukin-1β (IL-1β), IL-8 and salivary microbiota.
• Sometimes, DNA and RNA can be present in saliva which is a indication for oral
cancer.

33. • Certain microorganism level increases in saliva of oral cancer patients.
• Porphyromonas gingivalis, Tannerella forsythia, and Candida albicans will
increase in number of oral cancer patients.
• Prevalence of Streptococcus sobrinus in healthy group was significantly lower
than in head and neck tumor patients.
• Significantly elevated levels of P. gingivalis, Prevotella melaninogenica, and
Streptococcus mitis saliva of oral cancer patients can be used as a diagnostic tool
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

34. • Viral Diseases
• Saliva is more sensitive and specific in testing for HIV infection, human herpes
virus, cytomegalovirus, Epstein–Barr virus, and hepatitis C virus.
• SIgA, which is formed from plasma cells present in the salivary glands.
• Antibodies against viruses and viral components can be detected in saliva and
can help in the diagnosis of viral infections.
• SIgA levels in HIV patient decline as the patients become symptomatic.
• Hence, it can be used as a prognostic indicator for the detection of HIV infection.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

35. • Dental Caries
• If a person has caries, then the person may also have low salivary production. Saliva
removes the dietary component and microorganisms from the oral cavity.
• Certain study shows that salivary parameters such as salivary flow rate, salivary
viscosity, salivary pH, and salivary buffering capacity were lower in subjects with
high dental caries.
• Hence, salivary testing is recommended as a part of routine diagnosis when treating
patients with high dental caries risk.
• Saliva based caries activity test includes Lactobacillus colony count test, Snyder test,
reductase test, buffer capacity test, Fosdick calcium dissolution test, Streptococcus
mutans adherence method, and S. mutans dip-slide test.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

36. • Cardiovascular Disease
• The most common cardiovascular disease is acute myocardial infarction, which
is commonly known as heart attack.
• Acute myocardial infarction is caused due to the accumulation of lipid in the
walls of arteries.
• Salivary amylase level analysis is used in the post-operative control of patient
who has undergone cardiovascular surgery.
• detected by the rise and/or fall of salivary cardiac troponin (cTn) levels.
• cTn in saliva can be used to detect acute myocardial infarction, but it has a poor
diagnostic capability.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

37. Autoimmune Diseases
• In patients with Sjögren’s syndrome, increased levels of rheumatoid factor,
antinuclear antibody, anti-SS-A, and anti-SS-B antibody, increased concentrations
of sodium and chloride, IgA, IgG and albumin, and a decreased concentration of
phosphate were reported in the saliva of patients
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

38. Diabetes Mellitus
• A significant correlation found between fasting blood glucose and fasting
salivary glucose, and glycosylated hemoglobin for both diabetic and healthy
control groups supports the use of saliva as a diagnostic fluid in Type II diabetes
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

39. Saliva in Forensics
• Saliva may be found on victims of several violent crimes; aberrant genetic
material (DNA) and the mRNA that helps process the genetic information into a
protein from cells can also be detected in saliva. It can potentially be recovered
from bite marks, cigarette butts, postage stamps, envelopes, and other objects.
During the biting process, saliva is deposited on skin or object surface which
allows enough amount of saliva for typing DNA
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

40. Stress and Depressive Disorders
• Increased salivary cortisol levels can be used as an indicator of stress.
• Cortisol levels increased significantly during the captivity experience and
peaked following interrogation.
• Testosterone levels were significantly reduced within 12 h of captivity.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

41. • Patients with affective disorders secrete significantly less saliva than normal.
• In the saliva of patients with major depressive disorders, the concentrations of
immunoreactive prostaglandins are significantly higher than those of healthy
controls.
Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar

42. Periodontal disease
• Periodontal diseases have been associated with increased levels of aspartate
aminotransferase (AST) and alkaline phosphatase (ALP).
• Salivary AST can be used as a marker for monitoring periodontal disease.
• Lower levels of uric acid and albumin were associated with periodontitis

43. COVID-19
• previous study examined the SARS-CoV loads in different clinical samples and found
that the virus RNA could be detected in saliva (5.2 x 102 copies/mL), although its level
was relatively lower than that in throat swabs (5.5 x 102 copies/mL), sputum (1.2 x
106 copies/mL), and endotracheal aspirates (2.8 x 106 copies/mL).
• saliva is of potential diagnostic value for and should play a role in detection of SARS-
CoV-2 infection.
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7526585/

44. CONCLUSION
• Saliva is considered as the mirror of our body.
• Saliva contains many proteins which are altered in diseased state and can be
used as a key to diagnose the disease.
• Salivary diagnosis of disease is useful because it is noninvasive, easy to collect,
readily available, and cost-effective than other diagnostic methods.

45. References
• Essentials of physiology for dental student , k sembulingum 2nd edition
• Saliva as a diagnostic tool: A review Ilakkiya Ezhil , G. Savitha , M. P. Santhosh Kumar
• Ten Cate’s oral histology
• Oral medicine Burkitt 12th edition
https://youtu.be/ou2dbZN0Oiw
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7526585/