Saliva composition

Question 1

Review the anatomical locations of the 3 major salivary glands

Answer 1

Parotid
• Located in front and beneath the ear
• A duct, called Stensen’s duct, drains saliva from the parotid gland into the mouth
• Opening is on the buccal mucosa of the second maxillary molar
• Serous saliva

Submandibular
• Found on bilaterally, just under and deep to the jaw, towards the back of the mouth
• Produces 70% of the saliva
• The submandibular duct, called Wharton’s duct, enters the floor of the mouth under the front of the tongue
• Mixed saliva

Sublingual
• Reside beneath the tongue, and supply saliva to the floor of the mouth as well
• Mixed saliva

Question 2

List the 5 functions of saliva

Answer 2

• Lubrication and protection
• Buffering and clearance
• Maintenance of tooth integrity
• Antibacterial activity
• Taste and digestion

Question 3

List the 3 types of components that exist within saliva

Answer 3

• Inorganic components: Water and electrolytes
• Organic components: Proteins and protein containing moieties
• Others

Question 4

Describe the 4 roles of water in saliva

Answer 4

• Accounts for 99.5% composition of saliva. Therefore, if there is dehydration, then saliva production is impacted.

4 roles:
• Lubrication and protection
• Maintain tooth integrity (medium to dissolve electrolytes and minerals, physical cleansing)
• Facilitate mastication, swallowing and speech
• Taste and digestion

Question 5

Describe the role of electrolytes in saliva by:

• Listing the 7 electrolytes present in saliva
• Stating the ones involved in buffering pH
• Stating the ones involved in remineralisation

Answer 5

Electrolytes include:
• Osmolarity
• Na+, K+ , Cl- , HCO3, Fl, HPO4 and Ca

Buffering pH 5.75 – 7.05:
• HCO3 (bicarbonate)
• HPO 4 (phosphate)

Tooth integrity:
• Ca2+ (calcium)
• F- (fluoride)

Question 6

List the 13 proteins that are present in saliva

Answer 6

• Mucin
• Proline-rich proteins PRPs
• Amylase
• Lipase
• Agglutinin
• Salivary peroxidase and myeloperoxidase
• Lysozyme
• Lactoferrin
• Immunoglobulins
• Histatin
• Statherin
• Cystatin
• Growth factors

Question 7

List the 7 other components present in saliva

Answer 7

• Gingival cervix fluid
• Blood
• Mucous of the nasal cavity and pharynx
• Microorganisms
• Cells and cell debris
• Food
• Medications or chemicals

Question 8

List the infectious viral (4) and bacterial diseases that spread through saliva

Answer 8

Virus:
· EBV
· Cytomegalovirus
· Flu influenza
· Rhinovirus

Bacteria:
· Streptococcus

Question 9

Discuss how saliva can serve as a diagnostic fluid for systemic diseases

Answer 9

· It is non-invasive, easy to collect and commercially available

Saliva can be used as a diagnostic marker by detecting and analysing things such as: 
· Hormones
· Steroids
· Antibodies
· Growth factors
· Cytokines and chemokines
· Nucleic acids
· Proteins 
· Drugs

Question 10

List the 7 systemic diseases where saliva can be used as a diagnostic marker

Answer 10

· Cardiovascular disease/ MI patients
· Renal disease (dialysis monitoring and detecting CKD)
· Psychological conditions. For example, aggressive behaviour may be indicated by the presence of testosterone
· Autoimmune disorders. For example, in Sjogren’s syndrome, there are self antibodies and antigens
· Infectious diseases
· Malignancies
· Diabetes

Question 11

Describe how saliva is used as a diagnostic marker for CVD and renal disease by stating which salivary components are examined

Answer 11

Cardiovascular disease/ MI patients:
· CRP
· Myoglobin
· Myeloperoxidase

Renal disease (dialysis monitoring and detecting CKD)
Dialysis monitoring:
· Nitrite
· Uric acid
· Cortisol
· Lactoferrin
· Electrolytes
· Amylase

CKD:
· Phosphate (hyperphosphatemia)

Question 12

List the 4 oral diseases where saliva can be used as a diagnostic marker

Answer 12

· Viral infections: EBV, HPV, HSV, HIV, etc
· Bacterial infections
· Fungal infections
· Oral squamous cell carcinoma