1. Objectives
To be familiar with the anatomy and innervation of the major salivary glands
To be familiar with the functions of saliva, the differences in salival composition among the glands, and to understand the factors that affect salivary flow
To be familiar with the tonsils, their location, and their function

2. Parotid tumor

3. What are salivary glands?
3 major glands:
Parotid
Submandibular
Sublingual
Plus many accessory glands in mucosa
Exocrine glands that secrete directly into the oral cavity
Important for lubricating mouth, remineralizing teeth, breaking down food
Innervated by sensory, parasympathetic, and sympathetic fibres

4. Salivary Glands Overview
Parotid
gland
Sublingual
gland
Submandibular
gland

5. The parotid and other structures

6. Under the parotid

7. The parotid and the mandible

8. Parotid duct and Buccinator

9. Opening to the parotid duct (parotid papilla)

10. Histology of the Parotid Gland
compound racemose gland
large number of ducts arranged in branching system
Mostly serous alveoli with cuboidal- or columnar-lined ducts

11. Summary of the Parotid Largest of the salivary glands
Mostly watery serous secretion
Closely associated with facial nerve and vasculature of the face
Parotid duct opens through cheek above upper second molar
Produces most stimulated saliva

12. Submandibular gland and the mylohyoid muscle
Sublingual gland

13. Openings to the submandibular and sublingal glands
Both glands join common sublingual duct that opens below the base of the tongue in the sublingual papilla.

14. Sublingual papilla

15. Histology of the submandibular gland
Mixed gland with serous and mucous alveoli
Ducts and lobules present, but not as extensive as in parotid
Demilunes are granular serous secreting cells

16. Factors Affecting Salivary Flow
Important Factors
Unimportant Factors
Degree of hydration
Body position
Exposure to light
Olfaction
Previous stimulation
Circadian rhythms
Circannual rhythms
Drugs
Gender
Age (above 15 years)
Body weight
Gland size
Psychic effects
--thought/site of food
--appetite
--mental stress
Functional stimulation

17. Properties of Individual glands
Parotid
Submandibular
Sublingual
Serous
Intermediate
Viscous
High amylase
Low calcium
High calcium
20% unstimulated volume
65% unstimulated volume
7-8% unstimulated volume
50% stimulated volume

18. Innervation of the Salivary Glands
Main control by parasympathetic system:
Submandibular and sublingual: Via chorda tympania of facial nerve through submandibular ganglion
Parotid: Glossopharyngeal nerve via otic ganglion
Sympathetic fibres through cervical ganglion then follow blood vessels to glands

19. Parasympathetic Innervation

20. What are tonsils? Mucosa-associated lymphoid tissue (MALT).
Ring the junction of the oral cavity and orophayrnx and nasal cavity and nasopharynx.
Participate in immune responses to foreign substances inhaled or ingested.
Located in lamina propria of mucosa.
Five tonsils: pharyngeal (adenoid), palatine (x2), lingual (x2).

21. Palatine tonsils

22. Where are the tonsils?

23. Tongue view of tonsils

24. Acute Tonsilitis