Histology of the Oral Cavity and Salivary glands

Question 1

What is oral mucosa composed of?

Answer 1

• stratified squamous non-cornified epithelium
• underlying connective tissue

Question 2

regions encountering abrasive/shearing forces (especially lips, gingiva and hard palate)have what modification?

Answer 2

a partially cornified to completely cornified modification

Question 3

What are the three major salivary glands? What type are each?

Answer 3

• parotid - serous
  - submandibular- mixed (serous/mucous)

       - sublingual – mucous (largely)

Question 4

What are the salivary products?

Answer 4

salivary amylase

lactoferrin & lysozymes

secretory immunoglobulin – IgA

Question 5

What does salivary amylase do?

How about lactoferrin and lysozymes?

Answer 5

1. breaks down carbs
2. antibacterial activity

Question 6

Where are the minor salivary glands located?

Answer 6

• located in CT elements of oral mucosa

Question 7

What is the largest salivary gland?

What percent of the salivary volume does it account for?

What is the primary product?

Answer 7

The Parotid gland

25%

salivary amylase

Question 8

What type of tissue may be noted in significant amounts in the parotid?

Answer 8

adipose tissue

Question 9

_________:

-accounts for ≈70% of salivary volume

(along with sublingual salivary gland)

• mixed gland, but mostly serous
• contains serous demilunes
• serous cells - salivary amylase

(breaks down carbohydrates)

-mucous cells - secrete mucins

(lubricates food bolus)

Answer 9

Submandibular gland

Question 10

________________:

-accounts for ≈70% of salivary volume

(along with sublingual salivary gland)

• mixed gland (like submandibular)
• but mucous component much larger
• contains serous cells, mucous cells,& serous demilunes

-products same as submandibular gland

Answer 10

Sublingual gland

Question 11

What are the three regions of the lip?

Answer 11

external aspect

vermillion zone

internal aspect

Question 12

_____________:

• always wet
  - stratified squamous wet epi.
  - dense, irregular CT underlying
  - many minor salivary glands
  - (mostly mucous)

Answer 12

internal aspect of lip

Question 13

__________:

• pink region of lip
  - extensive dermal papillae
  - capillary loops impart color
  - devoid of hair & sweat glands
  - need to wet lips with tongue

Answer 13

vermilion zone

Question 14

________________:

• covered with normal (thin) skin
  - continuous with vermilion zone

Answer 14

external aspect of lip

Question 15

What are the 3 calcified substances the tooth is composed of?

Answer 15

Enamel
Dentin
cementum

Question 16

How many sets of teeth do humans have?

Answer 16

2

Question 17

How many deciduous (milk) teeth do we have?

Answer 17

20

Question 18

Describe the two types of adult teeth. How many of each?

How are they distributed?

Answer 18

20 succedaneous teeth
12 molars

-evenly distributed between maxilla & mandible

Question 19

Anatomy of tooth

crown -
root -

      (alveolus –  \_\_\_\_\_\_\_\_\_\_\_\_\_)

cervix -

Answer 19

Anatomy of tooth

crown - visible portion of tooth
root - region housed within alveolus

      (alveolus – bony socket into which tooth fits)

cervix - portion between crown and root

Question 20

Identify

Answer 20

Pulp space/pulp chamber

root canal

Question 21

What passes through the apical foramen?

Answer 21

blood vessels, lymph vessels, nerves

Question 22

what is the periodontal ligament made of? What does it do?

Answer 22

-dense collagenous CT which binds tooth in socket

Question 23

__________:

tough mucous membrane exposed to

strenuous forces

stratified squamous epithelium

(either partially or fully cornified)

dense, irregular connective tissue
principal fiber groups formed by type I

collagen fibers

Answer 23

Gingiva (gums)

Question 24

How are the gums attached to the teeth?

Answer 24

by hemidesmosomes at the enamel surface

Question 25

___________:

• bony, immovable, rigid structure composed of:
  - stratified squamous epithelium
  - cornified or partially cornified
  - dense, irregular collagenous CT
  - anteriorly, displays clusters of adipose cells
  - posteriorly, minor salivary glands (mucous)

Answer 25

Hard Palate

Question 26

_____________:

• stratified squamous noncornified epithelium
• subjacent dense, irregular CT, minor mucous salivary glands

Answer 26

Soft palate

Question 27

_________________: -posterior-most extension of soft palate

Answer 27

Uvula

Question 28

What cell type lines the uvula? What does the uvula contain? (three things)

Answer 28

• lined by stratified squamous non-cornified epithelium
• contains mix of: serous & seromucous glands

                     muscular tissue

Question 29

What are the functions of the uvula?

Answer 29

-helps create several guttural & other sounds

(though not common in English)

-also functions during swallowing

helps prevent reflux into nasal cavity

Question 30

The tongue is highly vascular and contains numerous glands, both serous and mucous. What are the names of these glands?

Answer 30

Mucous – glands of Nuhn

Serous – von Ebner’s glands

Question 31

What are the 4 groups of intrinsic tongue muscles?

Answer 31

superior longitudinal
inferior longitudinal
vertical
transverse

Question 32

The tongue is divided into two regions, describe how. What separates them? One region contains some stuff. Describe it.

Answer 32

• anterior 2/3
  
  • posterior 1/3

      separated by sulcus terminalis
    
      contains deep concavity
    
      foramen cecum

Question 33

Dorsal surface of the tongue is covered by papillae on the anterior 2/3

The lingual papillae classified into four types:

?

?

?

?

Answer 33

• filiform papillae
  - fungiform papillae
  - circumvallate papillae
  - foliate papillae

Question 34

__________________________:

• covered by stratified squamous non-cornified
• red dots distributed among filiform papillae
• color due to blood in subepithelial capillaries

have taste buds on dorsal aspect of “cap”

Answer 34

Fungiform Papillae

Question 35

_________________:

• numerous slender structures
• impart velvety appearance to dorsal surface
• stratified squamous cornified epithelium
• function in scraping food off a surface do not have taste buds

Answer 35

Filiform papillae

Question 36

______________________:

• located along posterolateral aspect of tongue
• appear as vertical furrows
• have functional taste buds in neonate
• taste buds usually degenerate by 2nd or 3rd year of life
• slender ducts of serous minor salivary glands empty into base of furrows
• glands located in core of tongue

Answer 36

Foliate papillae

Question 37

_____________________:

• 8-12, in V-shape anterior to sulcus terminalis
• surrounded by epithelially lined groove
• salivary glands of von Ebner open into groove
• continually wash out groove
• taste buds

  within epithelial lining of groove and side not on dorsum

Answer 37

Circumvallate papillae

Question 38

Taste Buds are Intraepithelial sensory organs that…

• function in perception of taste
• number »3000 on surface of tongue

(& posterior aspect of oral cavity)

• distinctly paler than surrounding epithelium
• oval structure ≈70-80mm long, 30-40mm wide

What kind of cell shape do you find in them? Where does the taste pore open onto?

Answer 38

• each has 60-80 spindle-shaped cells
• taste pore opens onto squamous epithelium

Question 39

Nerve fibers enter taste bud and form synapses with _________ cells

Answer 39

gustatory

Question 40

By what mechanisms are the following taste sensations mediated by?

1. sweet
2. salty
3. bitter
4. savory
5. sour

Answer 40

-Specific ion channels

• Salty
• Sour
• membrane receptors
• sweet
• bitter
• savory (umami)

Question 41

Taste buds able to discern all 5 sensations, but each taste bud specializes in one type of mechanism.

However, complex taste perception is largely a function of what?

Answer 41

largely a function of olfaction

(decreased sensation in persons with congestion)