oral and nasal cavity

Question 1

locate:

• tubercule
• philtrum
• vermillion border
• labial commissure
• vermillon zone

Answer 1

• tubercule: bump in the middle of upper lip
• philtrum: between upper lip and nose
• vermillion border: left and right side of upper lip
• labial commissure: corner where lips meet
• vermillion zone: middle of upper lip to middle of bottom lip

Question 2

which prominences come from pharyngeal arch 1?

Answer 2

• maxillary

- mandibular

Question 3

define diverticulations

Answer 3

form from outgrowths of nasal cavity

Question 4

what are the four sinuses and when do they form

Answer 4

• maxillary: late pregnancy
• frontal: 2 years old, from the ethmoid sinus
• ethmoid and sphenoid: after birth

Question 5

what is the purpose of a sinus

Answer 5

• humidifies air
• speech
• lightens cranium while maintaining strength

Question 6

describe the lining of the nasal cavity

Answer 6

• pseudostratified columnar epithelium with cilia
• goblet cells which rest on basement membranes
• vascular lamina propia: warms the air

Question 7

how does the paranasal sinus differ from the nasal cavity?

Answer 7

• it is thinner than the nasal mucosa

- fewer goblet cells

Question 8

what are the olfactory epithelium differences?

Answer 8

• bipolar olfactory nerve cells
• formed from ectoderm
• attach to olfactory bulb

Question 9

what is a symphisis

Answer 9

thin line of cartilage that separates 2 bones or cartilage

Question 10

define meckel’s cartilage

Answer 10

cartilage of the first branchial arch associated with the formation of the mandible

Question 11

what happens at the 6 week mark in mandible formation?

Answer 11

• meckels cartilage forms a rod surrounded by a fibrocellular capsule
• the 2 cartilages do not meet at midline, they are separated by a symphisis
• on the lateral aspect of the symphisis, a condensation of mesenchyme forms

Question 12

what happens at the 7 week mark in mandible formation?

Answer 12

• intramembranous ossification begins in the mesenchyme and spreads to form the bone of the mandible
• bone spreads anteriorly to the midline of the developing lower jaw
  
  • bones do not fuse a midline, they are separated by a symphisis
• symphisis fuses shortly after birth

Question 13

where does the mandibular symphisis form from? when does it fuse

Answer 13

• meckels cartilage

- shortly after birth

Question 14

how and when does the ramus develop?

Answer 14

• develops from rapid ossification posteriorly into the mesenchyme of the first arch
• 7 weeks

Question 15

what type of ossification forms the mandible?

Answer 15

intramembranous

Question 16

when does palate formation begin?

Answer 16

6 weeks

Question 17

describe primary palate formation

Answer 17

• median nasal processes fuse and form:
  
  • intermaxillary segment
    
    • median palatine process
    • fuses to form the primary palate

Question 18

what must happen for the oral and nasal cavities to be distinguishable?

Answer 18

the secondary palate must develop

Question 19

what binds the common oronasal cavity anteriorly? what is it occupied by?

Answer 19

• the primary palate

- occupied by developing tongue

Question 20

what makes up the secondary palate?

Answer 20

hard and soft palate

Question 21

what do the maxillary processes form? what direction do they form?

Answer 21

• lateral palatal processes

- fuse from anterior to posterior

Question 22

what outgrowths appear in the oral cavity?

Answer 22

• nasal septum

- two palatine shelves

Question 23

what happens to the nasal septum in the oral cavity?

Answer 23

• grows downward through through the oral cavity

- encounters the primary and secondary palates

Question 24

what is the result of the closure of the secondary palate?

Answer 24

• hardening of the palatine shelves

- vacation of the tongue