02 Orofacial Development

Question 1

The palate develops when?

Answer 1

by 9 weeks

cell differentiation forms the lip and the palate

Question 2

Explain merging and an ex of the structure

Answer 2

the center will merge

ex. the tongue

Question 3

Explain fusion and what give an ex of a structure

Answer 3

• Two separate structures will come together and touch, and the cells will go past eachother, integrate, and fuse
• They will have cellular deterioation on their edges as they pass each other from the two separate structures
• Ex. palate, sutures of the skull

Question 4

Branchial arches form when?

Answer 4

27 days

Question 5

What are the 5 pairs of branchial arches?

Answer 5

Mandibular Arch 
    -Also forms the maxilla (and cheeks)
Maxilla 
Hyoid Arch 
Thyrohyoid
4&5 not distinct or named

Question 6

T/F there are midline clefts

Answer 6

False, no midline clefts in the skull or in the nose because it is a single structure

Question 7

at ____ weeks palatal development begins

Answer 7

6 weeks

If the structures are not close together when cellular change takes place the structures will not fuse

Question 8

What 4 structures must fuse during palatal development?

Answer 8

1. the premaxilla
2. palatine process (2)
3. Nasal spine

Question 9

How does fusion occur and how does that impact timing?

Answer 9

• Fusion begins anteriorly and moves posteriorly
• Inherit early or late timing of cellular integration

The window where fusion has to take place is important can affect the fusion

Question 10

the type of cleft depends on what? what types of cleft can arise?

Answer 10

what structures were in place when the window for fusion took place

Ex.Unilateral cleft: it could be that the right palatine shelf fuses with the nasal spine but the left wont
•Most common

Ex.Bilateral cleft: NOTHING came together, the premaxilla and nasal spine are shoved under the nose

Question 11

Palate repair can be done as early as ?

Answer 11

12 months– typically 18 months

Question 12

What is a cleft of the alveolus need?

Answer 12

a bony transplant

Question 13

What is a cleft of the primary plate? vs. secondary plate?

Answer 13

Primary: premaxilla
Secondary: palatine processes and palatine bone

Question 14

What is a submucous cleft?

Answer 14

-The tissue has come together but the muscle hasn’t, so the muscular sling didn’t form and the function of the palate will not work
-Velopharyngeal port will not close so hypernasality will occur because the muscles will not lift and there will be no seal of the velum to the wall
-

Question 15

What are the bones of the hard palate?

Answer 15

the premaxilla, palatine processes of the maxilla, and the palatine bones

Question 16

What does the premaxilla hold?

Answer 16

the four incisors

forms the alveolar ridge that forms the ridge

Question 17

What are the names of all the teeth?

Answer 17

Incisors, cuspids, biscuspids, molars

Question 18

Occlusion means

Answer 18

closure of the teeth

The top molar should be a little behind the bottom molar

Question 19

Maloclussion has to do with placement relationships of the ________

Answer 19

molars

Question 20

What is overjet?

Answer 20

Top 4 front teeth are too far in front and cover the bottom 4

Question 21

What is class I
Class II
Class III occlusion?

Answer 21

Class I: • Crooked teeth but molar relationship is accurate
Class II: • Your typical overbite, the maxilla is too far forward in relation to the mandible
Class III:• The maxilla is too far behind the mandible, retrograde, typical for cleft palate kid, due to abnormal growth in the palate as a whole

Question 22

What is a cross-bite?

Answer 22

•Normally the upper arch overlaps the lower arch
-The upper arch is a just a little further out than the lower arch by roughly a quarter of a tooth
•The upper arch hasn’t formed properly

Question 23

Decidious dentition are?

Answer 23

baby teeth
are lettered
you start on the top right and letter the teeth to the left maxillary posterior arch

Question 24

Misplaced dentition can have a real affect on phonemes (fricatives and affricates) but the biggest affect is on the ___________

Answer 24

velopharyngeal port

Question 25

velar closure a client cannot produce ________

Answer 25

• consonants

- the velopharyngeal port will not close to impound oral pressure

Question 26

What is the primary muscle for velopharyngeal closure?

Answer 26

levator veli palatini

Question 27

What does the superior pharyngeal constrictor do?

Answer 27

takes a part in the velopharyngeal closure

Question 28

what does the musculus uvulae

Answer 28

i. Come together at the center

ii. Participate in pharyngeal constrictor

Question 29

The tensor veli palatini is for what ?

Answer 29

-for Eustachian tube function

why? technically the soft palate is not fused, because the muscle are held together by the raphe
they constantly are evaluated for ear infection

Question 30

When the muscles of the velum are there, in a cleft palate, instead of attaching at the center they will come from where?

Answer 30

the sides!

So when the surgeon fixes the cleft he severs the muscle attachment and must bring them closer towards the front together

i. The resulting velum is often still short to touch the velopharyngeal wall 
ii. But 70% of the time the surgery is effective and function is good