9 - Etiology of Malocclusion

Question 1

5% of malocclusions come from what?

Answer 1

Traumas

Question 2

What are predisposing factors to malocclusion?

Answer 2

Genetics
Functional matrix (habits)
Traumas

Question 3

What are the primary etiologic sites for malocclusions?

Answer 3

Bone
Hard tissues

Question 4

What neuromuscular system can cause malocclusions?

Answer 4

Cerebral palsy

Question 5

This affects the number of teeth and makes them pointy

Answer 5

Ectodermal dysplasia

Question 6

What tetragons can interfere with pregnancies?

Answer 6

Alcohol
Drugs
Pollutions

Question 7

This syndrome results from fusion of sutures

Answer 7

Crouzon’s syndrome

Question 8

How can you correct crouzon’s syndrome?

Answer 8

Distraction osteogenesis

Question 9

Crouzon’s syndrome:
A. Premature closure of all sutures
B. Larger orbit
C. Prognatic mandible
D. All of the above

Answer 9

A

Question 10

What are characteristics of Treacher Collins?

Answer 10

1. Underdeveloped cheeks and jawbones
2. Prominent nose, broad mouth, and characteristically small chin with steep lower jaw angle
3. May have cleft lip/palate

Question 11

Does Cleidocranial dysplasia have hypodontia or hyperdontia?

Answer 11

Hyperdontia (extra teeth)

Question 12

What are the characteristics of Cleidocranial dysplasia?
A. Supernumerary teeth
B. Delayed eruption
C. Prognatic mandible
D. All of the above

Answer 12

D

Question 13

What class of malocclusion is associated with Osteogenesis imperfecta?

Answer 13

Class III

Question 14

what malocclusion is associated with osteogenesis imperfecta?

Answer 14

class III

Question 15

Posterior open bite = what class?

Answer 15

Class 3

Question 16

What kind of bite does OI have?

Answer 16

Class III/posterior open bite

Question 17

What are the types of OI?

Answer 17

Type 1
Type III
Type 4

Question 18

What is the best version of OI?

Answer 18

Type 1

Question 19

Do you have midline deviation in OI?

Answer 19

Yes

Question 20

This is one of the most significant aspect of OI

Answer 20

DI

Question 21

If one OI member of the family has DI, then

Answer 21

All other members will have DI

Question 22

If you have type 1 OI, what are the changes you have DI?

Answer 22

20%

Question 23

If you have type 4 OI, what are the chances you have DI?

Answer 23

40-60%

Question 24

If you have type 3 OI, what are the chances you have DI?

Answer 24

100%

Question 25

What are the characteristics of Down syndrome

Answer 25

1. Hypoplasia of midfacial region
2. Class III → posterior open bite

Question 26

Angle classification is based on what relationship?

Answer 26

AP

Question 27

In a normal skeletal relationship, describe the cranial base

Answer 27

Stable for life

Question 28

What is the most common type of malocclusion?

Answer 28

Type 1

Question 29

In what class do you get mandibular retrusion?

Answer 29

Class II

Question 30

Class II malocclusion presents what?

Answer 30

Retrognathic mandible

Question 31

Class III malocclusion presents what?

Answer 31

Maxillary hypoplasia/prognathism

Question 32

What is suggested as the primary cause of class III malocclusion?

Answer 32

Polygenic model

Question 33

Deep bite, Open bite, Cross bite can be caused by what?

Answer 33

1. Transitory
2. Skeletal
3. Neuromuscular imbalance
4. Combination (sleep apnea)