aetiology malocclusion - skeletal pattern and soft tissues

Question 1

what is skeletal pattern

Answer 1

relationship of upper and lower dental bone

Question 2

3 aspects which influence malocclusion

Answer 2

skeletal pattern
soft tissues
dental causes

Question 3

anterior posterior

Answer 3

front to back

relative position of top jaw and lower jae

Question 4

anterior posterior classes

Answer 4

1

• md set back slightly
• mx and forehead lined up
  2) class 2
• lower jaw set back
  3) class 3
• md set forwards

Question 5

regions of the skull

Answer 5

cranium
cranial base
maxilla
mandible
dental bases

Question 6

aetiology of class 2 skeletal pattern

Answer 6

mx protrusion or md retrusion

Question 7

aetiology of class 3 skeletal pattern

Answer 7

mx retrusion

md protrusion

Question 8

Frankfort plane

Answer 8

lower border of orbit through external auditory meatus

Question 9

average FMP angle

Answer 9

28 degrees

should meet at back of head - Frankfort plane and md plane

Question 10

increased FMP angle

Answer 10

meets infront of the back of head
anterior open bite
steep md angle

Question 11

decrease FMP

Answer 11

deep bite/overbite

meets further back from the head

Question 12

what is the transverse plane used for

Answer 12

checking for growth different between the upper and lower jaws
- can result in cross bites due to discreprency in the widths

Question 13

observing lips

Answer 13

lip length
competent/incompetent
lip line

Question 14

gummy smile lip

Answer 14

vertical maxiallty excess

not always due to shorter upper lip length

Question 15

consequences of incompetent lips

Answer 15

increased risk of trauma fo teeth

Question 16

relationships of lip line - lower lip to upper incisor

Answer 16

normal - lower lip rests in the middle 1/3 upper incisors
low lip line - below lower incisors
high - reteroclined upper incisors
class 2 div 2 - rests over the entire crown of upper incisors

Question 17

tongue thrust

Answer 17

tongue through the teeth to create a seal when swallow eg with anterior open bite

Question 18

effects of digit sucking

Answer 18

• reduced overbite or anterior open bite
• proclines upper incisors
• retro clines lower incisors
• posterior cross bite

Question 19

how to examine labial frenuum

Answer 19

put under tension

blanched on palatal if fibres are going in between teeth

Question 20

what can cause transverse issues/assymertry

Answer 20

Asymmetry can be caused by

• enlargement of one side of the face
• reduce size of one side of the face