Occlusion and Malocclusion

Question 1

Define ideal occlusion

Answer 1

Anatomically perfect arrangement of teeth

Question 2

Define normal occlusion

Answer 2

Acceptable variation from ideal occlusion

Question 3

List 4 point about normal occlusion

Answer 3

no crowding
teeth are well aligned
class I incisor relationship
class I molar relationship

Question 4

Define Class I incisor relationship

Answer 4

The incisal edges of the lower incisors occlude with or lie immediately below the cingulum of upper central incisors

Question 5

Define Class I molar relationship

Answer 5

The mesio-buccal cusp of the maxillary 1st molar occludes in line with the buccal groove of the mandibular 1st molar
the maxillary 1st molar is positioned slightly posterior in relative to the mandibular 1st molar

Question 6

define malocclusion

Answer 6

variation from ideal occlusion which has dental and/or physiological implications

Question 7

How many classes of malocclusions are there?

Answer 7

3

Question 8

Define Class I malocclusion

Answer 8

Bite is normal but upper teeth slightly overlap the lower teeth

Question 9

Define Class II malocclusion

Answer 9

upper teeth severely overlap the bottom teeth

MB cusp of max 1st molar more mesially placed

Question 10

define Class II div I malocclusion

Answer 10

class 2 molars with normally inclined or proclined maxillary central incisors

Question 11

define Class II div II malocclusion

Answer 11

class 2 molars with retroclined maxillary incisors

Question 12

what does a class II div I malocclusion increase?

Answer 12

overjet measurement due to proclined incisors

Question 13

define class III malocclusion

Answer 13

lower jaw protrudes forward

MB cusp of max 1st molar distally positioned

Question 14

define overjet

Answer 14

horizontal distance between upper and lower incisors

Question 15

define overbite

Answer 15

upper teeth overlap lower teeth

Question 16

name 3 genetic causes of malocclusions

Answer 16

skeletal pattern
size of jaws and teeth
certain syndromes

Question 17

how many classes of skeletal classes are there?

Answer 17

3
Class I
Class II
Class III

Question 18

what are the 3 dimensions of clinical examination?

Answer 18

antero-posterior
transverse
vertical

Question 19

name 2 ways the face can be assessed vertically?

Answer 19

using the rule of thirds

measuring the angle of the lower border of the mandible to the maxilla

Question 20

how can the face be assessed transversely?

Answer 20

facial symmetry

Question 21

name a genetic syndrome that can cause a malocclusion?

Answer 21

cleft lip and palate

Question 22

name the 5 environmental causes of malooclusion

Answer 22

soft tissues- 
habits- 
pathology- tumour 
trauma- intrusion
Local factors

Question 23

name an environmental ST factor

Answer 23

incompetent lips

Question 24

name a habit that causes malocculsion

Answer 24

thumb sucking

Question 25

name 5 environmental local factors that can cause malocclusions

Answer 25

supernumerary teeth
hypodontia
fraenum
retained deciduous tooth
early loss of deciduous tooth

Question 26

define mesiodens

Answer 26

supernumerary teeth between the upper central incisors

Question 27

what problems can mesiodens cause?

Answer 27

prevent other teeth from erupting

Question 28

define midline diastema and what can cause this

Answer 28

space/gap between maxillary central incisors

can be caused by the fraenum

Question 29

how can a retained deciduous tooth cause problems?

Answer 29

can prevent permanent tooth erupting into correct position

Question 30

what is the problem with early loss of deciduous teeth?

Answer 30

loss of space- other teeth may erupt/move into this position disrupting the ‘normal’ eruption process

Question 31

what does IOTN stand for

Answer 31

index of orthodontic treatment need

Question 32

what are the 2 components of IOTN

Answer 32

dental health component- severity of treatment need graded 1-5 1=no treatment
aesthetics component- 10 pictures

Question 33

what is the problem with the aesthetics component

Answer 33

subjective