IOTN key points

Question 1

MOCDO

Answer 1

missing teeth
overjets
crossbites
displacement of contact points
overbites

Question 2

5i

Answer 2

impacted teeth (except 8s)

Question 3

5h

Answer 3

extensive hypodontia (>1 in a quadrant)

Question 4

5a

Answer 4

OJ >9mm

Question 5

5m

Answer 5

reverse OJ >3.5mm, masticatory and speech difficulties

Question 6

5p

Answer 6

defects CLP and other CF anomalies

Question 7

5s

Answer 7

submerged deciduous teeth

Question 8

hierarchy for grade 5

Answer 8

5i
5h
5a
5m
5p
5s

Question 9

4h

Answer 9

less extensive hypodontia

Question 10

4a

Answer 10

increased OJ >6mm less than or equal to 9mm

Question 11

4b

Answer 11

reverse OJ >3.5mm, no masticatory or speech difficulties

Question 12

4m

Answer 12

reverse OJ >1mm <3.5mm, masticatory and speech difficulties

Question 13

4c

Answer 13

A/P CBs with >2mm discrepancy between RCP and ICP

Question 14

4l

Answer 14

posterior lingual CB with no fct occlusal contact in one or both buccal segments

Question 15

4d

Answer 15

contact displacements >4mm

Question 16

4e

Answer 16

extreme lateral or AOBs >4mm

Question 17

4f

Answer 17

increased and complete OB with gingival or palatal trauma

Question 18

4t

Answer 18

PE teeth, tipped and impacted against adjacent teeth

Question 19

4x

Answer 19

supernumeraries

Question 20

hierarchy for grade 4

Answer 20

4h
4a
4b
4m
4c
4l
4d
4e
4f
4t
4x

Question 21

3a

Answer 21

increased OJ >3.5mm less than or equal to 6mm with incompetent lips

Question 22

3b

Answer 22

reverse OJ >1mm less than or equal to 3.5mm

Question 23

3c

Answer 23

A/P CBs >1mm but less than or equal to 2mm discrepancy between RCP and ICP

Question 24

3d

Answer 24

contact displacements >1mm less than or equal to 3.5mm

Question 25

3e

Answer 25

lat/AOB >2mm less than or equal to 4mm

Question 26

3f

Answer 26

deep OB complete on gingival or palatal tissues, but no trauma

Question 27

hierarchy grade 3

Answer 27

``` 3a 3b 3c 3d 3e 3f ```

Question 28

grade 1

Answer 28

extremely minor malocclusions inc contact displacements <1mm

Question 29

2a

Answer 29

increased OJ >3.5mm less than or equal to 6mm with competent lips

Question 30

2b

Answer 30

reverse OJ >0mm less than or equal to 1mm

Question 31

2c

Answer 31

A/P CB less than or equal to 1mm discrepancy RCP and ICP

Question 32

2d

Answer 32

contact point displacements >1mm less than or equal to 2mm

Question 33

2e

Answer 33

A/P open bite >1mm less than or equal to 2mm

Question 34

2f

Answer 34

increased OB more than or equal to 3.5mm without gingival contact

Question 35

2g

Answer 35

pre-normal or post-normal occlusion with no other anomalies (incs up to half a unit discrepancy)

Question 36

hierarchy grade 2

Answer 36

``` 2a 2b 2c 2d 2e 2f 2g ```

Question 37

what should you do if an occlusal trait is borderline?

Answer 37

assign the lower DHC grade