Definitions

Question 1

What is orthodontics

Answer 1

Branch of dentistry which deals with correction of dentofacial anomalies & craniofacial malformation.

Question 2

What is occlusion?

Answer 2

Arrangement & position of teeth with upper and lower teeth in contact in their usual position

Question 3

What is ideal occlusion?

Answer 3

Hypothetical concept of perfect arrangement of teeth based on dental anatomy

Question 4

What is normal occlusion?

Answer 4

Minor but acceptable differences from ideal occlusion

Question 5

What is malocclusion

Answer 5

Your teeth position or jaw position outside normal range

Question 6

What causes malocclusion?

Answer 6

General factors:
Skeletal
Soft tissue
Dental (tooth discrepancy)
Habits

Local factors:
Missing teeth
Extra teeth
Abnormal tooth form
Fraenum

Question 7

Name the three planes of space in orthodontics?

Answer 7

Antero-posterior plane: pt assessed profile
Vertical plane: pt assessed profile & frontal
Transverse : pt assessed frontal

Question 8

What is antero-posterior assessment?

Answer 8

Skeletal pattern classification of the relationship of the dental bases which support the teeth & alveolar process

Question 9

Define skeletal class I, II, III

Answer 9

Skeletal cI: Mandible is 2-3mm posterior to the maxilla

Skeletal cII: Mandible is retruded relative to the maxilla

Skeletal cIII: Mandible is protruded relative to the maxilla

Question 10

How would you identify the FMPA?

Answer 10

Average- the line of the FMPA intersects at the occiput

Decreased- the line of the FMPA intersects behind the occiput

Increased-the line of the FMPA intersects infront of the occiput

Question 11

What does BSIC stand for ?

Answer 11

British Standards Institute Classification 1983

Question 12

What is overjet?

Answer 12

Distance between the upper and lower teeth within the horizontal plane

Question 13

What is overbite?

Answer 13

The vertical overlap of the upper incisors over the lower incisors when posterior teeth are in occlusion

Question 14

Difference between incomplete and complete bite?

Answer 14

Incomplete when lower incisors and not touching hard or soft tissue when in occlusion

Complete is when lower incisors are touching hard or soft tissue in occlusion (tooth or palate)

Question 15

Describe average, decreased and increased overbite?

Answer 15

Average- upper incisor cover 1/3 of lower incisor when in occlusion

Decreased- upper incisor cover less than 1/3 of the lower incisor

Increased- upper incisor cover more than 1/3 of the lower incisor

Question 16

What is crossbite?

Answer 16

Upper teeth sits within in the lower teeth when occluding

Buccal cusp in of the lower teeth occlude buccally to the buccal cusp of the upper teeth

Discrepancy in buccolingual relationship of upper and lower teeth

Question 17

What is scissor bite/ lingual crossbite

Answer 17

When the upper dentition sits outside the lower teeth when occluding

Buccal cusp of the lower teeth occlude lingually to the lingual cusp of the upper teeth

Question 18

Definition of Frankfort Plane?

Answer 18

It’s a Plane drawn from the left orbit extending to the external auditory meatus (may-tus)

Question 19

What is a Normal overjet?

Answer 19

2-4mm

Question 20

Give values of crowding ?

Answer 20

0-4mm is mild
4-8mm is moderate
>8mm is severe