Orthodontic therapy

Question 1

Name 3 types of orthodontic appliances

Answer 1

Fixed
Functional
Removable

Question 2

What is proclination?

Answer 2

The upper and lower incisors are inclined labial to a greater degree than normal

Question 3

What is retroclination

Answer 3

The upper and lower incisors are inclined palatal

to a greater extent than normal

Question 4

Name 3 components of a URA

Answer 4

Base plate, retentive components, active components

Question 5

Name the components of a fixed appliance

Answer 5

Brackets
Bands
Ligatures
Archwires
Auxiliaries

Question 6

What is a class I (incisor relationship)

Answer 6

The lower incisal edge occludes below the cingulum plateau of upper incisors.

Question 7

What is a Class II Div I (incisor relationship)

Answer 7

The lower incisal edge occludes behind the cingulum plateau of upper incisors. Upper incisors are usually inclined or proclined and overjet usually increased.

Question 8

What is a Class II Div II (incisor relationship)

Answer 8

The lower incisal edge occludes behind the cingulum plateau of upper incisors. Upper incisors usually retronclined and overbite usually increased.

Question 9

What is a Class III (incisor relationship)

Answer 9

Lower incisal edge occludes anterior to cingulum plateau of upper incisors. Overbite edge to edge or in reverse.

Question 10

What is the curve of spee?

Answer 10

Flat occlusal plane

Question 11

Define the term scissor bite?

Answer 11

One or more buccal segment teeth occlude entirely buccal to the lower arch teeth

Question 12

What amount of force is required intrusion?

Answer 12

10-20gm

Question 13

What amount of force is required for extrusion and tipping?

Answer 13

35-60gm

Question 14

What amount of force is required for bodily movement?

Answer 14

70-120gm

Question 15

What are the limitations of orthodontic treatment?

Answer 15

Medical history
Dental history
Patient compliance
Hypodontia
Tooth size discrepancy
Skeletal discrepancy

Question 16

What are the stages of Orthodontic treatment?

Answer 16

Planning
Active
Retention

Question 17

Describe the sequencing of archwires.

Answer 17

Levelling & aligning
Space closure
Finishing & detailing

Question 18

What is parallax?

Answer 18

The principle of radiographic parallax is employed to determine whether the impacted canine is placed buccal or palatal to adjacent teeth.

Question 19

What force is required for anchorage?

Answer 19

20-25 gm

Question 20

What is anchorage?

Answer 20

The resistance to unwanted tooth movement

Question 21

Explain Newton’s 3rd law

Answer 21

To every action, there is an equal and opposite reaction

Question 22

Name as many methods of anchorage as you can

Answer 22

Transpalatal arch
Nance
Elastics
URA
TAD's (temporary anchorage device)

Question 23

On average how many (mm) reduction in the overjet should we expect per month?

Answer 23

1mm

Question 24

What are TAD’s, and what do they do?

Answer 24

Temporary anchorage device, used as headgear alternative, aid space closure, help create asymmetric arches.

Question 25

Why would you use a NITI coil spring?

Answer 25

Space closure and OJ reduction

Question 26

Name the active components of a removable appliance

Answer 26

``` T/Z Springs (buccal movement) Finger Springs (mesio-distal movement) Labial bow (reduces OJ) Expansion screw (expands maxillary width) Biteplane (reduces OB) ```

Question 27

Name the retentive components of a removable appliance

Answer 27

Adams clasps Cribs Arrowheads

Question 28

List the 6 Andrews Keys

Answer 28

``` Correct molar relationship Correct crown angulation (Tip) Correct crown inclination (torque) No rotations No spaces Curve of spee ```

Question 29

What is abfraction?

Answer 29

Non carious tooth loss, occurs around gingival margin, can occur from traumatic force caused by bruxism

Question 30

Where are the following supernumary teeth located? Mesiondens Distomolar Paramolar

Answer 30

Mesiondens - Maxillary central & incisors (most common supernumary) Distomolar - Distal to 3rd molar Paramolar - buccal or lingual to molar

Question 31

What is hylanisation?

Answer 31

Too much force is used, roots start to resorb, tooth mobility, movement stops

Question 32

What is the 'leeway space'?

Answer 32

Difference in space in the arch when the D's & E's exfoliate and the 4's & 5's erupt.