Removable appliances I

Question 1

Acrylic plate anterior limit?

Answer 1

1/3 supragingival (3 to 3)

Question 2

Acrlyic plate posterior limit?

Answer 2

1-2mm supragingival up to last molar (EXCEPT 8’s)

Question 3

Acyrlic plate thickness?

Answer 3

2-3mm

Question 4

Spring wire thickness?

Answer 4

0.4mm

Question 5

Spring tipping movement ?

Answer 5

3-4mm

Question 6

V screw? (3)

Answer 6

Anterior/posterior fan expansion

- for triangular arches / anterior crowding

Question 7

Steiner screw?

Answer 7

Bilateral expansion

Combined anteroposterior and transverse expansion

Question 8

Bertoni screw?

Answer 8

3D screw
Unilateral
Anteroposterior and tansverse expansion

Question 9

More loops in a spring means..

Answer 9

More flexible and lighter forces

Question 10

Inclined planes? (2)

Answer 10

• protrude upper and lower incisors

- No retention clasps

Question 11

Cribs? (3)

Answer 11

• Prevents tongue thrust
• Barrier for thumb sucking habit
• Only used for small problems and reliable patients

Question 12

Removable appliance indications? (3)

Answer 12

• small orthodontic movements (less than 5mm)
• Symmetric/asymmetric dentoalveolar compression
• Occlusal interference which prevent dental movement

Question 13

1st week of removable appliance? 2nd?

Answer 13

No activation

From 2nd week onwards, 1/4 turn each week = 0.25mm/week

Question 14

every 1 mm of expansion provides 1mm of..

Answer 14

arch perimeter

Question 15

Saggital cut?

Answer 15

transverse expansion

Question 16

L cut?

Answer 16

Distalization or asymetrical expansion

Question 17

U cut?

Answer 17

Anterior protrusion

Question 18

Y cut?

Answer 18

Transverse and anterior expansion