Week 11- Fixed Appliances

Question 1

Who developed the first fixed appliance?

Answer 1

Pierre Fauchard

Question 2

What is E-arch?

Answer 2

First fixed appliance developed by Angle, based on Fauchard appliance. Still could only achieve tipping movements.

Question 3

What is pin and tube appliance?

Answer 3

• Band fitted around teeth which were engaged with pins and soldered onto labial arch wire.
• Very difficult to adjust.
• First bodily movement for fixed appliances (couple)

Question 4

What is edgewise appliance?

Answer 4

• Better control of tooth position then ribbon arch
• Basis for modern bracket we still use today.
• Can have backwards, forwards, rotation, tipping, up and down movements

Question 5

What are the movements for edgewise appliance

Answer 5

Back and forwards

Rotation

Tipping

Up and down

Question 6

What are limitations for edgewise appliances?

Answer 6

• High forces used
• Very time consuming to bend first, second and third order movements for each tooth in arch wire

Question 7

What did Tweed and Begg both discover when treating with solely edgewise appliances?

Answer 7

There was relapse when using edgewise system if there was not enough room in arch. Began re-treating cases with premolar exo’s.

Question 8

What are advantages of Begg appliance?

Answer 8

• Low force
• Quick
• Efficient at treating exo cases
• Less time consuming than edgewise appliance.

Question 9

What are bands and bonding?

Answer 9

• Bands are rings encircling a tooth to which attachments are soldered or melded
• Prior to adhesive dental materials
• Now only used for molars (sometimes)

Question 10

What are advantages of NiTi wires?

Answer 10

• Has elastic properties
• Will return to its original shape when bent

Question 11

Andrews 6 keys to normal occlusion*

Answer 11

1. D surface of upper molar occludes with M surface of MB cusp of the lower 2nd molar (molar has to be tipped properly in Angles class I)
2. Correct crown angulation
3. Correct crown inclination (B-L)
4. No rotations
5. Tight contacts (no spaces)
6. Flat occlusal plane

Question 12

What are advantages of straightwire appliance (pre-adjusted edgewise appliance)?

Answer 12

• No more wire bending
• Simple
• Easy to use
• Most popular appliance system today
• Equivalent tx times to Begg

Question 13

What are components of fixed applainces?

Answer 13

Brackets/tubes

Auxillaries

Arch wires

Question 14

What are issues with ceramic brackets?

Answer 14

• Difficult to debond
• High friction
• Brittle
• Tooth wear of opposing teeth

Question 15

What are steps in straightwire appliance?

Answer 15

• Levelling and aligning- NiTi (more flexible and soft)
• Gross tooth movement- stainless steel (more rigid)
• Finishing/detailing- stainless steel

Question 16

How many dimensions are there for rectangular vs round wires?

Answer 16

• Rectangular- 2 sizes
• Round- 1 size

Question 17

What is the Begg Appliance?

Answer 17

• Modified Angle’s ribbon arch bracket and turned it upside down
• Round wires tip crowns into correct position then springs upright roots

Question 18

What is the timeline of fixed appliances?

Answer 18

1. E-arch
2. Pin and tube appliance
3. Ribbon arch appliance
4. Edgewise
5. Begg appliance
6. Straightwire appliance