Fixed ortho

Question 1

What are the 6 keys of andrews?

Answer 1

Class 1 incisors
Class 1 molars
Flat occlusal plane or minimal curve of spee
Long axis of teeth have slight mesial inclination except lower incisors
Tight occlusal contacts with no rotations
Crowns of canines back to molars have slight mesial inclination

Question 2

What are the advantages of fixed appliances?

Answer 2

Can fix rotations
3D control
Control of root movement
Less dependent on patient compliance

Question 3

What are disadvantages of fixed appliances?

Answer 3

Requires excellent OH
Poor intrinsic anchorage
Risk of iatrogenic damage

Question 4

What are the features of nickel-titanium archwires?

Answer 4

Flexible
Light continuous force
Shape memory - return to original shape - cannot bend
Higher friction than stainless steel

Question 5

What are the features of stainless steel archwires?

Answer 5

Low friction
Formable - able to form arch-wire bends or loops

Question 6

What are slide-mechanic, force-generating components?

Answer 6

Elastic power chain
NiTi coil springs
Intra-oral elastics
Active ligature

Question 7

What is a TAD?

Answer 7

Temporary anchorage devices - non-osseo-integrating mini screw
Non-osseo-integrating prevents ankylosis

Question 8

How does a TAD provide anchorage?

Answer 8

Need a PDL surrounding the tooth to be able to move it - no PDL surrounding TAD so does not move

Question 9

What is absolute anchorage?

Answer 9

Pulling against something you know won’t move because there is no PDL surrounding that allows for that - TAD

Question 10

What is intermaxillary anchorage?

Answer 10

When anchorage units situated in one jaw are used to provide the force required to move teeth in opposing jaw - done with ELASTICS