Biological Principles of Ortho Tooth Movement

Question 1

These bone cells are found ahead of the drifting tooth where there’s resorption.

Answer 1

Osteoclasts.

Question 2

Osteoclasts create these kinds of margins.

Answer 2

Scalloped

Question 3

Osteoclasts are on the pressure or tension side?

Answer 3

Pressure

Question 4

This kind of bone is deposited on the tension side, then it’s filled with calcium salts.

Answer 4

Osteoid

Question 5

These bone cells are deposited behind the drifting tooth.

Answer 5

Osteoblasts

Question 6

This type of bone is more resistant to resorption

Answer 6

Osteoid

Question 7

Hyperemia on a tooth is caused by what?

Answer 7

Slight force on the tooth.

Question 8

Effects of severe forces on dentin and cementum.

Answer 8

May perforate the cementum layer, causing dentin resorption.

Question 9

These cells repair dentin after active tooth movement.

Answer 9

Cementoblasts.

Question 10

Be cautious of this in enamel with active tooth movement.

Answer 10

Decalcification

Question 11

When you try to tip a tooth lingually, where is there the greatest resorption?

Answer 11

Palatal crest

Question 12

There’s an increased periodontal membrane thickness where?

Answer 12

Apically, past the center of rotation.

Question 13

Most compression of the PDM is seen where in a lingually tipped incisor?

Answer 13

At the alveolar crest

Question 14

Optimum force on a tooth is slightly above what?

Answer 14

Capillary pressure

Question 15

Optimum force on a tooth compresses the PDM by what fraction on the pressure side?

Answer 15

1/3

Question 16

The PDM can be crushed (pressure side) or torn (tension side) is there’s this kind of pressure.

Answer 16

Excessive

Question 17

The range of optimum force for ortho movement.

Answer 17

50-200 grams

Question 18

Where is a tooth’s center of resistance?

Answer 18

On the root

Question 19

Forces have to be directed here in order for the toop to translate, and NOT tip.

Answer 19

Center of mass/rotation

Question 20

Tipping movements of teeth are mostly done with these kinds of appliances.

Answer 20

Removable

Question 21

Bodily movement is also known as what?

Answer 21

Translation

Question 22

What kind of forces are needed for pure rotation of a tooth?

Answer 22

Equal and opposite

Question 23

Bodily movement is mostly done with these kinds of appliances.

Answer 23

Fixed

Question 24

Bodily movement of a tooth applies forces where?

Answer 24

In more than one point

Question 25

This type of force slows orthodontic tooth movement because osteoid is deposited on the pressure side during recovery.

Answer 25

Intermittent light force

Question 26

The ideal force in ortho for tooth movement.

No osteoid bone is formed.

Answer 26

Continuous light

Question 27

Elastic fibers located here reorganize SLOWLY.

Answer 27

Alveolar crest

Question 28

A beam that’s fixed at only one end.

Answer 28

Cantilevered beam

Question 29

The simplest spring.

Answer 29

Cantilevered beam

Question 30

The displacement of a spring is directly proportional to the load/force.

Answer 30

Hooke’s Law of Elasticity.

Question 31

Resistance to bending.

Answer 31

Stiffness

Question 32

When the object goes back to its unstretched state.

Answer 32

Unloading

Question 33

Absorbs energy

Answer 33

Loading

Question 34

Releases energy

Answer 34

Unloading

Question 35

Stiffness increases as length _______.

Answer 35

shortens

Question 36

Stiffness increases as diameter _______.

Answer 36

increases

Question 37

The maximum force to which something can be stretched so you don’t permanently deform it.

Answer 37

Elastic Limit

Question 38

High modulus means what?

Answer 38

Stiff

Question 39

Low modulus means what?

Answer 39

Elastic

Question 40

Deflection up to the elastic limit.

Answer 40

Range of activation.

Question 41

How do loops and helices affect stiffness?

Answer 41

Reduce stiffness