lever systems

Question 1

actions of muscles

Answer 1

1) functional
- speaking, swallowing, mastication
2) parafunctional
- bruxing, clenching

Question 2

ginglymoarthrodial joint

Answer 2

1) rotates and translates
2) in the foot as well

Question 3

levers

Answer 3

1) make work easier by moving a load around a fulcrum using a force power

Question 4

TMJ

Answer 4

1) class III lever
- least effective

Question 5

occlusal interferences change it to

Answer 5

1) class I lever
- most effective, most destructive

Question 6

class I

Answer 6

1) fulcrum in the middle
2) pivot is between effort and load
3) move a lot of weight without much effort

see saw

Question 7

class II

Answer 7

1) fulcrum in the end
2) load is between pivot and effort
3) work is between fulcrum and power

wheelbarrow

Question 8

class III

Answer 8

1) fulcrum in the end
2) effort is between pivot and load
3) power is between fulcrum and work

fishing rod

Question 9

class III interferences

Answer 9

1) effort is close to molars, which means it is more destructive with a defect on it
2) a tooth located farther anterior will receive less force
3) so if there is a fulcrum on the nonworking side, there is damage done (they normally should not touch when chewing)
4) prematurity in the molar or bicuspid area during a protrusive movement places more stress on the front teeth

– loss of condyle as fulcrum

Question 10

CR/CO occlusal interderence

Answer 10

1) double lever effect
2) prematurity is a lower distal incline causing a forward slide (majority can tolerate it)

Question 11

occlusion rules

Answer 11

1) always important no matter what you do