8. Grouping and characterization of hand instruments and engine drive instruments

Question 1

I. Engine drive instruments
1/ What are the 2 groups of engine drive instruments?

Answer 1

1/ Electric driven - Micromotor hand-pieces
2/ Air driven - turbine

Question 2

I. Engine drive instruments
2/ What are the characteristics of Micromotor handpieces?

Answer 2

‣ 40.000 max rpw/min
‣ Speed can be changed by accelerators or reductors
‣ constant power
‣ Direction of rotation can be changed

Question 3

I. Engine drive instruments
3A/ What are the characteristics of turbine?

Answer 3

‣ There are paddles in it’s head
‣ AIR or BALL BEARINGS turbine (ceramic balls)
‣ During the turbine’s working, the air goes between the paddles and opens a channel for outgoing.
* If we stops the handpiece, the paddle closes the coming air.
‣ 450.000-500.000 rpm/min Compressed air
‣ Ball bearings
‣ Friction grip attachment
‣ Performance related !
‣ Connected to the clutch
‣ Direction of rotation can’t change

Question 4

I. Engine drive instruments
3B/ What are the 2 types of turbine?

Answer 4

1/ Cooling
◦Prevent overheating of the pulp
◦The abraded material is removed

2/ Light
◦Illuminating the treatment site
◦Fiber optic system
◦LED or halogen lamps

Question 5

I. Engine drive instruments
3C/ What are the characteristics of cooling turbine?

Answer 5

◦Prevent overheating of the pulp
◦The abraded material is removed

Question 6

I. Engine drive instruments
3D/ What are the characteristics of light turbine?

Answer 6

◦Illuminating the treatment site
◦Fiber optic system
◦LED or halogen lamps

Question 7

I. Engine drive instruments
4. Classification of straight handpieces?

Answer 7

blue ring – 1:1
red ring 1:5
green ring 5:1

Question 8

I. Engine drive instruments
5A. Classification of burs

Answer 8

Burs: classified with letters for:
Form, shape, length of head, shank, material, coarseness