Power Scalers

Question 1

What converts electric or pneumatic energy into a mechanical vibration?

Answer 1

Power scalers

Question 2

What happens when the power scaler is placed against the calculus?

Answer 2

Vibration shatters it

Question 3

What is the range of cycles per second the power scaler operates in?

Answer 3

8000 to 45,000

Question 4

What are the three types of power instruments?

Answer 4

Ultrasonic scaler

Sonic and rotary instruments

Question 5

What does the ultrasonic scaler do?

Answer 5

Converting sound waves into a mechanical vibration

Question 6

What do the sonic and rotary instruments do?

Answer 6

Convert air pressure into mechanical vibration

Question 7

How do ultrasonic instruments work?

Answer 7

By converting energy from a power source into a sound wave

Question 8

Where is the sound wave picked up?

Answer 8

At the handpiece

Question 9

What are the two type of devices in the handpiece that can pick up the sound wave and turn it into a vibration?

Answer 9

Magnetostrictive and Piezoelectric

Question 10

Which handpiece uses either a ferroceramic rod or metal strips?

Answer 10

Magnetostrictive

Question 11

What do the flat metal strip units vibrate at?

Answer 11

18,000 cycles per second
25,000 cycles per second
30,000 cycles per second

Question 12

Why are lower amplitudes better?

Answer 12

Because they cause less damage to the tooth

Question 13

These instruments have an amplitude of what?

Answer 13

0.01 and 0.05 mm

Question 14

What are the ultrasonic and combination motor handpieces used for?

Answer 14

Polishing and simple cutting of teeth

Question 15

These instruments have an amplitude of what?

Answer 15

0.01 to 0.02 mm with a circular-type motion

Question 16

If using an inserting ultrasonic unit what must be filled before the insertion of the insert?

Answer 16

The handpiece

Question 17

If using a ferroceramic rod unit, what must be drained before insertion of the insert?

Answer 17

The handpiece

Question 18

What happens if the insert is forced into a hand-piece that contains water?

Answer 18

It may prevent the insert from vibrating or cause the tip to fracture

Question 19

What do piezoelectric ultrasonic scalers use in the handpiece to pick up the vibration?

Answer 19

Crystals

Question 20

What is the frequency and amplitude of the piezoelectic units?

Answer 20

25,000 to 45,00 cycles per unit

Amplitude 0.2 mm

Question 21

What does the amplitude of 0.2 mm in a piezoelectric unit result in?

Answer 21

Wide, back-and-forth tip motion

Question 22

Is the vibration energy of a piezoelectric unit distributed evenly down the tip?

Answer 22

No

Question 23

The motion of the piezo tip is not uniform, the tip moves farther in one direction than in the other, what does this mean?

Answer 23

That during use the most active side of the tip must be placed on the part of the tooth where the calculus is to be removed

Question 24

What is the most popular and effective solution placed in the containers?

Answer 24

0.12% chlorhexidine

Question 25

What was the first type of tip developed, is relatively wide and is used for supragingival cleaning?

Answer 25

The beaver-tail tip

Question 26

What is a thin tip and can be used subgingivally?

Answer 26

The “perio probe”

Question 27

Which tips hook to the left or right, which allows them to gain access to furcations around crowns and be used subgingivally?

Answer 27

The Furcation tips

Question 28

What is the frequency and amplitude that sonic scalers operate at?

Answer 28

6000 cycles per second

0.5 mm amplitude

Question 29

What is the motion of sonic cleaners?

Answer 29

Elliptic, a figure-of-eight motion

Question 30

What is one feature of a sonic scaler?

Answer 30

The compressed air has a cooling effect

They are less likely to cause heat-related damage to the teeth than ultrasonic scalers

Question 31

Why is the use of rotary scalers discouraged?

Answer 31

Rotary scalers can easily damage the tooth

Burs must be replaced often because they become dull extremely quickly