Operative A2: Instruments And Equipment For Tooth Preparation

Front 1

What are hand held instruments designed to cut?

What materials are they generally made from and what are the downsides?

Back 1

Enamel, dentin, restorative material

Carbon steel - harder, but corrodes more quickly

Stainless steel - loses sharp edge quicker

Front 2

What are the three basic parts of a hand instruments?

Back 2

1) Blade - cuts
2) Shank - connects handle to blade
3) Handle (shaft)

Front 3

What are the four main objectives of having various bends in shanks?

Back 3

1) Better control
2) Better distribution of forces
3) Better access
4) Bring cutting edge to within 2mm of central axis of handle (better balance, instrument won't turn)

Front 4

Greatest control of a hand instrument is gained with what 3 factors?

Back 4

1) Large blade
2) Minimal # of bends in the shank
3) Cutting edge is in direct axial alignment with the shaft or the handle

Front 5

When does an instrument only hav ea three number formula?

What does each number mean?

Back 5

When cutting edge is at a right angle to the long axis of the blade

1st number - width in .1mm
2nd number - length of blade in mm
3rd number - angle of the blade to shaft

Front 6

Four number formula - what does each number mean?

Back 6

1) Width of blade (.1 mm)
2) Angle of primary cutting edge to long axis of handle
3) Length of blade
4) Angle of blade to shaft

Front 7

1) What are chisels primarily intended for?
2) What are they grouped as?
3) Examples?
4) What do you use these instruments for?

Back 7

1) Cutting enamel.
2) Straight, slightly curved, bin shaped.
3) Enamel hatchets and gingival margin trimmers.
4) Plane proximal walls/gingival seats in class IIs

Front 8

1) What are excavators designed for?
2) What are 2 examples of excavators?

Back 8

1) Removing carious dentin
2) Spoon (long blade), discoid (round blade)

Front 9

What grasp permits the greatest delicacy of touch? Describe the grasp.

Back 9

Modified pen grasp. Pads of thumb, second finger, middle grasp, use fourth and tips of ring on nearby tooth surface as rest.

Front 10

High speed instruments:

1) Speed?
2) Used for?
3) Advantages?

Back 10

1) 100-300,000 rpm
2) Gross tooth reduction
3) Remove structure faster, less pressure, vibration, heat

Front 11

Slow speed instruments:

1) Speed?
2) Types of heads?
3) What are they used for?
4) Disadvantages?

Back 11

1) 500-1500 rpm
2) Straight/contra angle
3) Caries removal/prep refinement
4) More pressure, more heat, vibration, skips

Front 12

1) What are burs usually made out of?

2) What are the 3 parts of the bur?

3) Which way are burs supposed to rotate?

4) What is a rake?

5) What is clearance face?

6) What is a rake face?

7) What is an edge angle? What is it related to?

8) What is a clearance angle?

Back 12

1) Tungsten carbide (better than stainless steel, esp. at high speeds)

2) Shank (fits handpiece), neck, head (cutting part)

3) Clockwise

4) Surface of blade that makes contact with tooth structure

5) Opposite side of rake face

6) Angle made by face of blade and radial lone from center of bur perpendicular to surface being cut

7) Angle formed by rake face and clearance face. Resistance of bur to fracture

8) Angle made by back of blade and surface being cut

Front 13

Define:

1) Flute space
2) Concentricity
3) Runout

Back 13

1) Space between bur teeth
2) Measure of whether one blade is longer
3) Accuracy - measures concentricity too, but is more significant because it's a source of vibration

Front 14

Round burs:

1) Where do they cut?
2) What speed do you use them on? Function?
3) #s?

Back 14

1) End and side
2) Slow - remove caries, place retention areas in cavity preps
3) 1/4 to 8

Front 15

Plain fissure burs:

1) Function?
2) #s?

Back 15

1) Cut enamel well, gross tooth reduction at high speed, smooth prep walls at low speed

2) Straight - 50 series
Tapered - 169-171
Tapered with round ends - 1170

Front 16

Cross cut fissure burs:

1) What are they good for?
2) What kind of surface do they leave?
3) #s?

Back 16

1) Enamel reduction at high speed
2) Rough cut surface that needs to be refined
3) Straight - 550 series, tapered = 699-701

Front 17

Inverted cone bur:

1) Where does it cut?
2) What speed is it used at, and what function?
3) #?

Back 17

1) End and side
2) Low, smooth prep floors and place retentive undercuts
3) 30 series

Front 18

Elliptical bur:

1) What shape?
2) #?

Back 18

1) Pear shaped
2) 330

Front 19

Carbide finishing bur:

1) Used for what?
2) What happens when you increase the number of flutes on a bur?

Back 19

1) Finishing procedures (bevel/smooth enamel)
2) Decrease efficiency, increase smoothness

Front 20

Diamond burs:

1) What are the three parts?

Back 20

Metal blank, powdered diamond abrasive, metallic bonding material

Front 21

1) What are mounted stones used for?
2) What are the two most commonly used types?

Back 21

1) Polish amalgam, gold, smooth enamel
2) Green - silicone carbide. White - aluminum oxide