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Flashcards in Operative Deck (25):
1

How deep should ditching be to consider replacing a restoration?

0.5 mm

2

What do the four numbers on hand instruments represent?

1. Width of the blade in tenths of mm, 2. Primary cutting angle, 3. Blade length in mm, 4. Blade angle

3

What is the rpm range for slow speeds, intermediate speeds, and high speeds?

1. <12,000, 2. 12,000 - 200,000 and 3. >200,000

4

Define Outline form:

Knowing the shape of the restoration and the depth that it should be at

5

Define Primary Resistance form:

Having flat box floors, pulpal floors, etc. The main goal is to avoid any sort of fracture from occlusal forces

6

Define Primary Retention Form:

Shape, height, and form of preparation walls to prevent dislodgement of restoration.

7

Define Convenience Form:

Any alterations that improve access and visibility in restoration

8

Define Secondary Resistance/Retention Forms:

Locks, grooves, coves, etc. - note that they should be placed after the liner

9

What depth should be used for amalgams occlusally?

1.5 mm or 0.2 mm beyond DEJ - whichever is deeper

10

What axial depths should be used for amalgams?

0.2 mm w/o retention locks and 0.5 w/ retention locks

11

What are the two major downsides to using spherical amalgam?

1. Greater leakage and 2. Greater postoperative sensitivity

12

How much percentage of dentin permeability is lost when the smear layer is present?

86%

13

What percentage is the coefficient of thermal expansion for dentin when compared with resin?

1/4

14

How much stress is created by polymerization shrinkage in composites in megapascals?

7

15

What terminology describes the difficulty resin has with polymerization shrinkage when the restoration is large and complex?

C Factor

16

What size are the particles in macrofilled composites?

10 Microns

17

What size are the particles in microfilled composites?

0.04 microns

18

What size are the particles in hybrid composites?

1 micron

19

What size are the particles in microhybrid composites?

0.4 to 0.8 microns

20

What margin (in degrees) is best for gold inlays/onlays?

30-50 degrees (30-40 ideal)

21

Which bur is recommended for gold inlays/onlays?

271

22

What degree of taper should each exit angle have for gold inlays/onlays?

2-5 degrees

23

What bevel width is best for a gold inlay/onlay?

0.5 mm

24

What areas do best with a 40 degree angle in gold inlays/onlays? (4)

1. Occlusal bevel, 2. Groove extension bevel, 3. Secondary flare, and 4. Skirt

25

What areas do best with a 30 degree angle in gold inlays/onlays? (2)

1. Cusp counterbevel and 2. Gingival bevel