ACC preps

Question 1

what is the incisal edge reduction?

Answer 1

2.0mm

Question 2

the width of an all-ceramic crown shoulder should be approximately ____mm

Answer 2

1.0

Question 3

there needs to be at lease ___ mm of clearance between the prep and the opposing teeth when in occlusion

Answer 3

1.0mm

Question 4

what does the axial first plane cut establish?

Answer 4

the path of placement/withdrawal for the crown

Question 5

what is the purpose of the labial second plane?

Answer 5

provides a uniform thickness of porcelain over the labial surface

Question 6

the _______ is approximately 1/2 the incise-cervical height of the labial surface after incisal reduction

Answer 6

labial 2nd plane

Question 7

what will excessive angulation of the labial 2nd plane result in?

Answer 7

over-reduction and a thin incisal edge

Question 8

what is the ideal convergence angle of the lingual 1st plane?

Answer 8

8 degree included angle

Question 9

maxillary incisors are inclined nearly _____ degrees to the labial

Answer 9

30

Question 10

the _____________ is 100 degrees to the outer surface of the tooth

Answer 10

cavosurface margin

Question 11

what is the range of acceptable shoulder widths?

Answer 11

1.0-1.2 mm

Question 12

how much is the labial (facial) plane reduced?

Answer 12

1.5mm

Question 13

the lingual first plane is reduced ___ to ___mm

Answer 13

1.0 to 1.2mm

Question 14

the lingual 2nd plane (concavity) must be reduced to allow ____mm clearance

Answer 14

1.0

Question 15

how wide must the labial rounded shoulder be?

Answer 15

1.5mm

Question 16

_________ line angles is critical in ACC preps

Answer 16

rounding

Question 17

which burr is used for the incisal reduction?

Answer 17

256 burr

Question 18

why is a 2.0mm incisal reduction needed?

Answer 18

for good esthetics

Question 19

the shoulder should extend ___mm lingual to the proximal tooth contact area

Answer 19

1.0

Question 20

the shoulder of an ACC prep should be ___mm from the gingiva

Answer 20

0.5

half mm above the gingiva

Question 21

each labial guide groove should be placed to the full depth of what bur?

Answer 21

256 diamond burr

Question 22

the lingual SECOND plane should be reduced with what burr

Answer 22

the 285 (football) burr

Question 23

T/F: the lingual second plane of incisors are prepared flat or slightly concave, while canines have a double concavity

Answer 23

true

Question 24

list the burrs, in order, that are used for inter-proximal reduction

Answer 24

1) 169L carbide
2) 242.6M diamond
3) 256.8M diamond

Question 25

what bur is used to remove the “lip” on the cavosurface margin?

Answer 25

770 diamond

Question 26

where is the “ideal” placement of the cervical margin?

Answer 26

.5mm incisal to the CEJ or the free gingiva (whichever is most coronal)

Question 27

the appropriate path of insertion/withdrawal is 8 degrees from what?

Answer 27

8 degrees from parallel along the long axis of the tooth

Question 28

what is the visual taper of the axial walls on an MCC prep?

Answer 28

6-8 degrees total

3-4 degrees per wall

Question 29

the optimal lingual wall height is ___mm

Answer 29

2