Class V Cavity Preparations

Question 1

class V lesions involve ____ apical to the height of contour on the ___ and ____ surfaces of all teeth

Answer 1

smooth surfaces; facial; lingual

Question 2

class V preps are at the ____ of the facial and lingual of the crowns due to lesions (carious and non carious)

Answer 2

gingival 1/3

Question 3

Clinically, the shape and the size (outline form) of class V cavity preparation depends on

Answer 3

1- extent of the lesion
2- preexisting restoration
3- location of the lesion
4- restorative material of choice

Question 4

characteristics of ideal/small lesions / classical more conservation preparations

Answer 4

cervical/apical to height of contour
confined between mesial and distal line angles
do not extend to the cemento-enamel junction

Question 5

characteristics of non-ideal lesions/modified

Answer 5

extends to height of contour/occlusal to HOC
extension into mesial and distal
extension to become root surface caries

Question 6

amalgam requires:

Answer 6

• butt joint margin
• uniform axial depth
• secondary retention (walls are divergent facially)

Question 7

tooth colored restorations

Answer 7

1. composites
2. compomers
3. glass ionomers
4. resin modified glass ionomers

Question 8

ideal class 5 cavity design is _____ shape

Answer 8

trapezoidal/kidney

Question 9

external walls of class 5 cavity preps

Answer 9

1. gingival wall
2. incisal/occlusal wall
3. mesial wall
4. distal wall

Question 10

internal wall

Answer 10

axial wall

Question 11

enamel rods have different ____ in different locations

Answer 11

directions

Question 12

directions of enamel rods:

Answer 12

horizontal, vertical, or oblique (diverge external)

Question 13

the distance of the external surface to the axial wall

Answer 13

axial depth

Question 14

____ thickness in the gingival 1/3 is not even and uniform

Answer 14

enamel

Question 15

clinically, the depth of ideal cavity preparation is _____

Answer 15

0.5 mm into dentin

Question 16

axial depth is ____ on the crown

Answer 16

1.0-1.25 mm

Question 17

axial depth is ____ on the root

Answer 17

0.75 mm

Question 18

preparation of the axial wall depth ___ into the DEJ results in a uniform depth for the entire preparation

Answer 18

0.5 mm

Question 19

Because the axial wall follows the mesiodistal and incisogingival contours of the facial surface of the tooth, it will usually be _____in both directions

Answer 19

convex

Question 20

incisal, gingival, mesial, and distal walls ____ to follow the enamel rods

Answer 20

diverge facially

Question 21

There is no _____ in ideal class V preparation

Answer 21

primary mechanical retention

Question 22

_____ is added like retention grooves

Answer 22

auxiliary/secondary