Lab 3: Class I Amalgam Restoration

Question 1

outline form of Class I amalgam restoration

Answer 1

smooth, flowing, gentle curves

Question 2

rationale for outline form in Class I am. restorations

Answer 2

• angular contours can chip and lead to fracture

- easier to find when carving back fresh amalgam

Question 3

angular irregularity that where tissue goes into itself; susceptible to fracture during condensation

Answer 3

invagination

Question 4

angular irregularity where tissue extends outward from itself; is difficult to condense into

Answer 4

evagination

Question 5

a balance between conservation of tooth structure and need for access and to remove defective tooth structure

Answer 5

extension

Question 6

extend triangular ridges _____

Answer 6

minimally

Question 7

isthmus is ideally ____ of the intercuspal distance

Answer 7

less than 1/3

Question 8

in clinic, ____mm into dentin is the right depth

Answer 8

0.5

Question 9

Bu and Li walls convergent in _____ ____

Answer 9

triangular ridges

Question 10

Bu and Li walls divergent in _____ _____

Answer 10

groove extensions

Question 11

degree of convergence/divergence

Answer 11

6 degrees

Question 12

mesial and distal walls ____ by _ degrees

Answer 12

divergent, 6

Question 13

sharp angles are ___ ____

Answer 13

stress initiators

Question 14

rounded fissure burs such as the ____ will create a well-defined but not ___ line angle

Answer 14

245, sharp

Question 15

3 extensions

Answer 15

Bu-Li
M-D
Occlusal depth (depth to pulpal floor)

Question 16

when extending M-D, you need to stop ___ of the marginal ridges

Answer 16

short