complex amalgam restorations

Question 1

when to replace a cusp

Answer 1

when the facial or lingual extension exceeds 2/3 the distance from a primary groove towards the cusp tip
when the facial-lingual extension of the occlusal preparation exceeds 2/3 the distance between facial-lingual cusps
when the cusp is not well supported by dentin

Question 2

types of pins

Answer 2

cemented
friction locked
threaded

Question 3

type of pin used in class

Answer 3

threaded (.024/.61)-silver

Question 4

where is the whole for a pin placed

Answer 4

2 drill diameters from the DEJ along the line angles

at angle that matches that of the external surface of the tooth (parallel to the root surface)

Question 5

2222 rule

Answer 5

2mm pin hole depth
2mm drill diamter inside the DEJ
2mm length of pin
2mm amalgam over pin

Question 6

location of retentive wells

Answer 6

1/2mm into the DEJ with an undercut

need to be able to fit the small condensor

Question 7

drill diamter

pin diameter

Answer 7

.53 mm

.61mm