Review of Class I cavity prep for amalgam and grading criteria_ Dr. Shah lecture

Question 1

when caries or other defects occur on the occlusal surface of posterior teeth

Answer 1

classification of class I caries

Question 2

no chemical bonding for __restoration

Answer 2

amalgam

Question 3

removal of caries and defects, extension of the margins on the sound enamel, preservation of sound tooth structure

Answer 3

outline form

Question 4

minimizes fracture potential of the tooth and restoration, that means we need adequate thickness of the amalgam restoration to withstand the occlusal forces

Answer 4

resistance form

Question 5

depth for amalgam

Answer 5

1.75mm

Question 6

isthmus width

Answer 6

1.0-1.25mm

Question 7

what form? cavity prep should have adequate retention features to prevent __, right angulation of walls and flat pulpal floor

Answer 7

dislodgment of the restoration

retention form

Question 8

cavity prep should be large enough to permit visualization and proper instrumentation

Answer 8

convenience form

Question 9

common errors of prep

Answer 9

over/under extension

incorrect angulation of buccal and lingual walls

M and D walls too much diverging

floor too deep/shallow

rough/sharp cavosurface margin

Question 10

ideal buccal and lingual walls

Answer 10

convergent occlusally

Question 11

what is the problem with over convergent buccal/lingual walls

Answer 11

chances of poorly condense amalgam near the axiopulpal line angle

Question 12

ideal proximal walls (M and D)

whats ideal angulation?

Answer 12

slightly divergent to follow enamel rods

6-8 degrees

Question 13

problem with too shallow of a pulpal depth

Answer 13

inadequate thinkness affects resistance form

Question 14

problem with too deep pulpal floor

Answer 14

unnecessary removal of healthy dentin and increased chance of approaching pulp horns or even pulp exposure

Question 15

problem with sharp line angles

Answer 15

sharp areas lead to concentration of the applied stress