Cario: Cavity Design: Class I

Question 1

Describe the stages of caries progression on an occlusal pit/fissure surface: (Which stage should we start drilling teeth for filling?)

Answer 1

Filling should take place on critical event (when enamel is broken down)

Question 2

Before we prepare a class I filling, what 2 things should we do?

Answer 2

1. Use articulating paper to find occlusal contact- prevents us from drilling a margin where teeth bites.
2. Handpiece is parallel tooth’s crown before prep- this ensures we don’t remove too much teeth.

Question 3

What is the correct way we must position our handpiece when preparing a class I filling? (which teeth has an exception)

Answer 3

Question 4

What are the two types of filling material that we can use for class I filling?

Answer 4

Question 5

Give a step by step summary of a class I preparation

Answer 5

Question 6

Describe or sketch the outline form of moderate to large Class I cavities for composite resin filling material:

Answer 6

outline form:
area of the tooth surface to be included in the prepared cavity
overall outline of the preparation determined by peripheral walls

Factors affecting outline form:
* surface anatomy
* extent of caries
* retention and resistance
* convenience form

Question 7

What does resistance form mean and how do we ensure it when preparing a class I filling?

Answer 7

Natural design upon caries removal - sufficient
* depth of the cavity (depth 1.5-2 mm at M/D end)
* thickness of remaining cavity walls
* internal angles
* pulpal wall (floor) - flat
* cavosurface angle
No additional specific features required

Question 8

What does retention form mean and how do we ensure it when preparing a class I filling?

Answer 8

Question 9

What does convenience form mean and how do we ensure it when preparing a class I filling?

Answer 9

Question 10

After initial preparation-if there is still decay. How should we remove the remaining decay?

Answer 10

Question 11

What is expected of our External wall finishing when preparing class I cavities?

Answer 11

• smooth, angles slightly rounded (curved), no sharp angles this will reduce stress on teeth)
• removal of extremely friable (undermined) enamel
• external surface and adjacent cavity surface (cavosurface angle) ~ 90°
• no bevel required in Class I for CRs

Question 12

During Cavity debridement what must you consider?

Answer 12

Question 12

During Cavity debridement what must you consider?

Answer 12