39. Secondary phases of cavity preparation, definition of each phases.

Question 1

Secondary phase of cavity preparation
1. What are the 5 main steps in secondary phase?

Answer 1

1/ removal of infected dentin and old filling
2/ pulp protection
3/ secondary resistance and retention form
4/ finishing the prepared walls
5/ cleaning, inspecting

Question 2

Secondary phase of cavity preparation
2. Why do we need to remove infected dentin and old restorations?

Answer 2

1/ infected dentin always has to be removed

2/ old restoration should be removed, if:
- negatively affect the new one
- compromise in retention
- caries is under the filling
- the pulp was sympthomatic preoperatively
- the periphery of remaining filling is not intact

Question 3

Secondary phase of cavity preparation
3. How do we protect the pulp?

Answer 3

Preparation can cause thermal irritation
=> It needs watercooling

Question 4

Secondary phase of cavity preparation
4. what is the aim of step 4 “finishing the prepared walls”?

Answer 4

aim of finishing is to create the best marginal seal between the the restorative material and tooth;
smooth marginal junction; provide maximum strength of both the tooth and filling near the margin