Question

After trying the provisional crown on the prepared tooth, you notice the margins are too short. What is your plan of action in adjusting the provisional so that it will fit properly?

Answer 1

Answer:

In general, a crown with short margins or an insufficient margin should be reconstructed entry and be remade with a special margin ceramics.

If one wish to transfer the insufficiency or the lack to the dental technician for to be adapted, the following approach may come in handy;

1. The margin of the crown should be cut back in the area of the gap 1.0 mm superior/before the margin of the preparation. Make sure that there is a pronounced bevel.

2. An impression should be taken on a (e.g. polyether) with the positioned crown as needed.

3. Cast the impression with a special resin.

Explanation:

The preparation process involves the shrinkage of the ceramics at the firing process stage, the marginal fit should be tolerable at best.

Limitation of strength of the veneering ceramic special margin (approx. 80 MPa) should be tested before implementation.