EFDA Provisional Crown Fabrication 4

Question 1

When fabricating a provisional for a patient with known acrylic monomer sensitivity, the BEST alternative material is:

Accepted Answer

Bis-acryl composite resin

Answer

PMMA with increased powder-to-liquid ratio

Answer

Polyether impression material

Answer

Zinc oxide eugenol paste

Question 2

The purpose of applying petroleum jelly (Vaseline) to the tooth and adjacent tissues before injecting provisional material is to:

Accepted Answer

Act as a separating medium to prevent adhesion to tissues and teeth

Answer

Improve the bond between provisional material and tooth

Answer

Disinfect the preparation before temporization

Answer

Reduce sensitivity of the prepared dentin

Question 3

Which of the following is a sign of inadequate curing of a PMMA provisional crown?

Accepted Answer

Tacky or soft surface and persistent monomer odor

Answer

Excessive hardness and brittleness

Answer

Bright white opaque color

Answer

Excessive shrinkage at the margins

Question 4

A provisional crown is fractured at the isthmus connecting two pontics in a three-unit fixed partial denture. The MOST likely cause is:

Accepted Answer

Insufficient bulk of material at the connector area

Answer

Excess temporary cement

Answer

Overly aggressive polishing

Answer

Using too much separating medium

Question 5

When seating a provisional crown, the patient should be instructed to bite on a cotton roll to:

Accepted Answer

Help fully seat the crown and verify occlusal fit

Answer

Absorb excess cement

Answer

Prevent the patient from biting the tongue

Answer

Reduce postoperative sensitivity

Question 6

The color shade of a provisional crown is MOST important for which type of restoration?

Accepted Answer

Maxillary central incisor

Answer

Mandibular second molar

Answer

Mandibular first premolar

Answer

Maxillary third molar

Question 7

Which type of bur is BEST suited for adjusting internal fit of a bis-acryl provisional crown?

Accepted Answer

Round carbide bur at low speed

Answer

Diamond bur at high speed

Answer

Sandpaper disc

Answer

12-fluted finishing bur