EFDA Impression Materials and Techniques 2

Question 1

Which impression material is most appropriate for capturing a final impression for a complete denture?

Accepted Answer

Zinc oxide eugenol (ZOE) paste

Answer

Zinc oxide eugenol paste is a mucostatic material commonly used for final complete denture impressions because it records tissues in a resting state.

Question 2

What is the primary reason polyether impression materials require careful storage conditions?

Accepted Answer

They absorb water and dimensional changes occur in humid environments

Answer

Polyether materials are hydrophilic and can absorb moisture from the air or storage environment, causing dimensional inaccuracies.

Question 3

When mixing addition silicone (PVS) impression material, what should the clinician avoid?

Accepted Answer

Using latex gloves during mixing

Answer

Sulfur compounds in latex gloves can inhibit the polymerization of addition silicone, resulting in a tacky, unset surface.

Question 4

A 'monophase' impression technique using PVS means:

Accepted Answer

The same viscosity material is used in both the syringe and tray simultaneously

Answer

In the monophase technique, a medium-viscosity PVS is loaded in both the syringe and the tray and placed simultaneously.

Question 5

Which property of addition silicone makes it preferred for implant-level impressions?

Accepted Answer

Excellent dimensional stability allowing delayed pours

Answer

PVS impressions can be stored for days to weeks without significant dimensional change, making them ideal when models must be poured remotely or later.

(EFDA) Expanded Function Dental Auxiliary Practice Test

(EFDA) Expanded Function Dental Auxiliary Practice Test

EFDA Impression Materials and Techniques 2