EFDA Bases, Liners, and Sealants 4

Question 1

Which of the following bases has the highest compressive strength and is most suitable beneath a large amalgam restoration?

Accepted Answer

Zinc phosphate cement

Answer

Zinc phosphate cement has the highest compressive strength among traditional bases, providing adequate mechanical support under amalgam.

Question 2

An EFDA notices the sealant appears chalky white and opaque after rinsing the acid etchant. This appearance indicates:

Accepted Answer

Proper acid etching has created the correct micro-porous enamel surface

Answer

A chalky, frosted white appearance after rinsing is the expected sign that phosphoric acid has correctly etched the enamel surface for bonding.

Question 3

Resin-modified glass ionomer (RMGI) liners differ from conventional glass ionomer liners primarily in that they:

Accepted Answer

Contain resin components allowing light-cured, faster initial set

Answer

RMGI contains resin monomers that allow light-cured polymerization for immediate command set, while also undergoing the glass ionomer acid-base reaction.

Question 4

When mixing zinc phosphate cement for a base, the powder is incorporated into the liquid in:

Accepted Answer

Small increments over a large, cool glass slab to dissipate heat

Answer

Small powder increments are added gradually to the liquid on a cool glass slab to control the exothermic setting reaction and extend working time.

Question 5

Which of the following is the correct etch time for permanent enamel when applying a pit and fissure sealant?

Accepted Answer

15–20 seconds

Answer

Current clinical guidelines recommend etching permanent enamel for 15–20 seconds to achieve adequate micro-mechanical retention without over-etching.

(EFDA) Expanded Function Dental Auxiliary Practice Test

(EFDA) Expanded Function Dental Auxiliary Practice Test

EFDA Bases, Liners, and Sealants 4