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

Calcium hydroxide

Answer

Zinc oxide eugenol (ZOE)

Answer

Glass ionomer liner

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

The etchant was left on too long and demineralized the enamel excessively

Answer

The tooth needs re-etching because the surface is too dry

Answer

Contamination with saliva has occurred during etching

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

Do not release fluoride

Answer

Set exclusively by acid-base reaction with no light curing

Answer

Are contraindicated under composite restorations

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

All at once to reduce working time

Answer

Large increments to build viscosity rapidly

Answer

A warm environment to accelerate setting

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

10 seconds

Answer

30–60 seconds

Answer

90 seconds

Question 6

A liner is different from a base primarily in terms of:

Accepted Answer

Thickness — liners are thin coatings while bases are built up for bulk and support

Answer

Chemical composition — liners always contain fluoride while bases do not

Answer

Setting time — liners take longer to set than bases

Answer

Application method — liners require mixing while bases are single-component

Question 7

After sealant placement, the patient complains of a high bite on the sealed tooth. The EFDA should:

Accepted Answer

Adjust the occlusion with a finishing bur

Answer

Tell the patient it will wear down on its own

Answer

Remove the sealant and replace it

Answer

Apply additional sealant to even out the surface