Bases, Liners, and Sealants Flashcards

Which liner material releases fluoride ions to help prevent secondary caries beneath a restoration?

Answer: Glass ionomer liner

Glass ionomer liners release fluoride, which provides ongoing anticaries protection at the tooth-restoration interface.

What is the primary purpose of placing a base under a deep amalgam restoration?

Answer: To provide thermal insulation and pulpal protection

A base provides thermal insulation to protect the pulp from temperature changes conducted through the metal restoration.

A pit and fissure sealant is indicated when the fissure morphology is:

Answer: Deep and narrow, retaining plaque and debris

Deep, narrow pits and fissures that cannot be cleaned by toothbrushing are the primary indication for sealant placement.

Which material is contraindicated as a liner directly over a pulp exposure because of its low pH?

Answer: Zinc phosphate cement

Zinc phosphate cement has a very low initial pH (around 3.5) that can cause pulpal irritation and is contraindicated near direct pulp exposures.

When applying a resin sealant, moisture contamination before light curing will most likely cause:

Answer: Poor adhesion and early sealant loss

Moisture contamination disrupts the bond between the etched enamel and the resin sealant, leading to microleakage and early failure.

Dentin bonding agents used under composite restorations serve primarily to:

Answer: Seal the smear layer and bond resin to tooth structure

Dentin bonding agents penetrate and seal the smear layer while creating a hybrid layer that bonds resin composite to dentin.

Which of the following is a characteristic of zinc oxide eugenol (ZOE) as a temporary base?

Answer: Sedative effect on the pulp due to eugenol

Eugenol has a sedative, obtundent effect on pulpal tissue, making ZOE useful under painful or sensitive restorations.