NBDHE Dental Materials and Procedures 3

Question 1

What is the primary advantage of resin-modified glass ionomer (RMGI) over conventional glass ionomer cement?

Accepted Answer

Improved physical properties and command set via light curing while retaining fluoride release

Answer

Complete elimination of water sensitivity

Answer

Greater compressive strength than amalgam

Answer

No chemical adhesion to tooth structure

Question 2

Zinc phosphate cement is best characterized as:

Accepted Answer

A cement with high compressive strength and low tensile strength, requiring pulpal protection due to initial acidity

Answer

A biocompatible, fluoride-releasing material used as a permanent restorative

Answer

An elastomeric luting agent with flexible set

Answer

A calcium hydroxide-based direct pulp capping material

Question 3

Which instrument is used to condense amalgam into a prepared cavity?

Accepted Answer

Amalgam condenser (plugger)

Answer

Burnisher

Answer

Carver

Answer

Matrix band

Question 4

The color stability of composite resins is primarily affected by which process over time?

Accepted Answer

Oxidative discoloration of resin matrix and water sorption

Answer

Fluoride release causing surface staining

Answer

Calcium loss from the inorganic filler

Answer

Thermal contraction of the restoration

Question 5

When taking an elastomeric impression, the tray adhesive should be applied:

Accepted Answer

At least 15 minutes before taking the impression to allow it to dry completely

Answer

Immediately before loading the tray with impression material

Answer

After placing the impression material in the tray

Answer

Only for hydrophilic impression materials

Question 6

What is the function of eugenol in zinc oxide eugenol (ZOE) impression paste and temporary cements?

Accepted Answer

It acts as the liquid component that reacts with zinc oxide to form a chelate, providing obtundent (sedative) effects

Answer

It provides rigidity after setting

Answer

It releases fluoride for caries prevention

Answer

It acts as the plasticizer to improve flexibility