NBDHE Dental Materials and Procedures Questions and Answers

Question 1

A dental hygienist prepares an alginate impression for a study model.
Upon inspection, the final impression has a grainy, rough surface and lacks fine detail.
Which of the following is the MOST likely cause of this error?

Accepted Answer

Inadequate spatulation of the powder and liquid

Answer

Using water that was too cold

Answer

Leaving the impression in the patient's mouth for too long

Answer

Over-spatulation of the material

Question 2

Which of the following is a primary advantage of using a microfilled composite resin for a Class V restoration on a maxillary canine?

Accepted Answer

High polishability resulting in excellent esthetics

Answer

Superior fracture toughness compared to hybrid composites

Answer

Low coefficient of thermal expansion

Answer

High filler content providing superior strength

Question 3

A patient requires a temporary crown on a tooth that is sensitive and diagnosed with reversible pulpitis. The dentist needs a luting cement that will have a palliative, or soothing, effect on the pulp. Which cement is the BEST choice?

Accepted Answer

Zinc Oxide Eugenol (ZOE) cement

Answer

Glass ionomer cement

Answer

Resin-modified glass ionomer cement

Answer

Zinc phosphate cement

Question 4

The long-term retention of a pit and fissure sealant is MOST dependent on which of the following steps during its application?

Accepted Answer

Meticulous isolation to maintain a dry field

Answer

Using air-powder polishing to prepare the enamel surface

Answer

Applying a fluoride varnish immediately prior to etching

Answer

Curing the sealant material for a minimum of 60 seconds

Question 5

A dental hygienist is performing coronal polishing on a patient with generalized enamel and a few composite restorations. To minimize abrasion and preserve the integrity of these surfaces, the polishing agent selected should have which characteristics?

Accepted Answer

Low hardness and small, round particle size

Answer

High hardness and large, irregularly shaped particles

Answer

Low speed of application and high pressure

Answer

A coarse grit and a dry application technique

Question 6

A patient is undergoing an in-office vital tooth whitening procedure. The material applied to the teeth is a high-concentration gel that works by oxidizing stain molecules. What is the primary active ingredient in MOST in-office tooth whitening systems?

Accepted Answer

Hydrogen peroxide

Answer

Sodium perborate

Answer

Carbamide peroxide

Answer

Sodium hypochlorite