Verified Practice Examination
Original Questions with Detailed
Rationales.
Question 1
What are the three main classifications of dental materials?
A) Biological, Chemical, Physical
B) Preventive, Restorative, Auxiliary/Therapeutic
C) Organic, Inorganic, Metallic
D) Hard, Soft, Semi-rigid
Correct Answer:-B
Rationale: Dental materials are broadly classified into preventive (fluoride,
sealants), restorative (amalgam, composite, gold),
and auxiliary/therapeutic (cements, liners, impression materials). The biological,
chemical, and physical properties are aspects of materials, not classifications.
Organic/inorganic/metallic refers to the chemical composition.
Question 2
Which of the following is considered a preventive dental material?
A) Amalgam
B) Fluoride varnish
C) Composite resin
D) Dental cement
Correct Answer:-B
Rationale: Fluoride varnish is a preventive dental material used to prevent dental
caries. Amalgam and composite resin are restorative materials. Dental cement is an
auxiliary material used for cementation or as a base/liner.
,Question 3
Which of the following is a restorative dental material?
A) Composite resin
B) Fluoride varnish
C) Dental stone
D) Impression material
Correct Answer:-A
Rationale: Composite resin is a restorative material used to restore tooth structure
that has been lost due to decay or trauma. Fluoride varnish is preventive. Dental
stone is a laboratory material. Impression materials are used for making replicas of
oral structures.
Question 4
Which of the following is an auxiliary/therapeutic dental material?
A) Amalgam
B) Zinc oxide eugenol (ZOE) cement
C) Composite resin
D) Ceramic
Correct Answer:-B
Rationale: Zinc oxide eugenol (ZOE) cement is an auxiliary/therapeutic material
used as a temporary cement, base, or sedative dressing. It is not a permanent
restorative material. Amalgam, composite resin, and ceramics are restorative
materials.
Question 5
The primary requirement for any dental material used in the oral cavity is:
A) Aesthetic appearance
B) Biocompatibility and safety
C) Low cost
D) Ease of manipulation
,Correct Answer:-B
Rationale: The primary requirement for any dental material used in the oral cavity
is biocompatibility and safety—the material must not be toxic, irritant, or harmful
to the oral tissues. While aesthetics, cost, and ease of manipulation are important,
safety is paramount.
Question 6
A material's ability to withstand stress without permanent deformation is known as:
A) Hardness
B) Strength
C) Toughness
D) Elasticity
Correct Answer:-B
Rationale: Strength is the ability of a material to withstand stress without
permanent deformation or fracture. Hardness is resistance to indentation.
Toughness is resistance to fracture. Elasticity is the ability to return to original
shape after stress is removed.
Question 7
The term "viscosity" describes a material's:
A) Resistance to flow
B) Ability to conduct heat
C) Color stability
D) Hardness
Correct Answer:-A
Rationale: Viscosity is a measure of a material's resistance to flow. High
viscosity materials are thick and flow slowly (e.g., heavy-body impression
material); low viscosity materials flow easily (e.g., light-body impression
material). Viscosity affects material handling and adaptation.
, Question 8
The ability of a material to be stretched or elongated without breaking is called:
A) Hardness
B) Ductility
C) Brittleness
D) Compressive strength
Correct Answer:-B
Rationale: Ductility is the ability of a material to be stretched or elongated
without breaking. Gold is highly ductile. Malleability is the ability to be hammered
or rolled into thin sheets. Brittleness is the tendency to fracture without
deformation.
Question 9
The property of a material that allows it to return to its original shape after
deformation is called:
A) Elasticity
B) Plasticity
C) Hardness
D) Toughness
Correct Answer:-A
Rationale: Elasticity is the property of a material that allows it to return to its
original shape after deformation when the stress is removed. Plasticity is the ability
to undergo permanent deformation without fracture.
Question 10
Which of the following is a measure of a material's ability to resist indentation?
A) Hardness
B) Strength
C) Toughness
D) Elasticity
Correct Answer:-A