Deck 3: Physical Properties of Dental Materials

Question 1

If the molecules of a solid are arranged in a random form with no regular pattern, the solid is called:

A) thixotropic
B) amorphous
C) malleable
D) ductile

Answer 1

amorphous

Question 2

The maximum amount of stress a material can take before breaking is known as its:

A) ultimate capacity
B) maximum elasticity
C) ultimate strength
D) material hardness

Answer 2

ultimate strength

Question 3

Which of the following is the hardest material?

A) Cementum of a tooth
B) Enamel of a tooth
C) Composite resin restorative material
D) Cast gold restorative material

Answer 3

Enamel of a tooth

Question 4

Which of the following is an example of a direct restorative material?

A) Porcelain inlay
B) Cast gold crown
C) Silver dental amalgam restoration
D) Ceramic implant abutment

Question 5

Of the following, which is not an application of a material's classification?

A) Its longevity
B) Its utilization
C) Its fabrication
D) All of these are correct.

Question 6

Metals that can withstand dimensional change without breaking are:

A) resilient
B) tough
C) malleable
D) ductile

Question 7

A _______ material will flow more easily under mechanical pressure.

A) viscous
B) thixotropic
C) resistance
D) therapeutic

Question 8

Which type of bond occurs when two atoms share electrons in their outer shell, creating full shells for both?

A) Ionic bond
B) Covalent bond
C) Metallic bond
D) Hydrogen bond

Question 9

Which of the following statements is true concerning desirable properties of dental materials?

A) The maximum amount of stress a material can withstand without breaking is known as the proportional limit.
B) Stiffer materials have a high modulus of elasticity.
C) Resilience is the ability of a material to resist fracture.
D) In most cases, metals tend to be brittle and ceramics tend to be ductile and malleable.

Question 10

Dental plaster begins with ________________ components.

A) water and powder
B) liquid and powder
C) paste and liquid
D) paste and paste

Question 11

In general, ________ temperature and ________ humidity will accelerate the reaction of the material.

A) high; high
B) high; low
C) low; high
D) low; low

Question 12

______________ is the time permitted to manipulate the material in the mouth.

A) Mixing time
B) Working time
C) Initial set time
D) Final set time

Question 13

Which of the following is true concerning initial and final setting times?

A) The material must not be disturbed through the end of the final set.
B) Moisture and pressure controls are frequently important during the initial set.
C) The final set always occurs while the patient is still in the dental office.
D) Once a material has reached the initial set, it will not fracture.

Question 14

Which of the following are considered to be therapeutic dental materials?

A) Fluorides and pit and fissure sealants
B) Medicated bases or topical treatments for periodontal disease
C) Filling, inlay, crown, bridge, or implant
D) Partial or complete denture

Question 15

The stability of a solid is evaluated by noting:

A) how hard the material is when set
B) whether or not it is a compound
C) whether the molecules are arranged uniformly
D) its atomic mass and number

Question 16

Which of the following is not a primary bond?

A) Hydrogen
B) Covalent
C) Ionic
D) Metallic

Question 17

Dual set materials utilize _______________ setting reactions.

A) both light-activated and chemical
B) light-activated but not chemical
C) chemical setting but not light-activated
D) neither light-activated nor chemical

Question 18

Liquids are evaluated by their:

A) viscosity
B) flowability
C) wettability
D) resistance

Question 19

The higher the viscosity, the greater is a liquid's ability to resist flow. Usually, the viscosity of liquids increases as the temperature increases.

A) Both statements are true.
B) Both statements are false.
C) The first statement is true, the second statement is false.
D) The first statement is false, the second statement is true.

Question 20

Which of the following is an example of a secondary rather than primary bond?

A) Metallic bond
B) Van der Waals bond
C) Covalent bond
D) Ionic bond

Question 21

Match the items with the correct description below.
Toughness

A)Resistance to deformation
B)The greatest stress a structure can withstand without permanent
C)The resistance of a solid to penetration
D)The maximum amount of stress a material can withstand without
E)The ability of a material to resist fracture

Question 22

Altering the set ratios of a material for any purpose will:

A) make the material harder
B) produce adverse results
C) speed up the initial set
D) have little significance

Question 23

Match the items with the correct description below.
Stiffness

A)Resistance to deformation
B)The greatest stress a structure can withstand without permanent
C)The resistance of a solid to penetration
D)The maximum amount of stress a material can withstand without
E)The ability of a material to resist fracture

Question 24

The use of expired or improperly stored materials may:

A) render the material ineffective
B) cause a toxic reaction
C) be of little consequence

Question 25

Match the items with the correct description below.
Ultimate strength deformation

A)Resistance to deformation
B)The greatest stress a structure can withstand without permanent
C)The resistance of a solid to penetration
D)The maximum amount of stress a material can withstand without
E)The ability of a material to resist fracture

Question 26

Match the items with the correct description below.
Hardness

A)Resistance to deformation
B)The greatest stress a structure can withstand without permanent
C)The resistance of a solid to penetration
D)The maximum amount of stress a material can withstand without
E)The ability of a material to resist fracture

Question 27

The reaction initiated when a catalyst and a base are mixed together will be:

A) chemical
B) physical
C) dual
D) All are possible reactions.

Question 28

List and describe the three types of primary bonds.

Question 29

List and describe the three different classifications of dental materials.

Question 30

Match the items with the correct description below.
Initial set time homogenous mix

A)Begins when the material can no longer be manipulated in the mouth
B)When the material has reached its ultimate state
C)The amount of time the auxiliary has to bring the components together into a
D)The time permitted to manipulate the material within the mouth

Question 31

Match the items with the correct description below.
Final set time

A)Begins when the material can no longer be manipulated in the mouth
B)When the material has reached its ultimate state
C)The amount of time the auxiliary has to bring the components together into a
D)The time permitted to manipulate the material within the mouth

Question 32

Which of the following would not be considered a direct placement restorative material?

A) Gold
B) Gold foil
C) Amalgam
D) Composite resin

Question 33

Match the items with the correct description below.
Proportional limit breaking

A)Resistance to deformation
B)The greatest stress a structure can withstand without permanent
C)The resistance of a solid to penetration
D)The maximum amount of stress a material can withstand without
E)The ability of a material to resist fracture

Question 34

Match the items with the correct description below.
Working time

A)Begins when the material can no longer be manipulated in the mouth
B)When the material has reached its ultimate state
C)The amount of time the auxiliary has to bring the components together into a
D)The time permitted to manipulate the material within the mouth

Question 35

Match the items with the correct description below.
Mixing time

A)Begins when the material can no longer be manipulated in the mouth
B)When the material has reached its ultimate state
C)The amount of time the auxiliary has to bring the components together into a
D)The time permitted to manipulate the material within the mouth