Deck 2: Oral Environment and Patient Considerations

Question 1

_____ force is applied when two surfaces slide against each other in opposite directions.

A) Compressive
B) Shearing
C) Tensile
D) Axial

Answer 1

Shearing

Question 2

Which of the following is considered to be the most reliable means of clinical assessment of composite and glass ionomer restorations?

A) The patient history
B) Evaluation of radiographs
C) Use of the air-water syringe
D) Tactile evaluation of the tooth surface

Answer 2

Tactile evaluation of the tooth surface

Question 3

Which of the following statements is correct about fatigue failure?

A) It is not a factor for restorative dental materials.
B) It is not dependent on conditions in the oral cavity.
C) It occurs as the result of a large,single-force application.
D) It occurs as the result of microscopic flaws that grow over time.

Answer 3

It is not dependent on conditions in the oral cavity.

Question 4

Which of the following restorative materials has a coefficient of thermal expansion and thermal conductivity closest to enamel?

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

Question 5

Which of the following dental restorative materials is particularly susceptible to corrosion?

A) Acrylic
B) Dental porcelain
C) Dental amalgam
D) Composite resin

Question 6

Normal masticatory forces on the occlusal surfaces of molar teeth can increase to as much as _____ pounds per square inch on a cusp tip.

A) 280
B) 1000
C) 10,000
D) 28,000

Question 7

What is percolation?

A) The rate at which heat flows through a material
B) A form of chemical rather than mechanical retention
C) Something that helps seal the interface between tooth and restorative material
D) Something that allows the ingress of bacteria and oral fluids and may lead to recurrent caries,staining,and pulpal irritation

Question 8

Which of the following has been suggested to delay formation of surface tarnish on dental amalgams?

A) Incremental addition
B) Polishing
C) Use of non-copper-containing dental amalgam
D) Undercondensation

Question 9

What could excessive expansion of a restorative material result in?

A) Corrosion
B) Galvanism
C) Fracture of cusps
D) Leakage of fluid and bacteria into the gaps

Question 10

Which of the following statements is true for the property of wetting as related to dental materials?

A) The Teflon surface of cooking equipment has good wetting.
B) A thin film of dental cement is desirable to cement crowns.
C) Liquids generally spread better over low surface energy surfaces.
D) A surface has high surface energy when liquids bead up on the surface.

Question 11

Which of the following is true of galvanism?

A) It is an electrical current transmitted between two similar metals.
B) It is observed in patients with composite resin but not silver amalgam restorations.
C) Galvanic stimulation will decrease with time as oxides form on the surface of the metal.
D) The salts of the saliva inhibit the movement of electrical current from one type of metal to another.

Question 12

The normal resting pH of saliva ranges from 6.2 to _____,which is neutral.

A) 1
B) 6.6
C) 7
D) 14

Question 13

Stress is the amount of force exerted from within an object,and _____ is the amount of change that the force has produced.

A) strain
B) tension
C) compression
D) chemical bonding

Question 14

Microleakage into the interface between tooth structure and restorative material is responsible for much of the _____ observed following tooth restoration.
1)recurrent decay
2)marginal staining
3)postoperative sensitivity
4)tarnish

A) 1,2,3,4
B) 1,2,3
C) 2,3,4
D) 1,2

Question 15

The staining of resins and acrylics from repeated exposure to coffee,tea,and other dyed beverages is due to:

A) compressive forces.
B) water sorption.
C) galvanism.
D) tarnish.

Question 16

Which of the following is the best thermal conductor?

A) Gold
B) Dentin
C) Enamel
D) Ceramic

Question 17

The technique of chemical bonding rather than mechanical means to produce retention requires _____ removal of tooth structure and produces a _____ retentive force between tooth and restoration.

A) more;stronger
B) more;weaker
C) less;stronger
D) less;weaker

Question 18

Some dental materials may be therapeutic in small quantities or if in contact with tissues for a short period of time.Dental materials may be irritating or toxic with longer or larger doses.

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

Question 19

_____ refers to the intensity or strength of the color.

A) Hue
B) Value
C) Chroma
D) Opacity

Question 20

Which of the following materials has the highest ultimate compressive strength (lbs/in²)?

A) Acrylic
B) Porcelain
C) Amalgam
D) Composite resins

Question 21

Match the items with the correct description below.
Tarnish

A)Electrical current between two dissimilar metals
B)Discoloration due to oxidation of the metal's surface
C)Deterioration of the metal due to moisture and acid present in the oral
D)The rate at which heat flows through a material
E)Opening and closing of a gap between the restoration and the tooth surface

Question 22

Match the items with the correct description below.
Thermal conductivity

A)Electrical current between two dissimilar metals
B)Discoloration due to oxidation of the metal's surface
C)Deterioration of the metal due to moisture and acid present in the oral
D)The rate at which heat flows through a material
E)Opening and closing of a gap between the restoration and the tooth surface

Question 23

What causes microleakage?

A) A poorly placed restoration
B) A fracture within a restoration
C) Expansion and contraction of a restoration
D) All of the above could cause microleakage.

Question 24

Contact between two dissimilar metals in the mouth may result in what reaction?

A) Galvanic shock
B) Metallic taste
C) Electrical current
D) All of the above are possible.

Question 25

Most modern dental materials are made to be moisture resistant.

Question 26

Of the three types of forces,which is most concerned with the stretching of a material?

A) Tensile force
B) Compressive force
C) Shearing force

Question 27

Which of the following is not a good conductor of temperature?

A) Gold crown
B) Amalgam restoration
C) Composite resin restoration

Question 28

Why is the coefficient of thermal expansion significant in dental materials?

A) It measures the change in volume and length of a restoration.
B) It measures the amount of percolation of the restoration interface.
C) It measures the change in oral temperature related to foods ingested.
D) It measures the amount of stress and strain placed on the restoration.

Question 29

Which term describes the thicker or thinner a material is?

A) Density
B) Viscosity
C) Flowability
D) Thixotropic

Question 30

Torque is a combination of which forces?

A) Compressive and tensile
B) Compressive and torsion
C) Shearing and tensile
D) Shearing and compressive

Question 31

Which of the following would not be an adverse effect of a material?

A) Toxicity
B) Hyposensitivity
C) Hypersensitivity
D) Postoperative sensitivity

Question 32

Match the items with the correct description below.
Corrosion

A)Electrical current between two dissimilar metals
B)Discoloration due to oxidation of the metal's surface
C)Deterioration of the metal due to moisture and acid present in the oral
D)The rate at which heat flows through a material
E)Opening and closing of a gap between the restoration and the tooth surface

Question 33

What is the thermal conductivity of composite resin?

A) Similar to tooth structure
B) Lower than tooth structure
C) Similar to metal restorations
D) Does not conduct temperature

Question 34

Match the items with the correct description below.
Galvanism environment

A)Electrical current between two dissimilar metals
B)Discoloration due to oxidation of the metal's surface
C)Deterioration of the metal due to moisture and acid present in the oral
D)The rate at which heat flows through a material
E)Opening and closing of a gap between the restoration and the tooth surface

Question 35

The color range of a tooth is usually seen by the human eye as yellow or brown.What is this component classified as?

A) Hue
B) Value
C) Chroma

Question 36

Adhesion is the method of _____ retention.

A) chemical
B) mechanical
C) dual

Question 37

Some materials give off heat when mixed.What is this called?

A) Chemical reaction
B) Exothermic reaction
C) Thermal conductivity
D) Coefficient of thermal expansion

Question 38

Which of the following is not a concern regarding identification of dental materials in the mouth?

A) Therapeutic agents could erode some materials.
B) Scaling could damage the surfaces of some materials.
C) Both are concerns when materials are identified.

Question 39

Which material listed would show the lowest level of solubility?

A) Amalgam
B) Composite resin
C) Porcelain
D) Cement

Question 40

When an object cannot resist force,_____ occurs.

A) deformation
B) distortion
C) deformation and distortion

Question 41

List and describe the three basic types of force.

Question 42

List and describe the three components of color.

Question 43

Match the items with the correct description below.
Percolation

A)Electrical current between two dissimilar metals
B)Discoloration due to oxidation of the metal's surface
C)Deterioration of the metal due to moisture and acid present in the oral
D)The rate at which heat flows through a material
E)Opening and closing of a gap between the restoration and the tooth surface