Dental Materials Test 1

Question 0

Amount of force applied to a specific area

Answer 0

Stress=force/area

Question 1

What base is still used: stimulate dentin formation and ph raises as it dissolves

Answer 1

calcium hydroxide

Question 2

Internal rearrangement of atoms to adjust to the stress-deformation results

Answer 2

Strain=deformation/length

Question 3

Forces on object directed away from each other - stretched or elongated…ability of an object to resist pulling

Answer 3

Tensile

Question 4

Resistance in the material to the external force - ability to resist pushing

Answer 4

Compressive

Question 5

Ability to resist tearing - forces directed parallel to each other. Occurs when one portion of a structure is forced to slide by another portion (i.e.. scissors)

Answer 5

Shear

Question 6

Stiffness of material, maximum stress w/o permanent deformation. Material can’t regain its size and/or shape

Answer 6

Elastic limit - proportional limit

Question 7

Point just before fracture

Answer 7

Ultimate strength

Question 8

Ability of material to be drawn into a wire

Answer 8

Ductility = elongation

Low ductility = brittleness

Question 9

Ability to be hammered or rolled into thin sheets without fracture- compression

Answer 9

Malleability

Question 10

Energy necessary to cause permanent deformation

Answer 10

Resilience

Question 11

Ability of material to resist fracture

Answer 11

Toughness

Question 12

Gradual permanent change in dimension that occurs in an object due to constant loading
Flow after set (amalgam)

Answer 12

Creep

Question 13

Resistance of material to flow

Answer 13

Viscosity

Question 14

Some materials have a high viscosity but change w/pressure (mixing)…impression materials change thru manipulation

Answer 14

Thixotropic

Question 15

Depth of an indentation made with a steel ball- composites ↕️

Answer 15

Rockwell (RHN) hardness

Question 16

Measuring the length of a diagonal made with a diamond indenter- metals and porcelain ↔️

Answer 16

Knoop (KHN) hardness

Question 17

The repeated application of stress to an object causing tiny cracks to be generated within the structure until failure occurs

Answer 17

Fatigue

Question 18

Pt ed. for 12 year old who is going to play field hockey….

Answer 18

Mouthguard

Question 19

How do cements look on an X-ray?

Answer 19

Opaque

Question 20

Dental cement can be used as a base…

• Can it protect pulp?
• Adequate compressive strength?
• Is it a poor conductor of temp

Answer 20

Yes all of above

Question 21

Most conservative tx for 43 yr old with extensive internal stains- finances not an issue

Answer 21

Veneers

Question 22

New material should have hardened when light passed, but didn’t… you would say material did not what?

Answer 22

Cure

Question 23

Which type of composite has the lowest viscosity

Answer 23

Flowable

Question 24

Filler size and polishability, easier to polish what?

Answer 24

Microfilled

Question 25

What releases Fluoride?

Answer 25

Glass ionomer

Question 26

What function does kaolin perform in porcelain

Answer 26

Causes parameters to be cohesive when wet and it adds pigment

Question 27

Bases help to do what with thermal conductivity?

Answer 27

Limit/eliminate

Question 28

What do varnishes do?

Answer 28

Seal dentin tubules

Question 29

What is the best base to use in a deep cavity prep

Answer 29

calcium hydroxide

Question 30

Don’t use ZOE under a material that you want to what? (i.e. composite)

Answer 30

polymerize

Question 31

Copalite is to what?

Answer 31

Seal dentinal tubules

Question 32

What is created with high speed, debris of enamel and dentin

Answer 32

Smear layer

Question 33

Pt with history of sensitive teeth, requires amalgam restoration of max molar which base material may be the best choice

Answer 33

glass ionomer

Question 34

Base metal alloys are utilized to make what?

Answer 34

Crowns, bridges, PFM

Question 35

Can glass ionomers be utilized as cements and restorations and bases?

Answer 35

Yes

Question 36

Which are characteristics of glass ionomers?

Answer 36

release fluoride, bond to composite, enamel and dentin

Question 37

Which element is most responsible for reacting with mercury causing amalgam to set up?

Answer 37

Silver

Question 38

Pt. comes in with amalgam of equivalent age in 2 first molars, amalgam in #19 shows more marginal breakdown than the one in #30?

Answer 38

Both of these answers are correct - amalgam in 19 is less corrosion resistant than 30 - amalgam in tooth 19 has higher creep than 30

Question 39

Advantage of amalgam...

Answer 39

Easy to insert, manipulate, resists fracture

Question 40

Corrosion effects the Cavo surface margin

Answer 40

True..(where amalgam and tooth meets)

Question 41

What percent of gold is in 18 k gold?

Answer 41

75%

Question 42

Compared to pure gold, dental gold alloys are:

Answer 42

Harder

Question 43

Which type of porcelain is used in a porcelain fused to metal crown?

Answer 43

Low fusing (if it were high fusing it would melt the metal that has already been built on the prep. Tooth)

Question 44

As a metal restoration ages micro-leakage does what?

Answer 44

Decreases because of the process corrosion (self seals)

Question 45

Pt presents with well defined very red scalloped area along gingival margin, adjacent to base metal crown which of the following is not a cause... ​-sub gingival crown margin ​-nickel allergy ​-galvanic reaction

Answer 45

Galvanic reaction

Question 46

What restorations can be placed to provide healing time

Answer 46

ZOE

Question 47

How can mercury enter body?

Answer 47

Inhaling, ingestion, across skin

Question 48

Which setting phase of amalgam adds strength

Answer 48

gamma 1

Question 49

Which phase is most detrimental

Answer 49

gamma 2​

Question 50

Similar to a filling, but indirect, contained within cusps, cemented

Answer 50

Inlay

Question 51

Indirect restoration on the occlusal surface, includes a cusp, cemented or bonded

Answer 51

Onlay

Question 52

Considered color name

Answer 52

Hue

Question 53

Lightness or darkness of a color (hue)

Answer 53

Value

Question 54

Vividness or strength of a color or hue (difference between 1 or 2 coast of paint)

Answer 54

Chroma

Question 55

The way the light is affected when entering a substance

Answer 55

Translucency

Question 56

Components of porcelain

Answer 56

Combo of Kaolin, feldspar, and quartz...porcelain is fired whereas ceramic is machine milled.