Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AVDC Flash Cards > Craig's Restoration Fundamentals of Material > Flashcards

Craig's Restoration Fundamentals of Material Flashcards

1
Q

Define Biomechanics

A

Study of how biological material interact and deform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define Force

A

Generated when one body interacts with another (direct contact of distance (gravity))

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Translation or deformation occurs with..

a. Body Constrained
b. No Constrain on body

A

a. If body constrained, deformation/change of shape occurs
b. If no constrain on body, then translation or movement of body occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is the highest occlusal force?

A

Highest is in posterior ridge closet to the mandibular hinge axis

The force decreases as it moves mesially

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define stress

A

When forces acts on constrained body, the body resists the force.

Internal reaction is equal in magnitude and opposite in direction to applied by external force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the formula for stress?

A

Stress = Force per area (Force/area)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 2 basic types of Stress?

Sub types?

A
  1. Axial
    1. Tension
    2. Compression
  2. Shear
    1. Torsion
    2. Bending/Flexure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define Tension

A

2 sets of forces directed away from each other in the same straight line

or

One end is constrained and the other end is subjected to a force directed away constraint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define Compression

A

2 sets of forces directed towards each other in the same straight line

or

One surface is constrained and the other is subjected to a force directed toward the constraint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define shear

A

2 sets of forces directed parallel to each other but not along the same straight line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define torsion

A

Twisting of a body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define Bending/Flexure

A

Applied bending moment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define strain

A

change in length per original length of body when subjected to a load

Often reported as a %

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Deformation from tensile force causes what change to the axis?

A

Elongation in the axis of the applied force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Deformation from compressive forces causes what change in the axis?

A

Compression/ shortening of the body in the axis of loading

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is this called?

Define it

A

Stress-Strain Curve

relationship of dental material studied by measuring the load and deformation and then calculating the corresponding stress and strain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define A, B,

A

A: Proportional limits or elastic limits

Highest stress and which stress-strain curve is a straight line (i.e maximum stress that material will withstand WITHOUT permanent deformation)

B: Yield Strength

Point were material begins to functions in a plastic manner i.e. defines were transition from elastic to plastic behavior (estimates when material will start to deform permanently)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define C, D

A

C: Ultimate Tensile/Compressive Strength

Maximum stress that a material can withstand before failure in tension or compression

D: Fracture Strength

Point at which a brittle material will fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where is the elastic region?

Where is the plastic region?

A

area under 0-A = elastic region (able to return to normal length/ no deformation)

area under A-D = plastic region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define Elongation

A

Deformation that results from the application of tensile force

Give indication of possible manipulation of alloy

Total elongation is a %

Includes both elastic and plastic elongation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The material is more brittle at (lower/high) % of elongation?

A

Lower % = brittle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The material is more plastic/permanent elongated at (higher/lower) %?

A

Higher % = more plastic/permanent elongation (permanently bent WITHOUT danger of fracturing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Define Elastic modulus

A

Measures the elasticity of a material i.e. represents the stiffness of a material within the elastic range

Determined by the slope of the elastic portion of the stress-strain curve

Elastic Modules = stress/strain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

“A” is stiffer/rigid or flexible

“B” is stiffer/rigid or flexible

A

“A” is stiffer/rigid (metals/ceramics) because has a steeper slope

“B” is flexible (elastomers/polymers) because has a shallow/lower slope

25
Q

Define Ductility of a material

A

Enable it to be drawn (stretched) and shaped into wires by been of tension (think turning wool on a spindle)

26
Q

Define Malleability

A

Malleus = Hammer

Enables it to be hammered or rolled into thin sheets without fracturing (think sheet metal)

27
Q

(High/Lower) degree of elongation indicates good malleability and ductility

A

High degree of elongation indicates good malleability and ductility

28
Q

Metals tend to be (ductile/brittle)

A

Metals tend to be ductile

29
Q

Ceramics tend to be (ductile/brittle)

A

Ceramics tend to be brittle

30
Q

Define Resilience

A

Resistance of a material to permanent deformation

Measured by area under the elastic portion of the stress-strain curve (0-A)

31
Q

Define Toughness

A

Resistance of a material to fracture

Area under the elastic and plastic portions of the stress-strain curve (0-D)

Brittle material have low toughness because little plastic deformation occurs before failure

32
Q

Which graph(s) are stiff/rigid; which are flexible?

A

Stiffer: 1,2, 3, 4 (steeper slopes)

Flexible 5,6,7,8 (less steep slopes)

33
Q

Which graph represents the toughest material?

A

Graph 1 = has the greatest area under the curve

34
Q

Which graph(s) have the greatest resilience?

A

Graph 5,6 because have greatest area from (0-A)

35
Q

Which graphs have the highest strength?

A

Graphs 1, 2, 5, 6 have the highest proportional limit

36
Q

Which graphs have the highest ductility?

A

Graphs 1, 3, 5, 7 (longest to get to D)

37
Q

Which graphs have the highest stiffness AND strength?

A

1 and 2 (steepest with highest proportional limit)

38
Q

Which graph(s) have the greatest stiffness, strength, ductile?

A

Graph 1 (steepest, highest proportional limit, longest)

39
Q

Amalgam, cements, ceramics, plaster, stone are (weaker/stonger) in tension than in compression?

A

Amalgam, cements, ceramics, plaster, stone are weaker in tension than in compression

40
Q

Define viscoelasticity

A

Material that have the mechanical properties dependent on loading rate and exhibit both elastic and viscous behavior

41
Q

Define viscosity

A

Resistance of fluid to flow and equal to the shear stress divided by the shear strain rate

42
Q

Define Thixotropy

A

Describes the change in viscosity of a material with time

43
Q

Elastomeric impression material have (high/low) viscosity

A

Elastomeric impression material have high viscosity to stay in place without flow

44
Q

Define creep

A

Increase in strain in a material under constant stress

45
Q

(Greater or lower) creep makes a material more susceptible to strain accumulation and fracture

A

Greater creep makes a material more susceptible to strain accumulation and fracture

46
Q

Define Hardness

A

Resistance to permanent surface indentation or penetration

Resistance to plastic deformation

47
Q

Define Friction

A

Resistance between contacting bodies when on moves relative to another

48
Q

Define Wear

A

Loss of material resulting from removal and relocation of materials through contact of two or more materials

49
Q

What are the 4 types of wear?

A
  1. Adhesive wear
  2. Corrosive wear
  3. Surface fatigue wear
  4. Abrasive wear
50
Q

Define sol

A

Resembles a solution but made up of colloidal particles dispersed in a liquid (when chilled or reaction transforms into a gel)

51
Q

Define adsorption

A

ADsorption: liquid/gas adheres to the surface of the solid/liquid firmly by the attachment of molecules

52
Q

Define absorption

A

ABsorption: substance absorbed diffuses into the solid material by a diffusion process

53
Q

Do detergents (increase/decrease) surface tension of water?

A

Detergents decrease surface tension of water

Its hydrophilic part is in water and its hydrophobic end is in air/wax

54
Q

(Increasing/Decreasing) the surface tension (Increases/Decreases) wetting

A

Decreasing** the surface tension **Increases wetting

55
Q

Define Wetting power of liquid

A

Represented by its tendency to spread on the surface of the solid

56
Q

The greater the tendency to wet the surface, the (lower/higher) the contact angle

A

Lower

57
Q

Complete wetting occurs at what contact angle?

A

Zero

58
Q

What occurs of the contact angle of solder is too great?

A

There will be no penetration into the fine detail of structures to be joined

AVDC Flash Cards (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions