Brainscape's Knowledge GenomeTM

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


See full index

Tim's Cards > Fixed Q2 > Flashcards

Fixed Q2 Flashcards

1
Q

Once the impression is in stone what is it placed on

A

articultor

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

what material should the impression be poured up in

A

gypsum

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

Gypsum. when the semi hydrate is mixed with water, a suspension is formed that is ____ and ____

A

fluid and workable

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

the hemihydrate dissolves until what point

A

forms saturated solution

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

what does the hemihydrate solution precipitate out

A

dihydrate

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

Polymers…

Stone….

Wax…

A

shrink

expand

temp dependent

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

PIMWIC, what 2 stages shrink, what 2 expand?

A

Impression and Cast shrink

Mount and Investment Expand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Gypsum rxn: powder + water = stone + heat

or…

A

hemihydrate + water = dihydrate + unreacted hemihydrate + heat

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

In the gypsum rxn, there is dissolution of…

precipitation of….

as long as…

A

hemihydrate

dihydrate

new crystals form/current crystals grow

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

what is the use for slurry water

A

to make the stone set quicker

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

how is gypsum classified

A

1-5 for compressive strength

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

classify the following: mounting plaster, dental stone, model plaster, dental stone-high strength low expansion, dental stone-high strength high expansion

A

1,3,2,4,5

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

what is the difference between types 4 and 5

A

4 low expansion

5 high expansion

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

What does the slurry water add that makes the gypsum precipitate more quickly?

A

More sites of nucleation

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

Gypsum classificaiton, Type I

Type II

Type III

Type IV

Type V

A

mounting plaster

model plaster

dental stone

dental stone - high strength, low expansion

dental stone - high strength, high expansion

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

Describe the particles of Plaster (gypsum) Type I/II:

This is a _____ hemihydrate:

A

large, irregular particles

Beta

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

Describe the particles of Stone type III-V:

This is a ____ hemihydrate:

A

small, greater strength

alpha

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

3 effects of adding water to the gypsum powder:

A

Increases Setting time

Weaker

Less expansion

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

why is type 3 used for making dentures

A

the final step of denture making involves breaking the stone. type 3 is easier to break

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

what class of gypsum is used for making impressions on a pt and why

*diagnostic

A

III

cheaper

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

what class is used for crowns and bridges

A

4 or 5

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

what type of gypsum should be used for high shrinking base metals

A

type 5 because it can compensate because it has higher expansion

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

what type of gypsum does Ahwatukee lab use.

A

Excalibur - type IV

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

Why should a cast be soaked in water before trimming?

A

Easier to trim, clean up, rid of particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the advantages/disadvantages of the removable die system

A

advantages: it can get to all areas when doing a wax up. easier to fabricate.

Disadvantages: we have moving parts and movement can make contacts stronger or weaker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

why does the lab send back a solid metal

A

Verify seating/interproximal contacts

allows for better testing of inter proximal contacts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

3 ways we mount the 2 arches against each other

A

maxillo-mandibular jaw relation record

jaw relation record (JRR)

Bite registration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

In mounting the arches against each other, it is possible to hand articulate when?

What verifies the mounting?

A

If max intercuspation is stable

bite registration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

if MIP is not stable what is required to mount the cast accurately

A

bite registration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

2 types of Bite Registration matl:

A

Take 1

Regisil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Take 1 (bite reg. matl) Working Time:

Setting time:

Rigidity:

color:

A

15 secs

1 min.

extremely rigid

green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Regisil (bite reg. matl) Working Time:

Setting time:

Rigidity:

color:

A

45 secs

1 min. 30 secs

less rigid than Take1

purple

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Working time PVS:

Setting time PVS:

A

1 min 10 secs

5 min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Wax up: why do we mark the margin

A

to make sure we place it properly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the purpose of a die spacer?

A

To make room for cemet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Recommended space of die spacer:

comes in various thickness - but factors that influence amount of relief are the type of cement and _____

A

25-40 micrometers

TOC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

type 1 wax is ____ hardness and used for _____ technique for making patterns


A

medium

direct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

type 2 wax is ______ wax and used for _____ fabrication of castings

A

softer

indirect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Wax expands when heated, contracts when cooled and needs to be burned out cleanly leaving less than ___ % residue.

A

0.1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

T/F

The wax up should look like a tooth

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the function of the sprue?

A

Allows molten wax to escape from mold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

The design of the sprue must enable the molten metal to do what?

A

Flow in with little turbulence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

where should the sprue be attached and what is a common placement

A

the bulkiest noncritical part and the non functional cusp is usually used

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How far is the wax pattern usually placed from the top of the investment?

A

6 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What is the sprue attached to?

A

crucible and casting ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

The metal within the sprue remains molten slightly longer than the alloy that has filled the mold, providing a ____ to compensate for the shrinkage that occurs during solidification

A

reservoir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What factors influence the expansion of the investment?

A

Liner

Ring/Ringless

Setting, hygroscopic, thermal expansion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Adding liners allows for more expansion of the ______

A

investment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Ringless design allows for what?

A

unrestricted expansion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Hygroscopic expands the most, and is accomplished by doing what?

A

submerging ring in 100 degree F water bath for 1 hr immediately after investing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

T/F

In order of increasing Investment expansion: Normal, 1 liner, 2 liner, Hygroscopic

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

3 requirements of Investment matl:

A

Precisely reproduce wax up

Strong enough for heat and casting

Expand to compensate for alloy shrinkage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What 3 binding matls regulate Rigidity of the Investment?

A

Gypsum

Phosphate

Ethyl Silicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What regulates thermal expansion of the Investment matl?

refractory

A

Silica

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What Investment matl is generally used only for Gold b/c it can’t be heated above 650 C?

*not used much any more

A

Gypsum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What Investment matl can be heated above 650 C but has rough casts and is difficult to remove?

A

Phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What Investment matl is used for high fusing base metal partial denture alloys

A

Ethyl silicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What type of investment material do we use at ASDOH

A

GC fujivest II which is a phosphate bonded investment that can withstand high temps.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

GC fujifest II (Investment matl) working time:

Setting time:

A

6 mim

20 min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How are metal alloys classified?

A

Noble metal content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Why do we use noble metals?

A

Stable, don’t corrode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

High noble alloy:

A

40% Au

60% nobles

*by weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Noble alloy:

A

25% noble

*by weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Predominately Base Metal:

A

less than 25% noble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

7 Noble metals:

A

Au, Pt, Pd, Rh, Ru, Ir, Os

66
Q

Elastic Modulus =

A

Stress/Strain

rise/run

67
Q

The stress at which a matl shows a specific amount of plastic strain:

A

Yield strength

68
Q

Classify metal ceramic crowns: Argebond 80

Argedent Euro

A

Noble

High noble

69
Q

Classify Full Gold Crown: Argenco 56

Argenco Y+

A

High noble

Noble

70
Q

What kind of bur would you use to cut through porcelain, metal?

A

Porcelain - diamond

Metal - carbide

71
Q

High noble, Melting temp:

Shrinkage:

Castability:

Hardness

Corrosion:

A

lower

less

better

softer

less

72
Q

PVS shrinks and is hydrophobic

A

True

73
Q

When doing investments what does gypsum, phosphate, and ethyl silicate determine?

A

Temperature

74
Q

When doing investment what does quartz cause?

A

Expansion

75
Q

What are the 3 properties of Excalibur Type IV mounting material that we use at ASDOH?

A

quick setting

low strength

low expansion

76
Q

PVS differentiated by viscosity

stone (I-IV) by strength

Investment by matl (gypsum, phosphate, ethyl silicate, quarz/cristobiolite)

Cast by Nobility

A

True

77
Q

Lowest point of the Orbitale to highest point of the external auditory meatus

A

Frankfort Horizontal Plane

78
Q

How should the Frankfort horizontal plane be aligned with the floor?

A

Parallel

79
Q

What acts as the 3rd point of reference (1. upper margin ext. aud meatus. 2. lower orbitale)

A

Nasion

80
Q

The average distance between the Nasion and the Frankfort horizontal plane?

A

23 mm

81
Q

What is the purpose of the Facebow?

A

Position Max cast onto articulator relating to pts hinge axis in 3 dimensions

82
Q

The path of the condyle follows what?

A

Articular Eminence

83
Q

As the condylar inclination increases what also increases?

A

Space between posterior teeth in disclusion

84
Q

What allows the mandibular movements of the articulator to simulate the movement of the mouth?

A

Facebow record

85
Q

3 things captured in triple tray:

A

opposing arch

jaw relation

prep (and adjacent teeth)

86
Q

In group function what teeth contact in laterotrusive movement?

A

posterior

87
Q

Why are we less concerned if pt has canine guidance?

A

posterior teeth don’t contact each other in laterotrusive movement

88
Q

What is the anatomical average Condylar Guidance Angle?

A

25-30 degrees

89
Q

What info is lost using a triple tray?

A

guidance in non-working movement

relationship between teeth and hinge axis

canine guidance

90
Q

What are the advantages to using a triple tray?

A

Minimize use of impression matl

no need for separate impression of opposing arch

jaw relationship w/ PDL in compression

91
Q

T/F

A fully adjustable articulator can move condyles, ours can’t

A

True

92
Q

In what type of articulator dose the condylar inclination stay the same?

A

Arcon

*we have arcon

93
Q

An Arcon articulator has the condyle on the ______, while a non-Arcon has the condyle on the ______

A

Mandible

Maxilla

94
Q

In an Arcon articulator, when you open the pin in a vertical dimension, what happens to Vertical Dimension?

Condylar inclination?

A

Increases

Stays the same

95
Q

Changing the vertical dimension in an Arcon articulator will not change the angle

A

True

96
Q

What are 5 contraindications to using a triple tray?

A

Multiple fixed units

Fixed partial denture

survey crown

Class 2 and 3 occlusion

Implants

97
Q

Which articulator do we currently use?

A

Arcon

98
Q

What establishes the chemical bond between the Metal and Porcelain?

A

Controlled Oxide layer

99
Q

How do we create an Oxide layer so porcelain can bond to metal?

A

Put in oven

100
Q

What type of metal has a controlled oxide layer?

What is uncontrolled?

What is a side effect of uncontrolled oxide layer?

A

Nobles

Bases

Bad adhesion

101
Q

5 Steps to adding Porcelain onto metal:

*in decreasing temperature

A

Oxidize

Opaque (blocks out metal color)

Margin

Dentin

Glaze

102
Q

Why do all the steps of adding porcelain decrease in temperature?

A

Sintering

103
Q

What has a higher CTE (coefficient of thermal expansion) - porcelain or metal?

A

Metal

104
Q

What are the 2 phases of Feldspar?

A

Glassy

Crystalline

105
Q

If something is 100% gold, could you stack porcelain?

A

Would be difficult b/c doesn’t readily form oxide layer

106
Q

What 2 factors influence the amount of die spacer we use?

A

Type of cement

TOC

107
Q

How does TOC affect the space in a die spacer?

A

Less TOC, more die spacer

*If a lot of TOC (lots of taper), cement will flow and less die spacer needed

108
Q

What 4 elements are often added to Noble metals to ensure an Oxide Layer forms?

A

Iron

Tin

Indium

Gallium

109
Q

Base metals are principally ______ and _______

_______ oxidation provides chemical bonding for porcelain adherence

A

Nickel, Cobalt

Chromium oxidation

110
Q

T/F

Base metals used for metal-ceramic restorations go through continuous oxidation

A

True

111
Q

What can the continuous oxide formation by base metals cause?

A

Potential failure via a Thick Oxide Layer that can’t be controlled

112
Q

The oxide layer close to the surface is mostly made up of what element?

A

Silica (Si)

113
Q

What is the main raw component of dental porcelains?

A

Feldspar

114
Q

What does Feldspar look like in its mineral state?

A

Crystalline and opaque

115
Q

2 Types of Feldspar:

A

Potassium aluminosiclicate “potash feldspar”

Sodium aluminosilicate “soda feldspar”

116
Q

Most veneering ceramics are derived from what type of feldspar?

A

Potash

Potassium aluminosilicate

117
Q

Feldspathic Porcelain exists in what 2 phases?

A

Glassy (silica)

Crystalline (leucite)

118
Q

What phase of Feldspathic porcelain provides strength?

A

Crystalline

119
Q

Describe both phases of Feldspar:

A

Glassy: high translucency

Crystalline: strength

120
Q

How much of Feldspar is made up of the Crystalline phase?

A

15-25%

121
Q

T/F

Porcelain is stronger when in compression

A

True

122
Q

The process of forming a solid mass by heat/pressure without melting to lequefaction

A

Sintering

123
Q

4 Steps to the Firing Chart:

High to low temp

A

Opaque

Margin

Dentin/Mod/Enamels

Glaze

124
Q

Why would a thick oxide layer cause fracture?

A

Not as strong, if too thick of a hybrid layer can cause structural problems

125
Q

What is a problem of sintering porcelain?

What is a solution?

A

Fused mass too viscous to allow air to escape = Trapped air/voids

Vacuum firing

126
Q

What is the purpose of the Opaque Layer?

A

Block the metal from view

127
Q

What has a higher thermal expansion - porcelain or metal?

A

Metal

128
Q

Because the metal contracts more during cooling than porcelain, this creates what?

A

Porcelain in slight residual compression

129
Q

T/F

Porcelain does well under tensile stress and not well under compression

A

False

*Porcelain does well under compression - flat marginal ridge

130
Q

What makes porcelain less sensitive to the tensile stresses induced by mechanical loading?

A

Residual compression due to metal shrinking more on cooling

131
Q

Bond failures between 2 materials:

Bond failures within a dental material:

A

Adhesive failure

Cohesive failure

132
Q

Fractures at the metal to metal/oxide layer is a _______ failure and commonly observed with poor ________

A

adhesive

bonding

133
Q

Why would a fracture occur through the oxide layer?

A

If oxide layer too thick

*cohesive failure in METAL

134
Q

If everything is properly bonded, where would a fracture occur in a metal/porcelain crown?

A

Porcelain

*cohesive

135
Q

Dipping a die into molten wax produces an Even Thickness - doing what to the porcelain layer?

Consequence:

A

Makes uneven

porcelain fractures due to lack of support

136
Q

For predictable success in creating an even porcelain layer onto the metal, use a _____ technique

A

Cut-back

from full contour wax up

137
Q

2 Aqueous Hydrocolloids:

3 Non-aqueous Elastomers

(these are the Elastic categories)

A

Agar, Alginate

Polysulfide, Polyether, PolyVinyl Siloxane (Condensation/addition)

138
Q

What non-aqueous elastomer is Hydrophilic and rigid, with a defined working time (“snap set”)?

A

Polyether

139
Q

Bottom cord should be what size?

Top cord?

A

small - 000 or 00

larger - 0

140
Q

Cords are typically soaked in what?

A

Hemostatic agent

141
Q

2 techniques for Gingival Retraction other than cord:

A

Expasyl - paste

Laser

142
Q

Advantages to a Supragingival margin:

Disadvantages:

A

No cord, verify margins

Not esthetic, tooth structure exposed

143
Q

Advantages to an Equigingival margin:

Disadvantages:

A

minimal retraction

recession will expose margin

144
Q

Advantages to a Subgingival margin:

Disadvantages:

A

Esthetics

Retraction difficult

145
Q

7 Requirements for Provisional Restorations:

A

Pulpal protection

Positional stability

Occlusal function

Ease of cleaning

Nonimpinging margins (overhangs, etc)

Strength/Retention

Esthetic

146
Q

If you haven’t reduced the occlusal surface enough, the lab sends you…

A

Reduction Coping

147
Q

A lab prescription should have what 3 surfaces specified for a restoration?

*and another thing:

A

Facial

Occlusal

Lingual

*shade of porcelain

148
Q

Facial and Occlusal surfaces can be in what materials?

Lingual?

A

Porcelain or metal

metal

149
Q

When will the lab send you a 360 metal collar?

A

When facial/lingual surfaces both in metal

150
Q

T/F

360 metal collar has the best marginal integrity

A

True

151
Q

4 cases in which the used of metal over porcelain on the occlusal surface:

A

Bruxism

Large mm.

Hx porcelain fracture

Most posterior tooth

152
Q

Why would the most posterior tooth not get a porcelain occlusal restoration?

A

Teeth shorter - not enough pulpal room for big reduction

153
Q

The vasoconstrictor for cord is usually:

Viscostat:

Viscostat clear:

A

Aluminum chloride

Ferric sulfate

Aluminum chloride

154
Q

Pack 2 cords and take the top out after __ minutes. You need a clean, dry, field.

A

5

155
Q

If making an FMC do the final impression using _______, then look for bubbles/clean margin

A

Custom tray

156
Q

Why can’t you do a bite registration off of a stone cast?

A

Has expanded

157
Q

What shrinks more - noble or base metals?

What must you use to offset the higher shrinkage?

A

Base

Type V dental stone

158
Q

Casts (yellow) are in Type ____

Plaster (white) that connects to the Articulator is Type _____

A

3

1

159
Q

In posterior teeth, porcelain tends to fracture where?

A

Marginal Ridges

160
Q

Ringless means a _____ ring and allows for expansion of ______

A

Plastic

Investment

161
Q

Invest, Cast - then break, cut off Sprue. If metal - you’re good. If stacked to porcelain, then _______

A

Coping

162
Q

What do you have to do to the prep before you wax?

A

Lube

Tim's Cards (140 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions