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BDS2 > Prosthodontics > Flashcards

Prosthodontics Flashcards

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1
Q

Define an articulator

A

Reproduces occlusal relationship between the maxilla + mandible

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2
Q

2 extra oral consequences of missing teeth

A

TMJ problems

Changes in facial appearance

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3
Q

Why does facial appearance change due to missing teeth

A

Lack of downward pressure on alveolar bone causes bone loss

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4
Q

2 changes in facial appearance due to missing teeth

A

Maxilla regresses

Mandible protrudes

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5
Q

3 intra oral consequences of missing teeth

A

Alveolar resorption
Tooth movement
Tooth wear

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6
Q

2 functional consequences of missing teeth

A

Mastication

Speech

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7
Q

3 types of complete dentures

A

Removable
Implant retained
Implant supported

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8
Q

Describe implant retained complete dentures

A

Implants allow denture to ‘snap in place’

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9
Q

Describe implant supported complete dentures

A

Non removable and screw retained

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10
Q

2 types of saddle

A

Free end saddle

Bounded saddle

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11
Q

How many teeth are needed for function

A

20

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12
Q

Kennedy class 1

A

Bilateral free end saddles

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13
Q

Kennedy class 2

A

Unilateral free end saddle

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14
Q

Kennedy class 3

A

Posterior bounded saddle

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15
Q

Kennedy class 4

A

Anterior bounded saddle crossing midline

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16
Q

What does the Kennedy class describe

A

Distribution of missing teeth

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17
Q

What does the Craddock class describe

A

Denture’s resistance to occlusal directed load

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18
Q

Craddock class 1

A

Tooth support

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19
Q

Craddock class 2

A

Mucosa support

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20
Q

Craddock class 3

A

Mixed support

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21
Q

Describe what tooth support requires

A

Support on both adjacent abutment teeth

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22
Q

What is a shorted dental arch

A

No treatment option for those with missing posterior teeth

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23
Q

How many occlusal units does a shortened dental arch need for sufficient adaptive capacity

A

3-5 units

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24
Q

How many occlusal units is an occluding premolar worth in relation to a shortened dental arch

A

1 unit

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25
How many occlusal units is an occluding molar worth in relation to a shortened dental arch
2 units
26
What teeth should you prioritise maintaining in a shortened dental arch
Anterior teeth + premolars
27
Advantage of tooth supported dentures
Don't sink into tissues
28
Define support in relation to RPD's
Resistance to vertical movement towards tissue
29
Define retention in relation to RPD's
Resistance to vertical movement away from tissue
30
Define stability in relation to RPD's
Resistance to horizontal movements
31
Define freeway space
Space between teeth at rest
32
4 checks for abutment teeth in RPD's
Sound structure Good edentulous ridge Good roots Good alveolar bone
33
3 special tests for abutment teeth in RPD's
Periapical radiographs Sensibility testing Surveyed study models
34
2 base materials for RPD's
Cobalt chrome | Acrylic
35
Define a flange in relation to RPD's
Replacement tissue
36
Where does the flange in RPD's extend to
Vestibular sulcus
37
What is a modification in relation to the Kennedy class
An extra saddle
38
Which Kennedy class cannot have a modification
Class 4
39
What occlusal load can a healthy tooth carry
It's own load + 1.5 similar teeth
40
List the teeth in order of load bearing from highest to lowest
Molars Canines Premolars Anteriors
41
Compare PDL support of an RPD compared to mucosa support
PDLs support is > 4 times the mucosal coverage of lost tooth
42
How far should RPD components be from the gingival margin
3mm
43
What is a characteristic of the Every RPD design
Wire stop on most posterior teeth
44
What is the function of a wire stop in RPD's
Ensure distal tooth won't drift posteriorly
45
What is the compressibility of the periodontium
0.1mm
46
What is the compressibility of the mucoperiosteum
2mm
47
What is the periodontium
Tooth attachment in the socket
48
What is the mucoperiosteum
Mucosal coverage of alveolar bone
49
Where is primary support in Craddock class 2/3 RPD's
``` Upper = central palate Lower = buccal side of saddle areas ```
50
Where is secondary support in Craddock class 2/3 RPD's
``` Upper = anterior palate + saddle areas Lower = central + lingual side of saddle areas ```
51
How do you know if tooth support is sufficient for RPD's
Missing teeth total root area < max load
52
How do you find the max load of abutment teeth in RPD's
Cumulative root area of abutment teeth X 1.5
53
What do rests do in RPD's
Oppose denture base compressing tissues
54
How are different rest described in RPD's
By the part of the tooth they contact
55
Where would cingulum rests be found
Anterior teeth
56
3 advantages of cingulum rests over incised rests in RPD's
Better aesthetics Stress applied lower causing less rotation No occlusion interference
57
3 types of rests in RPD's
Cingulum Incisal Occlusal
58
What is the most favourable type of rest
Occlusal
59
Where are rests placed for a bounded saddle in an RPD
Directly adjacent to saddle
60
Where are rests placed for a free end saddle in an RPD
Mesially
61
What material are rests made of
Cast metal
62
2 properties of cobalt chrome denture base
Rigid | Strong
63
2 properties of acrylic denture base
Flexible | Weak
64
How are rests connected to cobalt chrome base dentures
Directly connected to major connector or by minor connectors
65
How are rest connected to acrylic base dentures
Incorporated mechanically
66
3 ways of achieving retention in RPD's
Mechanical Muscular Physical
67
What is the mechanical method of retention in RPD's
Clasps
68
What is a clasp made of for = RPD's
Wrought metal
69
2 types of clasps in RPD's
Gingivally approaching | Occlusally approaching
70
What teeth would you use gingival approaching clasps on in RPD's
Anteriors + premolars
71
What is a clasp in RPD's
Metal arm that retains denture in mouth
72
Why is a clasp linked to a rest more effective in RPD's
Rest prevents clasp slipping down tooth
73
What is the muscular method of retention in RPD's
Muscles act on the shape of the denture base
74
What is the physical method of retention in RPD's
The coverage of the mucosa
75
3 forces involved in the physical method of retention in RPD's
Adhesion Cohesion Atmospheric pressure
76
Define adhesion in relation to RPD's
Surface force of saliva on denture + mucosa
77
Define cohesion in relation to RPD's
Forces within saliva + viscosity
78
Define atmospheric pressure in relation to RPD's
Resistance to displacing factors
79
2 classification of of retention in RPD's
Direct | Indirect
80
Define direct retention in RPD's
Denture's resistance to vertical displacement
81
Define indirect retention in RPD's
Denture's resistance to rotational displacement
82
Where should direct retention be in RPD's
Close to base of adjacent abutment teeth
83
What is a supplementary method of direct retention in RPD's
Guide planes
84
Where should guide planes be in RPD's
Close to base of abutment teeth + parallel to path of insertion
85
5 types of indirect retainers in RPD's
``` Major connectors Minor connectors Rests Saddles Denture base ```
86
What is the clasp axis in RPD"s
Axis of rotation
87
Where should indirect retention be placed in RPD's
Perpendicular to axis of rotation
88
What is a reciprocating arm in RPD's
Opposing element to each clasp unit
89
What does a reciprocating arm do in RPD's
Prevents clasp pressure acting on tooth + moving it
90
What does the path of insertion allow in RPD's
Anterior retention without clasps
91
What is the ideal pattern of retention in RPD's
Triangular
92
What is the pattern of retention in RPD's
Number of retainers in an arch
93
What colour are saddles in the system of deign of RPD's
Yellow
94
What colour is support in the system of deign of RPD's
Red
95
What colour is retention in the system of deign of RPD's
Green
96
What colour is bracing + reciprocation in the system of deign of RPD's
Blue
97
What colour are connectors in the system of deign of RPD's
Black
98
What is an RPI RPD
Stress relieving clasp system
99
Where are RPIs used in RPD's
Free end saddles
100
Why are RPI's ideal for free end saddles in RPD's
Prevent stress on last abutment tooth
101
3 parts of an RPI in RPD's
Mesial occlusal rest Proximal guide plate adjacent to saddle Gingivally approaching I-bar clasp
102
What is a proximal guide plate in an RPI RPD
Guide surface of 2-3mm undercut
103
Where does the gingival approaching I-bar clasp contact the abutment tooth of an RPI RPD
Greatest prominence of tooth contour
104
What Kennedy class is an RPI ideal for in RPD's
Class 1 lower denture
105
Define the major connector of RPD's
Rigid part connecting components on both sides of an arch
106
2 types of major connector design of an RPD
Closed | Open
107
2 advantages of a major connector closed designing RPD's
More contact withe adjacent teeth | Greater retention
108
What is necessary for a closed design major connector in RPD's
Guide planes
109
2 advantages of an open design major connector in RPD's
No gingival coverage | Saliva clearance
110
How can a major connector add indirect retention to an RPD
Extend major connector to resist functional forces
111
2 things beading of a major connector do in RPD's
Intimate contact between denture + tissue | Prevents food ingression
112
Where is beading of a major connector in RPD's
Along border but stops 3mm from gingival margin
113
How thick should the cross section of a plate major connector be in RPD's
0.5mm
114
What Craddock class is a plate major connector often used for in RPD's
Class 2 designs
115
What is an advantage of a bar major connector in RPD's
Less mucosal coverage
116
What Craddock class is a bar major connector often used for in RPD's
Class 1 designs
117
5 cobalt chrome maxillary major connector designs for RPD's
``` Anterior Mid palatal Anterior/posterior bar (ring) Horseshoe Posterior palatal ```
118
2 benefits of ring major connector in RPD's
Rigid | Wide relief of gingival margins
119
2 disadvantages of ring major connector in RPD's
Uncomfortable due to many edges | Thicker cross section
120
What is another name for the ring major connector in RPD's
Anterior/posterior bar
121
8 acrylic maxillary major connector designs for RPD's
``` Anterior Mid palatal Full coverage Horseshoe Posterior palatal Spoon Modified spoon Every ```
122
What is the state of oral cavity would those getting acrylic upper major connector RPD's
Few or weak teeth
123
What is the default choice of mandibular major connector in RPD's
Lingual bar
124
Why would a lingual bar mandibular major connector be used in RPD's
Lingually inclined anterior teeth
125
5 mandibular major connectors in RPD's
``` Lingual bar Lingual plate Dental bar Sublingual bar Labial bar ```
126
How much space should be left between major connector + gingival margin in mandibular RPD's
3mm
127
How much space should be left between mandibular major connector + functional floor of mouth RPD's
1mm
128
Define the minor connector of RPD's
Rigid connector joining components to the major connector
129
What does the minor connector do in RPD's
Transfer functional stress to + from abutment teeth
130
3 guidelines of minor connectors in RPD's
Finish above survey line Cross gingival margin perpendicularly Cover little gingival tissue
131
What kind of retention joins the gland to base of RPD's
Mechanical retention
132
2 reasons a stop is needed to attach teeth to edentulous areas of RPD's
Checks fit | Ensure no rotation
133
If there is restricted vertical space in an edentulous area what alteration is used when attaching the flange to the base in RPD's
Metal plate contacts mucosa
134
When is a post used in RPD's
If insufficient space for retention mesh in base
135
Why are lower incisors set with space in relation to upper incisors in RPD's
Avoid pressure on fake tooth
136
What is incorporated if limited space between incisors in RPD's
Metal backing
137
Why is metal backing incorporated to incisal teeth in RPD's
Provide occlusal contact while preventing pressure causing upper tooth debonding
138
What is the thickness of rests in RPD's
0.5-1mm
139
Where is a rest thickest in RPD's
Junction with minor connector
140
What is the height + thickness of a lingual bar in RPD's
4mm height | 2mm thickness
141
What is the thickness of a sub lingual bar in RPD's
4mm
142
What is the depth + with of a bead on a maxillary major connector in RPD's
0.5mm depth | 1mm width
143
What is the withe + thickness of a bar maxillary major connector in RPD's
6mm width | 1.5mm thickness
144
What is the thickness of a plate maxillary major connector in RPD's
0.4mm minimum
145
What is the width + thickness of minor connectors in RPD's
2mm width | 1.5mm thickness
146
What is the length of a cast clasp in RPD's
15mm to engage 0.25mm
147
What is another name for beading of a RPD major connector
Pin/post dam
148
What should the clearance from the gingival margin in maxillary major connectors be in RPD's
5mm
149
2 aims of 1st visit for RPD's
Assessment | Primary impressions
150
3 things to assess in 1st visit for RPD's
Ridge form Saddle Undercuts
151
3 decisions to make when doing primary impressions for RPD's
Tray selection Type of impression material Whether to record occlusion
152
What material do you use for primary impressions of bounded saddles in RPD's
Alginate
153
What material do you use for primary impressions of free ended saddles in RPD's
Alginate | Compound
154
Where is compound used in primary impressions in RPD's
Free end saddles
155
Why is compound added to free ended saddles in primary impressions for RPD's
Stabilise tray
156
What do you disinfect impressions in for RPD's
Perform
157
How long do you disinfect impressions for in RPD's
10 minutes
158
What do you do after disinfecting impressions for RPD's
Rinse impressions + add to sealed bag
159
What do you add to the bag with impressions for RPD's
Wet cotton wool
160
When should you record the occlusion for RPD's
When unable to hand articulate
161
3 instructions you give the technician after the primary impressions visit for RPD's
Pour primary cast Produce special tray + spacer Produce primary record block for preliminary registration
162
What should be done before the master impressions visit for RPD's
Survey casts | Draw design on lab card
163
What do you do if there is no interocclusal space for a rest seat in RPD's
Make space by cutting a rest seat
164
What do you do after the primary impressions visit for RPD's
Master impressions
165
What 2 things do you do in the master impressions visit for RPD's
Try in special tray | Take master impressions
166
4 types of impression material for RPD's
Poly vinyl siloxane (PVS) Polyether Alginate Compound
167
2 instructions for technician after the master impressions visit for cobalt chrome RPD's
Pour mode in improved stone | Construct chrome frame work
168
2 instructions for technician after master impressions visit for acrylic RPD's
Pour model in stone | Construct record block with shellac base (if doing occlusion)
169
2 things to do after the master impressions visit for RPD's
Record occlusion | Framework trial
170
4 things to check framework of RPD's
Fits cast well Seats well in mouth Any interference with occlusion Is cast damaged
171
What do you use to adjust clasps for RPD's
Adam's pliers
172
Define a conformist approach to RPD's
Keeping the same occlusion
173
Define a re organised approach to RPD's
Change the occlusion
174
3 aims of establishing occlusion in RPD's
Establish inter occlusal relationship Establish occlusal vertical dimensions Tooth mould
175
2 measurements if no index teeth are present for RPD's
Occlusal vertical dimensions | Free way space
176
Instruction for technicians after recording occlusion visit fro RPD's
Produce record block on framework
177
3 decisions for tooth selection of RPD's
Shade Mould Tooth arrangement
178
instructions for technicians after framework trial visit for RPD's
Set teeth for wax trial providing shade + mould
179
What type of articulator should you use in RPD's
Average value articulator
180
What do you choose during the framework trail visit for RPD's
Shade | Mould
181
Instructions for technician after recording occlusion visit for RPD's
Produce wax record blocks on framework | Articulate casts
182
6 reference points for placement if anterior teeth for RPD's
``` Teeth present Dento-facial midline Inter pupillary line Ala-tragus line Smile line Lower lip curvature ```
183
What do you do after the framework trial visit for RPD's
Tooth trial
184
4 checks during tooth trial visit for RPD's
Framework fit Occlusion Aesthetics Extension
185
Instruction for technicians after tooth trail visit for RPD's
Finish in acrylic
186
What do you do after the tooth trial visit for RPD's
Deliver final RPD
187
4 checks for the final denture on the articulator for RPD's
Proper seating Articulator pin on table Correct occlusion Correct design
188
6 checks for final denture in mouth in RPD's
``` Correct seating Stable Rest seats correct Clasps correct Occlusion correct Aesthetics ```
189
4 instructions for patient in final delivery of RPD visit
Check ability to insert + remove May have altered speech + pain Denture cleaning Give patient information leaflet
190
What do you do after the delivery of final RPD visit in RPD's
Review + adjust
191
What do you use to record occlusion on record blocks in RPD's
Silicon registering paste
192
4 stages of a restorative treatment plan
Immediate treatment Hygienic phase Corrective phase Maintenance
193
Main goal of immediate treatment
Reduce pain
194
Main goal of hygienic phase
Take up good habit or lifestyle changes
195
3 aims when setting teeth for RPD's
Restore arch Restore aesthetics Restore function
196
What effect does base material have on setting teeth in RPD's
No effect
197
2 materials for teeth in RPD's
Plastic | Porcelain
198
Which tooth material has a chemical bond with denture base
Plastic
199
How is a porcelain tooth retained in a denture
Mechanical retention
200
What is the mechanical retention for an anterior porcelain tooth in a denture
Metal pin on the back
201
What is the mechanical retention for a posterior porcelain tooth in a denture
Hollowed areas filled with denture base material
202
Which tooth material has silent function in dentures
Plastic
203
Which tooth material has a high abrasion resistance for dentures
Porcelain
204
What does a low abrasive resistance allow for teeth in dentures
Easy to trim
205
4 variants between different tooth moulds for dentures
Shape Cuspal angle Space between canines Length + width of central incisor
206
Where do you trim teeth for dentures from
Ridge lap
207
Where is the ridge lap on a fake tooth for dentures
Part near gingival margin
208
What do you use to trim the ridge lap of fake teeth for dentures
Diamond cutters
209
Disadvantage of trimming ridge lap of fake teeth for denture
Reduced bonding area sleazier to break off
210
2 methods of bonding fake teeth to dentures
Heat cure | Self cure
211
4 guidelines when bonding teeth to denture
Start at midline Accommodate space + symmetry Don't overlap teeth Set teeth at long acid of corresponding tooth
212
If there is no space for a premolar what can be substituted in it's place on a denture
3rd premolar
213
4 things to prevent debunking of teeth on a denture
Use post for retention No grease on teeth No mould seal when processing Avoid heavy contact on denture teeth
214
6 reasons to do mouth preparation
``` Initial prosthetic treatment Surgery Periodontal treatment Orthodontic treatment Fixed prosthodontics tretemnemt + endodontics Tooth preparation ```
215
4 types of mouth preparation for initial prosthetic treatment
Repairs/additions Temporary reline denture Occlusal adjustment Treat denture stomatitis
216
2 advice for treating denture stomatitis
Cleanse | Remove at night
217
5 mouth preparations for surgery
``` Remove retained roots Remove unerupted teeth remove pathologies Improve edentulous area contours Eliminate fraenal attachments ```
218
When would you do periodontal surgery
With pockets > 6mm
219
4 mouth preparations for periodontal treatment
Establish periodontal tissue health Assess motivation Instruct oral hygiene procedures Scale + root planing
220
2 mouth preparations for orthodontic treatment
Optimise space | Optimise abutment alignment
221
2 mouth preparations for tooth preparation
Establish integrity of teeth before master impression | Provide guide planes + rest seats
222
What hand piece do you use during tooth preparation
Slow speed hand piece
223
What bur do you use to shape enamel surfaces in tooth preparations in RPD's
Rotary diamond bur
224
3 burs to use to smooth + polish roughened surface for tooth preparation in RPD's
Special burs Stones Abrasive impregnated rubber wheels points
225
Main point of tooth preparation for RPD's
Avoid denture components interfering with occlusion
226
How would you provide rest seats for maxillary anterior teeth
Cut into cingulum
227
How would you provide rest seats for mandibular anterior teeth
Build rest seat on cingulum
228
Why do you build the rest on the cingulum of anterior mandibular teeth instead of cutting one
Small cingulum makes it easy to penetrate enamel
229
2 materials to build rests on cingulum of anterior mandibular teeth
Composite | Cast metal
230
What shape should rest seats be on posterior teeth
Saucer shaped
231
Why are posterior rest seats saucer shaped
Allows some horizontal movement to dissipate occlusal forces
232
How deep should rest seats be on posterior teeth
Allow a rest of 1mm
233
4 reasons to use guide planes in RPD's
Easier insertion Increase stability reciprocation Improved aesthetics
234
Why do guide planes allow easier insertion of RPD's
Limit the path of insertion
235
How much enamel should be removed when preparing guide planes
<0.5mm
236
What height should guidelines be
3mm vertically
237
4 tooth preparations for RPD's
Provide rest seats Establish guide surfaces Modify unfavourable survey lines Creat retentive areas
238
How are retentive areas produced in tooth preparation for RPD's
Add composite to teeth
239
2 types of composite used to create retentive areas for RPD's
Ultrafine composite | Hybrid composite
240
Why would you modify unfavourable survey lines in tooth preparation for RPD's
Clasp is too close to occlusal surface and causes occlusal interference
241
Which impression material is not dimensionally stable
Alginate
242
3 things to check a master impression contains for an RPD
Frenulum Rugae on palate Teeth present
243
What is the tooth mobility scale is used
Miller tooth mobility
244
What is 0 on the Miller tooth mobility scale
Stable tooth
245
What is 1 on the Miller tooth mobility scale
< 1mm buccolingual movement
246
What is 2 on the Miller tooth mobility scale
1-2 mm buccolingual movement
247
What is 3 on the Miller tooth mobility scale
> 2mm buccolingual movement
248
3 investigations always done on a trauma patient
Sensitivity + vitality test Mobility test Radiograph
249
What technique is used to make cobalt chrome RPD's
Lost wax technique
250
Describe 4 stages of the lost wax technique for producing metal RPD's
Produce wax shape of RPD Surround wax shape with mould Melt wax to remove wax from mould Fill mould with molten metal
251
What kind of cast does the last wax technique involve
Refractory cast
252
What is a refractory cast made of
Phosphate bonded investment
253
Describe the heating of the refractory cast in metal RPD production
Heat at 200C for 45 minutes
254
What effect does heating have on the refractory cast during metal RPD production
Surface wear
255
What 2 things are done to the refractory cast before creating the wax pattern in production of metal RPD's
Heat model | Harden surface
256
3 types of model hardeners used in the production of metal RPD's
Beeswax Resin Aerosol
257
How long should the refractory model be cooled before the wax pattern stage in the production of metal RPD's
15-20 minutes
258
Describe how to use beeswax as a model hardener in the production of metal RPD's
Heat model | Dip in hot wax
259
Describe how to use resin as a model hardener in the production of metal RPD's
Heat model | Dip in cold resin
260
Describe how to use aerosol as a model hardener in the production of metal RPD's
Spray cold model
261
3 stages of making the maxillary plate wax pattern in the production of metal RPD's
Adapt 0.2mm wax sheet over the centre of the plate Adapt 0.5mm wax sheet in 2 halves over plate outline Burnish halves together
262
Where does the wax retention pattern attach in the production of metal RPD's
Close to the major connector
263
What joins the wax retention pattern to the major connector in the production of metal RPD's
Joining wax
264
What is the external finishing line in the production of metal RPD's
Fiishing line for acrylic
265
What kind of wax is the external finishing line in the production of metal RPD's
Round profile wax smoothed
266
Why would you add posts for anterior teeth in the production of metal RPD's
Due to limited retention
267
What happened when the mesh is thinner in saddle areas in the production of metal RPD's
A miscast
268
Describe the wax patten for clasps in the production of metal RPD's
Draw wax outline over prepared ledges
269
How do you ensure the clasp meets the major connector at the thickest part in the production of metal RPD's
Fill the mesh to the clasp attachment to join to the major connector
270
2 things sprues prevent in the production of metal RPD's
Air turbulence | Air trapping
271
What do sprues do in casting in the production of metal RPD's
Contact molten metal into the mould
272
Where do you attach sprues in casting in the production of metal RPD's
Thickest external finishing line closest to metal ingress
273
What is the sprue attached to in casting in the production of metal RPD's
Plastic cone aligned to a casting machine
274
What is higher: the wax pattern or the cone and sprue attachment in casting in the production of metal RPD's
Con + sprue attachment
275
Why do you progressively cool from the exterior towards the metal inflow centre in casting in the production of metal RPD's
Prevent cooling shrinkage
276
What des cooling shrinkage cause
Voids in casting
277
What do you do in the investing stage of casting in the production of metal RPD's
Prepare a mould around the refractory cast
278
2 components of the mould former in the investment stage of casting in the production of metal RPD's
Base + ring shape
279
What is the function of the ring shape in the mould former in the investing stage of casting in the production of metal RPD's
Holds investment steady
280
When would a ring not be needed in the mould former in the investing stage of casting in the production of metal RPD's
If the investment is phosphate bonded
281
How long do you wait after setting the mould until you place it in the furnace in casting in the production of metal RPD's
1 hour
282
What is the temperature rise + time taken for it at the start of the furnace stage of casting in the production of metal RPD's
0-1100C | in 3-3.5 hours
283
What is the cobalt chromium melting point
1400C
284
How long is the mould held at the precasting temperature in the furnace stage of casting in the production of metal RPD's
30 minutes
285
Why is a heat soak done in the furnace stage of casting in the production of metal RPD's
Ensures even thin sections are hot
286
What 2 things happen if the heat soak is not done in the furnace stage of casting in the production of metal RPD's
Metal freezes on contact meaning the mould will not fill fully Mould expands + cracks
287
What do youWhat 2 things do you do in the furnace stage of casting in the production of metal RPD's
Heat the cast | Pour molten metal into cone
288
What should you follow when cooling in the casting in the production of metal RPD's
Follow manufacture guidelines
289
How is the cooled mould removed from the metal in casting in the production of metal RPD's
Tap residue of casting button
290
How do you clean the casting in in the production of metal RPD's
In a sandblasting cabinet with aluminium oxide
291
3 things to do after the cast has been produced in the production of metal RPD's
Inspect cast Fit to dental cast Electropolish
292
What is a common case of air bubble on the surface of a cast in the production of metal RPD's
Wrong mixing time of refractory cast
293
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BDS2 (3 decks)

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