RPD HOLY GRAIL Flashcards
1
Q
Which of the following are done last?
A) Framework try in
B) Create rests
C) CR Record
D) Altered cast
A
D) Altered casts; assure support for RPD
2
Q
List the order of the following:
- CR Record
- Framework try in
- Altered cast
- Create rests
A
- Framework try in
- Create rests
- CR Record
- Altered cast
3
Q
If an RPD is part of planned treatment; plan the RPD:
A
Before beginning any other treatment
4
Q
These are the clinical steps for an RPD fabrication
1. Diagnosis, treatment plan, hygiene
2. Diagnostic casts
3. Draw design & list abutment modifications on the prosthesis design page
4. Instructor approval
5. Complete Phase I treatment
6. Abutment modifications
7. Preliminary impression to check abutment modifications
8. Fabricate and cement crowns or fixed partial dentures
9. Final framework impression
10. Make two casts
11. Draw design on 2nd cast
12. Instructor approval/ corrections of drawing/design on cast
13. Complete RPD framework prescription (instructor signature required)
14. Second pour cast with design sent to lab with first pour
15. Inspect wax-up
16. Framework adjustments (create rests)
17. Altered cast impressions if needed
18. Jaw relation records (CR record)
19. Select & set denture teeth
20. Try-in with teeth in wax
21. Process, adjustment, deliver to patient (altered cast)
A
5
Q
How far distally should the denture base extend in a class 1 distal extension case?
A
2/3 of the retromolar pad
6
Q
Bilateral edentulous area posterior to remaining teeth describes:
A
Kennedy Class I
7
Q
Maxillary framework extends (in Kennedy class I)
A
2/3 distance to hamular notch (resin engages further)
8
Q
How far distally should the retention extend for a distal extension case?
A
Extends to 2/3 from the guide plate to 2/3 of the retromolar pad
9
Q
Which of the following is the hardest to obtain with a distal extension case?
A
VDO record (possibly also establishing plane of occlusion)
10
Q
Essential to prevent displacement or deformation of the metal framework during resin-packing procedures
A
cast stop
11
Q
Cast stops project from the tissue surface of the ____ to contact the ___
A
minor connector; dental cast
12
Q
A ____ should be used to join acrylic resin and metal components at the internal surface of an RPD
A
butt joint
13
Q
A butt joint should be used to join ____ an d____ components at the ____ surface of an RPD
A
acrylic resin; metal components; internal
14
Q
Each internal finish line of a butt joint should display an angle of:
A
90 degrees
15
Q
The internal angles of external finish lines should be:
A
sightly less than 90 degrees
16
Q
The internal angles of external finish lines should be slightly less than 90 degrees, what does this result in?
A
improved mechanical retention for acrylic resin components
17
Q
In a butt joint the internal angle = ____; the external angle = ____
A
internal= 90
external= acute
18
Q
Base plate wax on cast for relief in edentulous areas:
A
wax patterns
19
Q
Wax patterns are made on the:
A
refractory cast
20
Q
The cast that is used for fabricating the framework:
A
refractory cast
21
Q
What does “support” mean for direct retainers?
A
resists vertical movement towards the soft tissue
22
Q
Resistance to removal from the tissues or teeth:
A
retention
23
Q
Resistance to movement in a horizontal direction (anterior-posteriorly or medio-laterally)
A
Stability
24
Q
Resistance to movement towards the tissues or teeth:
A
Support
25
A tooth that supports a partial denture:
abutment
26
A component of a partial denture that provides both retention and support for the partial denture:
retainer
27
What three components are required clasp assembly?
support, resistance & retention
28
T/F: The completed RPD must be passive
true
29
T/F: The RPD should exert forces on the teeth and soft tissue
false- the RPD should NOT exert forces on the teeth or soft tissue
30
T/F: The toe of each retentive clasp should lie passively in a measured undercut
false- The tip of each retentive clasp should lie passively in a measured undercut
31
Where should the tip of each restive clasp lie?
passively in a measured undercut
32
Clasps should be ____ when fully seated, meaning:
passive; not directing force on the tooth
33
The reciprocal arm of the clasp should contact the tooth:
before the retentive tip passes the height of contour
34
The reciprocal arm of the clasp should contact the tooth before the retentive tip passes the height of contour so it can:
hold the tooth in place as the retentive tip puts off-axis pressure on it
35
The reciprocal arm of the clasp should contact the tooth before the retentive tip passes the height of contour so it can hold the tooth in place as the retentive tip puts off-axis pressure on it. This:
neutralizes the stress from the retentive tip
36
T/F: A class I lever is ideal. RPI is an example of a class I lever.
False; false
37
Class I Lever=
most detrimental
38
Class II lever=
ideal- RPI is an example of a class II lever
39
RPI is an example of a:
class II lever
40
RPI stands for:
Rest (mesial), Proximal plate, I-bar
41
What type of support allows for an RPI?
Tooth tissue (class I, II, & long class IV)
42
Does an RPI satisfy the principle of encirclement?
NO
43
RPI= class II lever =
stress release
44
Wrought wire needs an elongation factor of:
more than 6%
45
It is important that a wrought wire clasp have an elongation percentage of more than 6% (PTQ) allowing _____ without microstructure hangers that could compromise its physical properties (like creating a fracture)
allowing clasp to bend
46
Check biting is caused by:
a) lack of horizontal overlap
b) Mandibular teeth too far buccal
47
Moving the buccal cusp lingually increases
horizontal overlap
48
Caused by insufficient overlap between maxillary and mandibular teeth:
cheek biting
49
If artificial teeth are correctly positioned and cheek biting occurs:
round the buccal cusps of mandibular posterior teeth to move buccal cusps slightly lingually (thereby creating a greater horizontal overlap)
50
If cheek biting occurs and artificial teeth are incorrectly positioned or rounding does not help:
remove the artificial teeth and reset them
51
Caused by the artificial teeth being positioned too far lingually, resulting in a decrease in tongue space:
tongue biting
52
Tongue biting is caused by the artificial teeth being positioned too far _____, resulting in a ____ of tongue space
lingually; decrease
53
How do you fix tongue biting?
by rounding lingual cusps/recontour lingual surface
54
What would the following alterations help?
- gentle "rounding or rolling" of lingual cusps and recontouring of the lingual surfaces of the mandibular teeth
tongue biting
55
What do you do if tongue biting continues after teeth have been reshaped?
Remove and reset artificial teeth
56
Which of the following doesn't call for a rebase?
dentition or moveable
57
_____ is a laboratory technique in which the bulk of the denture base is removed and replaced using new resin
rebasing
58
The rebasing approach results in a ______, but is technically complicated by the fact that the retentive meshwork is buried within the denture base- often without sufficient relief beneath the mesh to allow for adequate bulk of new resin
base of uniform quality
59
Rebasing is indicated when: (3)
1. denture bases do not extend to cover all of the denture bearing tissues
2. denture base has been fractured
3. denture base has become irreparably discolored
60
1. denture bases do not extend to cover all of the denture bearing tissues
2. denture base has been fractured
3. denture base has become irreparably discolored
What would you do for the listed situations?
rebase
61
_____ when both denture base and denture teeth need work
____ when atleast 2mm is present under denture base OR indirect retainer lifts 2mm+
Remake; Reline
62
When should you reline the denture base?
1. when atleast 2mm is present under denture base
2. when indirect retainer lifts 2mm+
63
The anterior teeth disclude the posterior teeth when the mandible moves in protrusion:
anterior guidance
64
Anterior guidance describes the anterior teeth disclude the posterior teeth when the:
mandible moves in protrusion
65
With anterior guidance, the ____ , ____, and ____ disclude the posterior teeth when the mandible moves in protrusion
canines; central incisors; lateral incisors
66
With anterior guidance, the canines, central incisors, and lateral incisors disclude the posterior teeth when the mandible moves in:
protrusion
67
Contacts between the posterior teeth during excursive movements are considered ____ that can create damaging effects on the teeth and periodotnium.
interferences
68
With anterior guidance, describe what should occur with the posterior teeth:
Posterior teeth SHOULD NOT touch (in excursive movements)
69
These create off-axis forces in posterior teeth, where you're close to the TMJ. Meaning high load in off-axis direction, leading to damage to the teeth
Interferences (posterior teeth)
70
Which of the following are involved in support?
A) Rest
B) Major connector
C) Denture base
D) All of the above
D) All of the above
71
What material is most commonly used to make denture bases?
PMMA
72
What denture base material is being described?
- Difficult to adjust
- Poor esthetics
- Part of cast framework
- Good thermal conductivity
- Can be kept thin
Metal
73
What denture base material is being described?
- Acrylic resin
- Most common
- Easily adjusted and relined
- Good esthetics
- Attached to framework by lattice or mesh
Polymethyl methacrylate (PMMA)
74
_____ is the most common material used for a denture base
PMMA
75
What type of material should be used in distal extension cases?
PMMA
76
What type of joint should be used with PMMA?
Butt joint (90 degrees) with major and minor connector
77
Can you reline a PMMA base?
yes
78
Advantages of acrylic resin bases (PMMA) (3):
1. ability to reline the base as the supporting tissue changes
2. Esthetically superior to metal bases
3. Ease of repair
79
Disadvantages of acrylic resin bases (PMMA) (4):
1. Dimensional stability less than metal base- warpage
2. Lower strength than metal- long spans
3. Porous- hygiene
4. Low thermal conductivity
80
What occurs if instead of a butt joint (90 degrees) for acrylic resin bases, a feathered edge is used?
distortion, breakage, or separation from the framework causing injury to the underlying soft tissue
81
Which of the following is true about PIP? For the false options make them true!
A) PIP means pink indicating paste
B) Should be put on camio surfaces
C) Should be put in great amounts
D) Should be in brush strokes
True: D- should be in brush strokes
A- PIP means pressure indicating paste
B- Should be put on intaglio surface
C- Should be put in small amounts
82
Checks soft tissue impingement during framework adjustment step:
PIP
83
PIP is placed on the ____ surface to check for ____ areas
intaglio; pressure
84
If clasps are tight on a class III with circumferential clasp you use what to adjust?
A) 139
B) Hemostat
C) 200
D) Remake
A- 139
85
A class III is ___ supported
tooth
86
Indications for circlet:
undercut OPPOSITE of edentulous site
87
An undercut adjacent to the edentulous site means NO:
circlet
88
For adjusting retentive clasps as a general rule, at the time of insertions ____ retention should be used
slightly less than maximum
89
Only the ____ should be used when adjusting a half round cast circumferential cast
139 plier
90
Only the 139 plier should be used when adjusting:
half round cast circumferential clasp
91
Clasps should be adjusted in:
small increments
92
Excessive bending of a clasp in one direction only will lead to:
accelerated fatigue and failure of the clasp
93
The surveyor is used for:
a) undercuts
b) interferences
c) path of draw
d) all of the above
d) all of the above
94
If there isn't a lot of inter arch space, what material should be used for the denture base?
metal
95
Metal bases cannot be relined so they are generally not used for:
tooth-tissue borne removable RPDs or in areas where teeth has been removed in 12 months
96
Why are metal bases not used for teeth that have removed within 12 months?
resorption will still be occurring at an increased rate, and relining will usually be required
97
T/F: All distal extension cases require clinical remount. All class 3 might require clinical remount
first true; second false
98
All ____ cases require a clinical remount
distal extension
99
All ____ supported RPDs will require clinical remounting
tooth-tissue
100
Which of the following will require a remount?
a) class III tooth supported
b) class I tissue supported
c) Class II tissue supported
B & C
101
Chromium-cobalt shrinks:
2.2-2.4 %
102
What metal is used at UMKC?
CoCr
103
Why is CoCr used more than NiCr?
due to nickel allergy
104
Possible causes of failure of chromium-cobalt alloys include:
1. cold-working
2. shrinkage-porosity
3. low percent elongation
4. excessive carbon in the allow
105
Cause of chromium-cobalt failure that reduces the percentage of elongation that causes a decrease in hardness:
Cold working
106
Cause of chromium-cobalt failure due to the alloys shrinking approximately 2.3% resulting in porosity
shrinkage porosity
107
Cause of chromium-cobalt failure directly related to greater brittleness
low percentage elongation
108
Cause of chromium-cobalt failure that involves reactions with other constituents to form carbides:
excessive carbon in the alloy
109
which occurs last?
A- altered cast technique
B- CR record
C- Framework made
D- Rest created
A- Altered cast technique
110
Put the following in order:
- create rests
- framework try-in
- altered casts
- CR record
1. framework try in
2. create rests
3. CR record
4. altered cast
111
What is the purpose of an altered cast impression?
To capture an accurate relation between the teeth, framework, and residual ridge (in distal extension cases)
112
What do you need a clinical remount?
interocclusal record (jaw relation)
113
Clinical remounting procedure:
1. face bow preservation
2. pickup impression
3. block out undercuts
4. remount cast and interocclusal record
5. articulate
114
Describe a pick up impression:
When you insert the RPD in the mouth, then take an impression so that the impression pick ups the RPD plus shows where the teeth are
115
Which of the following is NOT an advantage of chromium-cobalt alloys?
A- low density (weight)
B- high modulus of elasticity (stiffness)
C- low material cost
D- resistance to tarnish
E- increased flexibility
E- increased flexibility (we want rigid; not flexible)
116
Necessary to ensure that the partial denture functions as one unit:
rigidity
117
If the denture flexes, ____ & ____ can be compromised
cross arch stabilization and stress distribution
118
A major connector can be made more rigid by:
using a more rigid alloy (CrCo)
119
Chromium cobalt alloys are ___ in comparisons to gold or palladium alloys
more rigid
120
Chromium cobalt alloy stiffness can be overcome by including:
wrought-wire retentive elements in there framework
121
_____ alloys are approximately twice as flexible as the ____ alloys
gold alloys; chromium cobalt alloys (PTQ)
122
Kellys Combination syndrome would present as:
Lack of osseous tissue in the anterior maxillary
123
What does NOT describe Kelly's combination syndrome:
- Lack of osseous tissue in the anterior maxilla
- Loose tissue in the posterior maxilla
- Intrusion of the mandibular anteriors
- cystic palatine nerve
Loose tissue in the posterior maxilla
124
T/F: Guide plane should be 1/2 distance between cusp tips. Guide plane is as wide as rest.
Both true
125
How wide should the guide plane be?
- as wide as the widest portion of the occlusal rest
- 1/3 the BL width of the tooth
- 1/2 distance between cusp tips
126
With a guide plane, the normal tooth contour is maintained:
buccolingually
127
T/F: The gingival margin to superior border of lingual bar is 3-4 mm. Measure the distance on the cast, not in the mouth.
First statement true; second statement false. Measure the gingival margin to superior border of lingual bar in the mouth
128
Beaded border depth:
1mm deep; 1.5mm wide
129
a prepared groove on the master cast along the designated borders of maxillary major connectors:
bead
130
What is the purpose of a bead?
1. increased rigidity
2. guide for finishing
3. compensate for casting inaccuracies
4. displaces soft tissue, prevent food/air/fluid collection
131
What is the primary action of a bead?
displaces soft tissue, preventing food/air/fluid collection
132
Describe the dimensions of a beaded border:
using 1/2 round bur, 1 mm deep and 1.5 mm wide; feathers out to nothing 6mm from the free gingival margin; shallower over the mid palatal suture
133
If you have a large inoperable torus you need to use:
horseshoe
134
If you have a very high palatal vault you need to use:
horseshoe
135
I-bar with distal extension does NOT use:
DF undercut (it does use MF and mid-f)
136
Papillary hyperplasia is all except:
destructive bone disease
137
Papillary hyperplasia is a form of:
denture stomatitis
138
Where is papillary hyperplasia found at?
palatal vault
139
Causes of papillary hyperplasia include:
1. local irritation
2. poor fitting dentures
3. poor oral hygiene
4. leaving denture in 24 hrs a day
140
Treatment for papillary hyperplasia includes:
1. educate patient on oral hygiene
2. advise patient to leave denture out at night
3. soak denture for 30 min in 1% sodium hypochlorite & rinse thoroughly
4. use tissue conditioner
5. patient should brush irritated area lightly with a soft brush
141
T/F: A cingulum rest is placed between the incisal and middle one third of incisors
False- its near the cervical end for maxillary anterior teeth
142
Indications for lingual rest seats include:
1. primarily maxillary canines- not incisors
2. canines with gradual lingual slope
143
____ transmits the forces along the long-axis of the tooth; prevents migration
Postive rest seat
144
A positive rest for a cingulum rest is used because:
it prevents lateral movement
145
A positive rest for a cingulum rest directs forces:
toward long axis of tooth
146
A surveyed crown is indicated when:
a- the survey line is in the gingival 1/3
b- no undercuts exist on abutment teeth
c- with the help of enamels-last, one cannot have the changes necessary for the abutment teeth without cutting into dentin
d- all of the above are true
all of the above are true
147
Indirect retainers have all of the following characteristics except:
Its a DO rest on a posterior abutment (Want as far forward as possible so use an MO)
148
Hyuperplastic tissue should be removed prior to construction of your RPD to:
provide a firm, stable base for the denture
149
Before construction of a CD or RPD, it is very important to:
surgically remove the hyperplastic tissue
150
The best impression technique for a patient with loose hyperplastic tissue is to:
register the tissue in its passive position (PTQ)
151
