prosthodontics Flashcards
(142 cards)
1
Q
effects of edentulism - 4
A
loss of masticatory function
self esteem
poorer quality of life
speech
2
Q
cawood and Howell ridge resorption classifications
A
1 = before extraction
2 = immediately after extraction
3 = high well rounded ridge
4 = knife edge ridge
5 = low well rounded ridge
6 = depressed ridge
3
Q
why is a parkinsons pt not suitable for dentures
A
dentures require good neuromuscular control
4
Q
what compromises stability of lower denture
A
tongue movements
5
Q
reasons to render a pt edentulous - 5
A
advanced perio/ hopeless teeth
rampant caries
severe and debilitating tooth wear
pre surgery - infection risk
pre chemotherapy - infection risk
6
Q
4 reasons older people get caries
A
xerostomia
sjogrens syndrome
dementia
radiation caries
7
Q
3 methods of complete denture construction
A
conventional
digital
replica
8
Q
when would you make a conventional denture
A
no previous denture or previous denture unsuccessful
9
Q
how would you modify a stock tray
A
green stick wax
soft red wax
putty
reduce with acrylic bur on straight hand piece
10
Q
good impression material to use for retching pt
A
red composition
11
Q
3 things to assess edentulous impression for
A
are all edentulous areas included
are sulcus areas included in denture recorded fully
are there any deficiencies - air blows
12
Q
spacing for special tray when impression will be taken with alginate/heavy bodied elastomers
A
3mm
13
Q
spacing for special tray when impression will be taken with light bodied elastomers
A
no spacing
14
Q
advantages of taking a master impression - 3
A
accurate peripheral extension
records denture bearing area accurately
reduced material - more comfortable
15
Q
aims when taking master impression - 3
A
all relevant areas recorded
no air blows
well rounded borders
16
Q
information to gather when taking denture history - 3
A
age of denture
how many sets
success?
17
Q
dental history for complete denture questions - 3
A
why teeth loss
when teeth lose
any retained roots, pain or swelling
18
Q
what medical problems influence patient suitability for denture
A
neuromuscular problems
parkinsons
stroke
dementia
dry mouth
sjogrens
19
Q
define support of a denture
A
resistance of vertical movement of a denture towards ridge
20
Q
primary and secondary support area of upper compete
A
primary - hard palate
secondary -ridge crest
21
Q
primary and secondary support areas of lower complete denture
A
primary - buccal shelf and retromolar pad
secondary - ridge crest
22
Q
what is ICP
A
complete intercuspation of opposing teeth independent of condylar position
23
Q
what is RCP
A
guided occlusal relationship occurring at most retruded position of condyles in joint cavity - most reproducible
24
Q
define stability of denture
A
ability of denture to resist displacement by functional stresses in a horizontal direction
25
define retention of denture
the resistance to vertical displacement of denture away from tissues
26
define adaptation of denture
degree of fit between a prosthesis and supporting structures
27
clinical and lab stages of replica denture - 8
replica mould of old denture
lab makes replica block
master impression and bite registration
cast impressions and mount casts and set up
try in
process and finish dentures
delivery/insertion
review
28
denture try in checks
Lip support
appearance
even contact in RCP
speech
retention and stability
base extensions
lower teeth over ridge
29
denture insertion checks
appearance
even contact in RCP
speech
retention and stability
base extensions
comfort
30
denture review checks
pain redness ulcers
function
aesthetics
speech
OVD
31
mucocompressive impression meaning
pressure is applied and shape of tissue under load is recorded
32
mucostasis impression meaning
minimum pressure applied and tissue shape at rest is recorded
33
how could you alter impression technique for flabby ridge
use perforated tray over ridge
alginate in non-flabby area - mucocompressive
light bodied silicone on flabby area - mucostatic
34
conventional clinical and lab stages - 10
primary impressions
primary casts and special trays
master impression
master casts and record blocks
jaw registration
mount casts and set up teeth
try in
process and finish
insertion
review
35
when would you chose a close fitting tray oner 3mm spaced tray
resorbed ridges
36
steps of jaw reg - 7
adjust upper for retention
adjust upper for tooth position
adjust upper for occlusal plane
lower tooth position and horizontal jaw relationship
OVD
record registration
shade mould and setting
37
what does LIMBO stand for and when do you use this
Lip support
Incisal Level
Midline and canine lines
Buccal corridor
Occlusal plane
use when adjusting record block for complete conventional denture
38
recommended nasiolabial angle and edentulous nasiolabial angle
90
96 in edentulous
39
what reference do you use to check anterior occlusal plane
interpupillary line
40
reference for posterior occlusal plane
ala tragus line
41
what is the neutral zone
space between the lips and cheeks one one side and the tongue on the other - area where forces between tongue and cheeks/lips are equal
42
OVD definition
distance between set point on maxilla and set point on mandible when teeth/denture are in maximal intercuspation
43
RVD definition
when mandible is at rest, distance between point on mandible and point on maxilla
44
what can affect RVD measurement
stress
pain
anxiety
tense up facial muscles
45
what are the effects of excessive freeway space - 3
reduced masticatory efficiency
overclosed appearance
TMJ pain
46
effects of reduced FWS - 3
excessive load on denture bearing area
continuous muscle activity - pain
noisy dentures
47
normal FWS
2-4mm
48
what articulator requires face bow
semi adjustable
49
materials used for artificial teeth - 3
porcelain
composite resin
acrylic
50
what do the numbers mean on mould guide top to Botton
mould
width of 6 ant teeth flat
width of L central
height of L central
51
factors influencing shade and shape selection
pt opinion
photographs
old dentures
existing teeth or partials
52
what factors influence posterior teeth choice - 2
ridge width
neuromuscular control
53
when would you consider cusp less teeth
when it is difficult to get reproducible jaw relationship
54
before the patient arrives for a try in, what do you check the lab work for
correct patient
correct prescription
correct mould and shade
special instructions adhered to
damage?
55
complete denture try in check list
retention and stability
base extensions
LIMBO
position of teeth
FWS
even contact in RCP
speech
aesthetics
56
how would you test pt speech with denture
fricatives
count 60-70
days of week
57
s sound when testing speech
too much FWS or too class 2 as too much air escaping
correct by adjusting ant tooth position or increasing OVD
58
teeth contact during speech
reduce OVD and insufficient FWS
59
what can you use to aid detection of areas causing discomfort from new denture
pressure indicating paste
60
denture hygiene advice - 5
brush dentures daily - non abrasive
rinse after meal
soak dentures daily - 20 mins with alkaline peroxide or hypochlorite - 10 mins if metal - rinse then soak over night in cold water
leave dentures out at night
visit dentist regularly
61
reasons poor denture hygiene - 4
poor manual dexterity
xerostomia
wearing dentures full time
lack of knowledge
62
what forms the pellicle layer
salivary proteins and bacterial. products
63
fusobacteria produces sulphur products, what is the effect of this on oral cavity
halitosis
64
why do fungal spices adhere to dentures
candida has affinity for PMMA
acidic environment under denture favours candida activity
65
why does debris accumulate on denture
denture surface not smooth
decreased salivary flow in elderly
fit surface nor exposed to cleaning effects of saliva
66
what are the effects of poor denture hygiene - 4
caries
halitosis
denture stomatitis
periodontal disease
67
most common mechanism for pneumonia in elderly
respiration of food, reflux and oral bacteria into lower respiratory tract
68
how do dentures impact aspiration pneumonia
dentures act as reservoir for potential respiratory pathogens thus increasing risk of aspiration pneumonia
69
3 ways to mechanically clean denture
soap and soft brush - toothpaste and not soft will scratch acrylic
microwave for 20 secs
ultrasonics
70
chemical denture cleaners - 2
alkaline peroxide
alkaline hypochlorite - not for soft lining
acids - not for metal or soft linings
71
what health benefits are there of removing dentures and soaking them over night
prevents stomatitis and aspiration pneumonia
72
advantages of immediate denture -4
self esteem
function
post extraction healing
avoid drifting of teeth
73
disadvantages of immediate denture
poor fit stock tray
74
contraindications of immediate denture
MRONJ
dementia
pre chemo / pre radio
75
when is rate of resorption most rapid
first 6 months
76
steps of immediate denture to replace one or two anterior teeth that have been affected by trauma or tooth fracture
impressions U and L
intra occlusal record
choose shade
prescription to library with design and teeth gonna be extracted
extraction and insertion same day
77
4 displacing forces that affect denture
gravity
muscle activity
function
sticky foods
78
define adhesion - give 2 examples
physical attraction of unlike molecules for each other
saliva and mucous membrane
saliva and denture base
79
define cohesion
physical attraction between like molecules
e.g. saliva film
80
what is atmospheric pressure important for in dentures
border seal
81
3 necessary aspects of denture fitting surface
full coverage of denture bearing area
good adaptation to mucosa
adequate post dam seal maxilla
adequate extension into lingual pouch
82
another name for retromylohyoid fossa
lingual pouch
83
5 factors that make retention and stability difficult
atrophic ridges
congenital cleft
fibrous ridge
gagging - can't tolerate base extension
CoCr adapts less well than acrylic
84
aids to denture adhesion and stability - 2
denture adhesives
linings
implants
85
what directly impacts adaptation of denture
good impression
86
why is it important to relieve the incisive papilla
compression of nasopalatine nerve and vessels by denture
leads to necrosis of areas supplied and paraesthesia of anterior palate
87
what is a relief area
denture should be designed so masticatory load is relieved from these areas as these areas can be easily traumatised e.g. thin mucosa or fragile underlying structures or resorption under constant load
88
what is the lingual frenum
fibrous band covered in mucosa
important not to be covered by denture as will cause pain and instability
denture must extend adequately around though without encroaching to ensure peripheral seal
89
relief areas for upper denture
incisive papilla
90
3 limiting structures for upper denture
buccal sulcus
labial sulcus
lingual and buccal frenum
91
relief areas of lower denture - 2
mylohyoid ridge
92
support areas of lower denture
primary - buccal shelf and retromolar pad
secondary - residual alveolar ridge
93
3 limiting structures of lower denture
retromolar pads
buccal and labial and lingual frenum
buccal and labial sulcus
94
4 objectives of complete dentures
adequate masticatory function
restore natural appearance
restore normal speech
comfort and preservation of supporting structure
95
4 objectives of complete dentures
adequate masticatory function
restore natural appearance
restore normal speech
comfort and preservation of supporting structure
96
4 factors affecting retention of complete dentures and give examples of each
physical - adhesion, cohesion, atmospheric pressure, gravity
anatomical - shape of edentulous area, undercuts
physiological - neuromuscular control, saliva viscosity and volume
mechanical - balanced occlusion, position of teeth to ridge and occlusal plane
97
what is atmospheric pressure
hydrostatic pressure due to weight of atmosphere on earths surface
98
where should teeth be positioned in respect to lower ridge - 2
directly above lower residual alveolar ridge
within neutral zone
99
what should the horizontal distance be between the probe on the incisive papilla and and the probe against the incisor edge of the incisor edge of maxillary central incisors be?
1cm
100
height and width of lower record block
18mm height
10mm width
2/3 of retromolar pad height
101
height and width of upper record block
H ant. 22mm
H post. 18mm
W ant 5-7mm
w Post. 10mm
102
anatomical landmark to use to mark centre line
distal of incisive papilla - 10mm to labial surface of incisor
103
alma gauge use
determines the vertical and horizontal position of anterior teeth relative to a point on the denture base (e.g. incisive papilla).
104
types of indirect restorations
veneers
inlays/onlays
crowns
post and core
bridge
105
why place a veneer - 4
improve aesthetics
change tooth shape/colour
correct peg shape laterals
reduce/close diastema
106
4 contraindications to venners
poor OH
high caries
gingival recession
heavy occlusal contacts
107
onlay/inlay indications - 3
tooth wear
fractured cusps
restoration of RCT
108
when to use crowns - 3
to protect weak tooth
improve aesthetics
retainer for bridgework
109
contraindications to crown - 3
more conservative option availible
active caries/periodontal disease
lack of tooth tissue for prep
110
what are the 6 principles of crown prep
preservation of tooth structure
retention and resistance
structural disability
marginal integrity
preservation of periodontist
aesthetic considerations
111
why preserve tooth structure - 2
prevent unnecessary weakening of tooth
protect pulp
112
result of over prep for crown
pulp and tooth strength compromised
113
underprop of crown result
poor aesthetics
overbuild crown
insufficient thickness of crown
114
meaning of retention of crown
prevents displacement of crown along long axis of tooth prep
115
meaning of resistance of crown
prevents dislodgement of crown by forces on crown including occlusal
116
ideal taper of walls of crown
6-10
117
what property does limiting the number of paths of insertion of a crown improve
retention
118
how do you give structural durability to a crown
functional cusp bevel
occlusal reduction
axial reduction
119
how do you ensure periodontist is preserved when placing a crown - 3
margins smooth and fully exposed to cleaning
placed where dentist can finish them and patient can clean them
placed supra gingival or at gingival margin if possible
120
what is an indirect restoration
restoration fabricated outside mouth by technician in lab
121
what is an inlay
intracoronal restoration made in lab
122
3 materials used for inlay and onlay
composite
gold
porcelain
123
indications for an inlay - 2
premolar or molar
occlusal restoration
124
what advantages do inlays have over direct restorations
superior materials and margin
won't deteriorate over time
125
ceramic inlay prep - isthmus and margin
1.5-2mm isthmus
shoulder or chamfer 1mm
126
gold inlay prep
1mm isthmus
0.5 chamfer margin
127
what is an onlay
extra coronal restoration made in lab - like inlays but with cusp coverage - require cuspel reduction
128
indications for onlay
sufficient occlusal tooth substance loss
remaining tooth surface weak - caries
129
what margin design is used for onlay or inlay
porcelain 1mm shoulder or chamfer
gold 0.5mm chamfer
130
alternative to inlay/onlay - 2
large direct restoration
crown
extraction
131
materials for veneer
ceramic
composite
gold
132
4 intrinsic causes of enamel discolouration
tetracycline
fluorosis
ageing
non vital teeth
133
labial reduction and incisor reduction for veneer
0.3 cervical - 0.5 labial mid
1-1.5 incisal
134
alternative option for temporary veneer
spot bonded composite - no etch, use bond only and apply composite
135
alternatives for veneer restoration
no treatment
microabrasion
ICON - penetrative resin restorations
crowns
136
material for provisional restoration
chemically cured bis acrylic composite
pro temp
137
materials for preformed provisional crown
polycarbonate
clear plastic
metal - SS
138
problems with preformed crown
unlikely to fit accurately
large bank of crowns are needed - costly
139
when are preformed crowns useful
when no impression is taken prior to tooth prep or damage
140
what do you use to cement temporary crown
temporary luting cement e.g. temp bond
141
advantages of indirect provisional restorations
accurate
low shrinkage
high strength
142
indirect provisional restorations material - 3
composite
acrylic - common
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