308 - support during stages of prosthetic treatments. Flashcards
what is prosthodontics?
restoration or replacement of damaged or missing teeth using artificially constructed devices
what can missing teeth be replaced by?
dentures
implants
bridges
who creates fixed or removable prosthesis?
dental technician
what is an opposing arch?
the arch that doesn’t contain tooth to be resotred/replaced
what does edentulous mean?
no teeth present
what material is irreversible hydrocolloids?
alginate
what material is addtion siliciones and vinyl polysiloxanes?
elastomer
(heavy bodied putty - light bodied paste)
what material is polyether?
elastomer
what is alginate used for?
opposing arch
models for full/partial denture
models for removable ortho appliances
study models
models for special trays, bleachign trays, retainers
can alginate be used for the working model for crowns/bridges/veneers/inlays?
NO
what temperature should water be to mix alginate?
room temperature
what proportion is needed to mix alginate?
1:1
powder to water
what does alginate mix need to be free of?
air bubbles
what should alginate be wrapped in if it can’t be casted immediately?
damp gauze and sealed in airtight bag
what happens to alginate if it is left immersed in water?
impression expands
what happens to alginate if it is allowed to dry out?
impression shrinks
what is addition silicone elastomer used for?
fixed prosthetic work as it is highly accurate
what is the setting time for silicones?
4 minutes
what are the advantages of silicone elastomer material?
dimensionally stable in presence of moisture
excellent elasticity, strength and accuracy
what are the disadvantages of silicone elastomer material?
more complicated/time consuming than alginate
more expensive
longer setting time - uncomfortable for patient
what are polyethers used for?
fixed prosthetic work and some removable prosthetic work
what is the correct disinfection technique of impressions?
run under cold water to remove visible debris
immersed into disinfectant bath (10 MIN)
rinsed under cold water again
what is the solution for disinfecting impressions?
10% sodium hypochlorite
how long should impressions be immersed in the disinfectant bath?
up to 10 minutes
what to do with alginate impressions after disinfection?
cover with wet gauze and seal in airtight bag
what to do with elastomer impressions after disinfection?
blow dry with 3 in 1 syringe and seal in airtight bag
what does a working lab ticket need to include?
dentist
patient name
prosthesis to be constructed
material to use
shade
date of delivery for fit
disinfection details
what is an impression tray made by the technician called?
special tray
what is a special tray?
custom made and individual to patient
what does a triple tray record?
partial section of both arches and occlusion
what is a fixed prosthesis?
restorations or replacements cemented within or onto a tooth
what is a crown?
a cap covering 3/4 to whole surface of a tooth
what is a bridge?
two or more crown like units joined together as single device to replace missing tooth
what is a veneer?
facing made to fully cover labial surface of tooth
what is an inlay?
insert into tooth cavity
what is the purpose of a crown?
protect heavily filled or root filled tooth from fracturing
aesthetics
tooth shape change
what material can crowns be?
porcelain ceramic
all ceramic
precious metal alloy
non-precious metal alloy
what is the purpose of a bridge?
replace missing teeth
aesthetics
what material can bridges be?
all ceramic
bonded porcelain to metal
precious metal alloy
non-precious metal alloy
what is the purpose of a veneer?
aesthetics
what material can a veneer be?
porcelain
what is the purpose of an inlay?
restore cavity with material stronger than conventional filling material
what material can an inlay be?
all ceramic
precious metal alloy
non-precious metal alloy
what burs are used during a crown prep?
diamond tapered burs
what do diamond tapered burs do?
produce near-parallel sides for retention without undercuts
what is the use of a gingival retraction cord?
for accurate recordings of crown prep margins
what is a crown cemented with?
luting cement
what are the type of luting cements for crowns?
self-cure resin
light-cure resin
dual-cure resin
polyester resin
glass ionomer
zinc polycarboxylate
zinc phosphate
what is a porcelain jacket crown?
all-procelain crown for anterior teeth only
what is an all-ceramic crown?
stronger ceramic material
require less tooth removal
e.g. emax
what is a porcelain bonded crown?
substructure of metal for strength
buccal/labial face of porcelain for aesthetics
what is a full gold crown?
strongest crown
ideal for posterior teeth
not aesthetic
what is a post crown?
metallic post and core structure shaped to hold conventional crown
what type of post is screwed into the canal?
dentatus system
what type of post is cemented into the canal?
parapost system
compositpost system
why are temporary crowns used?
maintain appearance
prevent sensitivity of prepared teeth
maintain correct space between adjacent teeth
maintain correct occlusion
what is the hall technique?
cementation of preformed metal crown onto carious deciduous molar tooth
what is a pontic?
unit replacing missing tooth
what is a bridge retainer?
unit holding bridge in place
what is an abutment?
tooth bridge is cemented on to
advantage of bridges over dentures?
no embarrassment of loose prosthesis falling out
more hygienic than dentures
only 2 appointments required to make bridge
solve problem of gag reflex
what is a fixed-fixed bridge?
retaining teeth involved to either side of missing teeth
fixed-moveable bridge?
joint is incorporated in design to allow some degree of flexibility to the bridge
what is a cantilever bridge?
retaining tooth or teeth to one side of pontic only
what is a simple cantilever design?
retaining teeth immediately to one side of the pontic only
what is a spring cantilever design?
retaining teeth are to one side but several teeth away from pontic
what is an adhesive bridge?
retaining teeth undergo minimal tooth preparation and retention provided by lingual/palatal metal wings only
do you need a radiograph for a bridge?
yes - to check the health of tooth
what are the oral hygiene instructions for crowns and bridges?
regular toothbrushing daily
fluoride toothpaste
flossing/interdental brushing to clean interproximally
what material can veneers be?
composite or porcelain
what are veneers used for?
mask discoloured tooth
mask darkened root filled tooth
close diastemas
change shape of rotated teeth
what material can dentures be made of?
acrylic
chrome-cobalt metal
valplast
why may teeth be replaced by a removable prosthesis?
prevent excessive masticatory forces
prevent overeruption of opposing teeth
provide good aesthetics
what does acrylic material consist of?
powder called polymer
liquid called monomer
becomes dough consistency
how is acrylic cured?
heating dough slowly in special flask/oven
what is an alveoplasty?
chnaging shape of existing ridge by removal of gross under cuts
what is an alveolectomy?
surgical removal and smoothing of sharp ridges
what is a valplast denture?
denture that is flexible when placed in warm water then into the mouth
what are the denture stages?
1st - primary impressions with stock trays
2nd- special trays to take another impression (can do bite as well)
3rd - bite stage - wax rims, use willis bite gauge, bite reg paste
4th - try in - any changes?
5th - fit
what does a willis bite gauge measure?
occlusal face height of patient with edentulous arch
what materials are needed during the denture bite stage?
wax bite rims
wax knife
bite registration paste
pink sheet wax
willis bite gauge
heat source
work ticket
what instructions are given once denture is fitted?
how to insert/remove denture
don’t wear overnight - avoid oral fungal infections
store overnight in pot of water
clean after each meal
continue attending oral health assessments
how often do edentulous patients need to attend for oral health assessments?
ideally annually
if not
at least once very 2 years
what is denture stomatitis?
soft tissues covered by dentures become inflamed
what antifungal drugs treat denture stomatitis?
nystatin
fluconazole
what benefits have chrome-cobalt dentures got over acrylic?
thinner palatal covering
stronger
more hygienic
what should chrome-cobalt dentures be cleaned with?
non-hypochlorite as bleach can cause metal corrosion
what are immediate dentures?
immediate replacement denture when anterior teeth are extracted
what must the patient be made aware of after having an immediate denture made and fitted?
alveolar bone resorption will occur
prosthesis can become loose because of this
what procedures can be done to a denture to improve its fit?
relines or rebases
additions of teeth/clasps
replacement of worn teeth
what is a reline/rebase?
a new layer of acrylic after alveolar bone loss to fit better
what is a denture addition?
addition of a tooth or clasp to a denture
what are the tissue conditioners materials?
soft lining - when soft tissues under denture are sore
functional impression - material sets over hours and records soft tissues and denture extremities more accurately
what are obturators?
special removable prostheses provided to patient from a hospital dental department
seal off abnormal cavity in maxilla
e.g. cleft palate
what are overdentures?
full denture fitted over standing teeth or retained roots
what do orthodontic appliances do?
align crooked teeth
what types of orthodontic appliances are ther?
fixed appliance
removable appliance
what appliances move teeth forwards/backwards?
removable and fixed
what appliances move jaws in relation to each other?
functional and fixed
what appliances align slightly misplaced teeth?
removable and fixed
what appliances align severely misplaced teeth?
fixed only
what appliance for derotation of teeth?
fixed
what appliance for guided eruption of unerupted teeth?
fixed
what appliances for guided eruption of deep overbote?
removable and fixed
what is an archwire?
flexible wires to fasten into brackets or bands
what are end cutters?
right-angled cutters to trim ends of the archwire after replacement
what are alastiks?
rubber bands to hold archwire into slots of each bracket
what are alastik holders?
ratcheted holders to apply alastiks to the brackets
what are brackets?
metal/ceramic components attached to each tooth
what are bands?
metal rings to attach to molars
what is a buccal tube?
used instead of molar band where orthodontic forces are unlikely to dislodge tube
what are bracket holders?
hold and postion each bracket to centre of tooth
what are the bonding materials for orthodontic appliances?
acid etch
resin bond
what advice is given after having fixed appliances placed?
careful brushing
fluoridated toothpaste
interdental brushing
disclosing tablets
what are adams cribs?
retain appliance in mouth
fit onto molar or premolar
what are springs?
move teeth along arch as required
what are retractors?
push one/several teeth backwards
what are expansion screws?
move several teeth outwards
what advice is given to patients with removable appliances?
clean after each meal
wear at all times
avoid cariogenic and acidic foods/drinks
what are adam’s crib pliers?
adjust metal springs and retractors
what is an expansion screw key?
count number of turns to screw between visits
what is a functional appliance?
appliance made of acrylic and stainless steel worn in both arches at the same time
e.g. twinblock
what do functional appliances do?
correct skeletal class II discrepancies where mandible is further back from ideal position
what are aligners?
retainer-like appliance which achieves tooth movement
what is IPR and why is it needed?
interproximal reduction
removal small width of enamel of teeth to help make space and align
what is an implant?
titanium double screw cylinder inserted into hole drilled into alveolar bone of either jaw
what is osseointegration?
when the alveolar bone grows around and into hollow screw structure
what kind of tooth replacements can implants have?
single crown tooth
multiple crowns to form bridge
metal bar to act as locking device beneath denture
metal ball to act ad locking device beneath denture
what does successful use of implants depend on?
bone
oral health
lifestyle factors
what is peri-implantitis?
inflammation in gingival soft tissues surrounding implant due to build up of plaque biofilm
what is occlusion?
situation when mouth is closed and teeth of jaws interlock together so occlusal surfaces are in contact
what is an overbite?
upper incisors overlap lowers vertically
what is an overjet?
upper incisors overlap horizontally
what is class I occlusion?
mesiobuccal cusp of upper first molars lies in buccal groove of lower first molar
what is the ideal overjet in a class I occlusion?
2-4mm horizontal overlap
what is the ideal overbite in a class I occlusion?
50% vertical overlap
what is malocclusion?
when normal occlusion isn’t present
what are the types of malocclusion?
crowding
protruding upper incisors
prominent lower jaw
what is crowding and what causes it?
insufficient room for all teeth to erupt in line and occurs in jaws too small to accommodate 32 permanent teeth
can early extraction of deciduous molar contribute to crowding?
yes
what is a class II div I malocclusion?
upper incisors bite in front of lowers causing overjet
what is a class II div II malocclusion?
incisors bite in front and deeper over lowers causing overbite
what is a class III malocclusion?
lower incisors meet either edge to edge or in front of upper incisors
this is a negative overjet
what does supernumery mean?
extra teeth
what is microdontia?
abnormally small teeth erupting in normal sized jaw
what is hypodontia?
congenitally absent teeth
what are the common soft tissue habits?
thumb sucking - prevent teeth erupting normally
