TEMPORISATION Flashcards
provisional restorations
- prothesis that is designed to enhance aesthetics, stabilisation and/or function for a limited period of time after which it is to be replaced by a definitive prothesis
temporary vs transitional
Temporary
- limited and predetermined lifespan
Transitional
- something not planned for the long term but should serve, with modifications (eg aesthetic, occlusal or periodontal changes) for a more extensive period of time, compared to a temporary restoration
functions of provisional restorations
protection maintain tooth position aesthetics diagnosis masticaton facilitate plaque control provide coronal seal in RCT assess prognosis control/customise emergence profile
uses for provisonal restorations
- when there will be a period of time between prep and placemnet of definitive
- routine indirect restorations
- replacing indirect restorations
- immediate tooth replacement
- replace tooth after implant placement
- planning aesthetic, occlusal or periodontal changes prior to definitive restoration
diagnostic uses for provisonal restorations
aesthetic trials
occlusal trials
periodontal changes
chairside provisional materials
polymethyl methacryalte PMMA polyethyl methacrylate PEM Bis Acryl - bis acrylic composites direct composite preformed crowns
PMMA
good aesthetics, strength and wear resistance, easy to repair
sig exotherm and PS
common denture base material
PEM
poorer aesthetics, strength, wear resistance
mostly use to line preformed crowns (IRS snap crowns)
Bisacryl composites
protemp!
good aesthetic
good wear resistance
temp luting agents
zinc oxide eugenol
eugenol free zinc oxide cement (eugenol can inhibit polymerisation of uncured resin)
temp resin cement
zinc polycarboxylate cement
preformed crowns and dis
polycarbonate for anterior teeth
aluminium for posterior
dis
- difficult to adjust marginal adaptation interprox
may need considerabel adjustment
can be relined with PMMA/PEM to improve fit
provisionals made from matricies use what
alginate
- cheap
dissapates exotherm better
not good DS
silicone
- more expensive
- reusable
- can give to patient
indirect/lab based provisionals
- can be made before the crown prep appointment by taking impressions for study models
- some initial reduction can be done on the model and then some provisionals made, these are relined chairside to fit to your preps after tooth prep undertaken
- may start off with direct provisionals until indirect are made (long term, complex cases)
when are provisonals not needed
1) preparations in enamel on non occluding surfaces
2) quick lab turnover time
3) use of CAD CAM in office milled restorations
problem solving
breaking
- minimal preps
relieve inside of pre op impression to increase bulk of provisioanl material then trim chairside
margianl gaps
- reline provisional
ensure adaquate adaptatin of pre op impression
occlusion wrong
- ensure impression fully seated
cant remove provisonal
- ensure vaseline and remoeal during rubber stage
