Provisional extracoronal restorations Flashcards
4 characteristics of a provisional restoration?
- maintain aesthetics
- prevent sensitivity
- preserve tooth vitality by preventing microleakage
- Preserve function
What are the two types of provisional restorations?
- Custom formed
- Preformed
What material would you use for a provisional crown?
Chemically cured bis-acrylic composite resin
What is the use of Svensen gauge?
Measure the amount of tooth reduction , ensuring sufficient reduction for indirect restorations
What type of impression would you take for a provisional crown?
Sectional
Why you would not use a full arch impression for a provisional crown?
it is difficult to reseat
What 3 materials can be used to take an impression for a provisional restoration?
- Addition cured silicone putty
- Alginate
- Softened modelling wax
What are 2 advantages of addition cured silicone putty?
- Can be reused
- Resistant to tearing
Give 1 advantage and 1 disadvantage for using alginate as an impression material for provisional restorations?
- cheaper
- cannot be reused
2 advantages of softened modelling wax as a provisional impression materal?
- easy to adjust
- cheap
3 disadvantages of softened modelling wax as a provisional impression material?
- distorts
- cannot be reused
- unsuitable for deep undercuts
Alternative of taking a provisional impression?
Custom vacuum formed plastic mould
When would you remove bis-acrylic composite resin material? and why?
- in the rubbery stage
- difficult to remove from undercuts if fully polymerised
What cement would you use to cement provisional restoration?
Non-eugenol temporary cement material
4 materials for preformed provisional crowns?
- polycarbonate
- clear plastic crown forms (filled with composite)
- Aluminum
- Stainless steel
2 problems with performed crowns?
- unlikely to fit accurately
- Large bank of crowns is needed (costly!)
In what cases would a performed provisional crown be indicated?
Trauma cases where no impression is taken prior to tooth preparation
3 ways to remove a provisional crown?
- WAMkey
- Anthogyr
- Sliding hammer
3 materials used in indirect provisional restorations?
- composite
- acrylic (most common)
- meta
2 advantages of indirect provisional materials? over direct ones
- low shrinkage intraorally
- more accurate
- high strength
2 disadvantages of indirect provisional materials? over direct ones
- Time consuming
- Cost
2 ways for bridgework temporisation other than custom formed provisional crowns?
- Acrylic removable partial denture
- Essix retainer with pontic
What advice would you give the patient regarding flossing a provisional restoration?
- caution with floss as may pull out provisional restoration
