Provisional Restorations Flashcards
5 methods of providing a PROVISONAL restoration?
- Pre-operative putty impression.
- Pre formed crown.
- Pre-operative wax up followed by duplication and a vacuum formed stent.
- Free-hand bis-acrylic resin.
- Use the old crown if there is one.
5 functions of a provisional restoration?
- Protect the pulp from mechanical, thermal, electrical and chemical trauma.
- Maintain the position of the tooth in occlusion.
- Maintain the periodontal health of the tooth.
- Restore the aesthetic appearance of the tooth.
- Protect any root canal filling from CORONAL LEAKAGE.
4 materials a preformed crown can be made of?
- Polycarbonate
- Cellulose-acetate.
- Composite
- Metal
4 steps to the putty impression provisional crown technique WITH modification.
- Make PRE-OP MODELS in stone with WAX REGISTRATION of bite.
- Technician does a WAX UP to improve the SHAPE and AESTHETICS of the teeth.
- The wax up can be DUPLICATED in STONE and a VACUUM FORMED STENT MADE.
- STENT/MOULD used after crown preparation to make PROVISONAL CROWNS
What can the vacuum stent mould made in the modified putty impression technique be used for other than providing provisional crowns?
Can be used PRIOR to crown preparation to make COMPOSITE ADDITIONS to the teeth.
What material goes into the pre-operative putty/ the stent?
chemically cured bis-acrylic composite resin
protemp, integrity
Which preformed crowns are most commonly used?
POLYCARBONATE crowns (directa)
What is added into polycarbonate crowns prior to cementation?
a COLD CURE ACRYLIC RESIN (ex. TRIM).
It is a pema
3 benefits of trim?
- bonds to crown.
- does not fall apart when trimmed.
- can be polished.
3 tips on manipulating trim?
- Lift slightly off the preparation at initial set to pull over any undercuts.
- Do not fully remove until almost set (otherwise will not go back on)
- Acrylic burs more effective at cutting than abrasive discs.
what is used to cement temporary polycarbonate crowns in place?
TEMPORARY LUTING CEMENT (EX. tempbond).
9 Steps to the provision of a temporary cellulose acetate crown?
- Cut to size with crown shears
- Perforate incisal corner to let out trapped air
- Fill with ProTemp
- Place over prep and allow to cure
- Remove from prep
- Remove cellulose acetate
- Polish margins
- Check occlusion
- Cement
What is used to fill the cellulose acetate crown?
PROTEMP
Why are metal provisional crowns not encouraged?
Poor margins that form PLAQUE TRAPS
5 steps to providing a provisional metal crwown?
- Select.
- line with Protemp.
- Check margins
- Check occlusion
- cement with temporary luting cement (tempbond).
Technique to provide a temporary bridge when the abutment tooth is prepared and there is no pre-operative putty without using the lab (6)?
- Mould some soft wax over the abutment and gap.
- make a putty index over the wax.
- Place protemp into the putty and place over the tooth.
- Trim up the protemp temporary bridge.
- Check the occlusion .
- Polish and fit with temporary luting cement (tempbond)b
When is a pre-operative wax up followed by duplication and a vacuum formed stent used?
When making temporary restorations for MULTIPLE TEETH and wanting to CHANGE OCCLUSION or GUIDANCE.
Technique to provide a temporary bridge when the abutment tooth is prepared and there is no pre-operative putty WITH using the lab (9)?
aka post-operative wax up followed by duplication and vacuum formed stent.
- Take an impression.
- Technician makes the wax.
- Technician duplicates the cast.
- Technician makes a vacuum formed stent.
- Fill stent with tprotemp.
- Trim
- Check occlusion
- Polish
- Cement with temporary luting cement (Protemp).
When is a free hand bis-acrylic resin temporary restoration used?
As a LAST RESORT as it requires A LOT OF TRIMMING and is VERY TIME CONSUMING.
2 diagnostic benefits of provisional restorations?
Help check for UNDERCUTS ON CROWN:
- will not withdraw from preparation.
- rstoration will tear as it is withdrawn.
Help check if prep is ADEQUATELY REDUCED:
- did you cut through the provisional crown when checking the occlusion.
- is the provisional crown less than 0.5mm thick?
why do we make our provisional restoration before taking our final impression?
- Provisional restoration tells us if CROWN PREP IS UNDERCUT.
- Tells us if prep is ADEQUATELY REDUCED.
When do we make our provisional restoration?
- AFTER the tooth preparation (to check the tooth preparation is satisfactory)
- BEFORE the impression (so you can modify the preparation BEFORE the impression is taken.
3 THERAPEUTIC benefits of provisional restorations?
- improve PERIODONTAL health.
- improve SEECH DIFFICULTIES.
- improve AESTHETICS (+ confirm patient is happy with aesthetics).
