FP - provisional restorations

Question 1

list 5 functions of a restoration

Answer 1

• protect pulp from thermal, mechanical, electrical and chemical trauma
• maintains the position of the tooth in occlusion
• maintains the periodontal health of the tooth
• restores the aesthetic appearance of the tooth
• protects any root canal filling from coronal leakage

Question 2

when are provisional restorations required (for fixed pros)?

Answer 2

provisional crowns
provisional bridges
provisional dentures/ overdentures

Question 3

what are the 5 methods to create a provisional restoration?

Answer 3

• pre-operative putty impression
• pre-formed crown
• pre-operative wax-up followed by duplication and vacuum-formed stent
• free-hand bis-acryl resin
• use the old crown if there is one

Question 4

what are the 4 materials used for pre-formed crowns?

Answer 4

polycarbonate
cellulose-acetate
composite
(metal)

Question 5

when would metal be used for a pre-formed crown?

Answer 5

hall crowns (stainless steel)

Question 6

you are going to place a crown on a tooth, you dont want to reproduce the tooth in its current shape. How will you create the provisional restoration?

Answer 6

modify the tooth and copy this shape
pre-op model with wax registration - wax up then duplicated in stone and mould made
use the vacuum-formed mould to make the composite additions
crown preps and provisional crowns are made using the same mould

Question 7

what is protemp? and give another name of a product the same

Answer 7

chemically-cured bis-acryl composite resin
Integrity (Dentsply)

Question 7

what material goes in to pre-operative putty?

Answer 7

chemically cured bis-acryl composite resin
(ProTemp or Dentsply)

Question 8

what material is used for a polycarbonate preformed crown?

Answer 8

“directa”

Question 9

what is a polycarbonate “directa” preformed crown filled with?

Answer 9

poly ethyl methacrylate (TRIM)

Question 10

give a unique property of trim

Answer 10

it is haemostatic

Question 11

what are cellulose-acetate preformed crowns?

Answer 11

plastic moulds

Question 12

what are cellulose-acetate preformed crowns filled with?

Answer 12

ProTemp

Question 13

what are properties of composite preformed crowns?

Answer 13

half cured so are malleable and mouldable
long term - 2- 4 years

Question 14

what technique can be used to make provisional restorations for multiple teeth where we want to change the occlusion?

Answer 14

pre-operative wax-up followed by duplication and vacuum-formed stent

Question 15

what technique for provisional restoration can be used as a last resort when you can get no matrix in place?

Answer 15

free-hand bis-acryl resin

Question 16

when can you use a provisional post crown?

Answer 16

when existing root canal is satisfactory
simple replacement of post crown only

NOT when undertaking RCT or replacing root canal filling

Question 17

when would you want to use a provisional overdenture?

Answer 17

easy access to root surface for RCT or re-RCT
less coronal leakage during tx
likely better long term result

Question 18

what happens to the provisional if the crown prep is undercut?

Answer 18

it will not withdraw from the prep
it will tear as withdrawn

Question 19

how thick should an ideal provisional crown be?

Answer 19

more than 0.5mm thick

Question 20

list the therapeutic uses of provisional restorations

Answer 20

improve gingival/ perio health prior to taking imps
improve speech difficulties
improve appearance of the final restorations

Question 21

how may provisional restorations improve gingival/ perio health?

Answer 21

better contour allows access to cleaning and improved gingival health

Question 22

how may provisional restorations improve speech difficulties?

Answer 22

changing the contours of palatal surface of anterior teeth
then copy successful prov rest contour for the definitive

Question 23

at what stage should you make the provisional restoration?

Answer 23

after tooth prep
before imps