Provisional extracoronal restorations

Question 1

4 characteristics of a provisional restoration?

Answer 1

• maintain aesthetics
• prevent sensitivity
• preserve tooth vitality by preventing microleakage
• Preserve function

Question 2

What are the two types of provisional restorations?

Answer 2

• Custom formed
• Preformed

Question 3

What material would you use for a provisional crown?

Answer 3

Chemically cured bis-acrylic composite resin

Question 4

What is the use of Svensen gauge?

Answer 4

Measure the amount of tooth reduction , ensuring sufficient reduction for indirect restorations

Question 5

What type of impression would you take for a provisional crown?

Answer 5

Sectional

Question 6

Why you would not use a full arch impression for a provisional crown?

Answer 6

it is difficult to reseat

Question 7

What 3 materials can be used to take an impression for a provisional restoration?

Answer 7

• Addition cured silicone putty
• Alginate
• Softened modelling wax

Question 8

What are 2 advantages of addition cured silicone putty?

Answer 8

• Can be reused
• Resistant to tearing

Question 9

Give 1 advantage and 1 disadvantage for using alginate as an impression material for provisional restorations?

Answer 9

• cheaper
• cannot be reused

Question 10

2 advantages of softened modelling wax as a provisional impression materal?

Answer 10

• easy to adjust
• cheap

Question 11

3 disadvantages of softened modelling wax as a provisional impression material?

Answer 11

• distorts
• cannot be reused
• unsuitable for deep undercuts

Question 12

Alternative of taking a provisional impression?

Answer 12

Custom vacuum formed plastic mould

Question 13

When would you remove bis-acrylic composite resin material? and why?

Answer 13

• in the rubbery stage
• difficult to remove from undercuts if fully polymerised

Question 14

What cement would you use to cement provisional restoration?

Answer 14

Non-eugenol temporary cement material

Question 15

4 materials for preformed provisional crowns?

Answer 15

• polycarbonate
• clear plastic crown forms (filled with composite)
• Aluminum
• Stainless steel

Question 16

2 problems with performed crowns?

Answer 16

• unlikely to fit accurately
• Large bank of crowns is needed (costly!)

Question 17

In what cases would a performed provisional crown be indicated?

Answer 17

Trauma cases where no impression is taken prior to tooth preparation

Question 18

3 ways to remove a provisional crown?

Answer 18

• WAMkey
• Anthogyr
• Sliding hammer

Question 19

3 materials used in indirect provisional restorations?

Answer 19

• composite
• acrylic (most common)
• meta

Question 20

2 advantages of indirect provisional materials? over direct ones

Answer 20

• low shrinkage intraorally
• more accurate
• high strength

Question 21

2 disadvantages of indirect provisional materials? over direct ones

Answer 21

• Time consuming
• Cost

Question 22

2 ways for bridgework temporisation other than custom formed provisional crowns?

Answer 22

• Acrylic removable partial denture
• Essix retainer with pontic

Question 23

What advice would you give the patient regarding flossing a provisional restoration?

Answer 23

• caution with floss as may pull out provisional restoration