HEAVY EMPHASIS: 241-263

Question 1

what does it mean for the restoration to be fabricated of a mataerial that will prevent conduction of temp extremes. margins should be adapted well enough to prevent leakage of saliva

Answer 1

pulpal protection

Question 2

tooth should not be allowed to extrude of drift in any way. any such movement will require adjustments or a remake of the definitive restoration at the time of cementation

Answer 2

positional stability

Question 3

Being able to function occlusally with the provisional restoration will aid patient comfort, ward off tooth migration, and possibly prevent joint or neuromuscular imbalance.

Answer 3

Occlusal function.

Question 4

The restoration must be made of a material and contour that will permit the patient to keep it clean during the time it is worn. If the gingival tissues remain healthy while the provisional crown is in place, there is less likelihood of a problem arising after cementation of the definitive restoration.

Answer 4

Ease of cleaning.

Question 5

It is of utmost importance that the margins of a provisional restoration not impinge upon the gingival tissue.1–4 The resulting inflammation could cause gingival proliferation, recession, or at the very least hemorrhage during the impression or cementation. A damaging overhang can result from a preformed metal or resin provisional restoration that has not been contoured properly, while a custom resin provisional crown can produce a horizontal overhang if it is incorrectly trimmed. A restoration with drastically underextended margins also may result in a proliferation of gingival tissue.

Answer 5

Nonimpinging margins.

Question 6

The restoration must stand up to the forces to which it is subjected without breaking or coming off the tooth. Replacement of a provisional restoration is time-consuming and detrimental to patient rapport. A broken provisional fixed partial denture can accelerate tooth movement. The restoration should also remain intact during removal so that it can be reused if necessary.

Answer 6

Strength and retention.

Question 7

In some cases, the restoration must provide a good esthetic effect, particularly on anterior teeth and premolars.

Answer 7

Esthetics.

Question 8

what resins can be used for making custom provisional restorations

Answer 8

1. PMMA (longest used)
2. PEMA
3. PVEMA
4. Bis-acryl composite resin
5. VLC urethane dimethacrylate

Question 9

what are techniques for custom provisional restorations

Answer 9

1. overimpression-fabricated provisional crown
2. template-fabricated provisional fixed partial denture
3. template-fabricated VLC provisional rsetoration
4. shell-fabricated provisional restoration
5. overimpression-fabricated bis-acryl composite crown

Question 10

what are techniques for prefabricated provisional restorations

Answer 10

1. anterior polycarbonate crown
2. provisional crown for an endodontically treated tooth
3. preformed anatomical metal crown

Question 11

what type of overimpressions can be made to shape provisional restoration? is this done in mouth or on cast?

Answer 11

elastomeric and alginate; can be done on either cast or mouth before tooth prep has started

Question 12

why is alginate overimpression a popular technique

Answer 12

because it is readily available in dental operatory and can be easily adpated to intraoral use in the event that the plan for restoration of a tooth with amalgam is unexpectedlyy changed for cast restoration

Question 13

the overimpression is frequently made in patients mouth when

Answer 13

while waiting for anesthetic to take effect

Question 14

what is the best technique for custom provisional restorations for esethetic anterior cases and provides better stabilization of teeth for posterior cases?

Answer 14

template-fabricated provisional fixed partial denture

Question 15

why is a transparent template essential to the use of VLC resin?

Answer 15

because the clear matrix allows the light access to the resin to initiate polymerization

Question 16

is template fabricated VLC provisional restoration completed in mouth or on cast

Answer 16

diagnostic cast

Question 17

what is shell fabricated provisional restoration made of

Answer 17

any acrylic resin and is then relined directly on quick-set plaster cast

Question 18

example of when to use a prefabricated provisional restoration

Answer 18

patient may present with emergency situation where a posterior tooth has fractured and there is not time available for definitive tooth preparation and a custom provisional crown