Fixed prosthodontics Flashcards Preview

4th year dentistry > Fixed prosthodontics > Flashcards

Flashcards in Fixed prosthodontics Deck (21)
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1
Q

List five indications for bridgework

A

*Improve function and stability

*Improve appearance

*Speech

*Phycological reasons

*Cooperative patient

*Large teeth

*Heavily restored teeth

*Favourable abutment angulations

*Favourable occlusion

2
Q

List five contraindications for bridgework

A

*Uncooperative patient

*Medical history contraindications

*Poor OH

*High caries rate

*Periodontal disease

*Large pulp (conventional bridge)

*High possibility of further tooth loss

*Length of span too great

*Tilting and rotation of teeth

3
Q

In bridgework define abutment

A

A tooth which serves as an attachment for a bridge

4
Q

In bridgework define pontic

A

The artificial tooth which is suspended from the abutment tooth/teeth

5
Q

In bridgework define retainers

A

The extracoronal ir intracoronal restorations that are connected to the pontic and cemented to the prepared abutment teeth

6
Q

In bridgework define connectors

A

Component which connects the pontic to the retainer(s)

7
Q

Define edentulous span

A

Space between natural teeth that is to be filled by a bridge or partial denture

8
Q

Define saddle

A

Area of the edentulous ridge over which the pontic will lie

9
Q

In bridgework define pier

A

An abutment tooth which stands between and is supporting two pontics, each pontic being attached to a further abutment tooth

10
Q

In bridgework define unit

A

Either a retainer or a pontic. A bridge with two retainers and one pontic is a three unit bridge

11
Q

Describe a fixed fixed bridge and its pros and cons

A

This type of bridge has a retainer at each end with a pontic in the middle joined by rigid connectors.

Advantages; robust design, maximum retention and strength, abutment teeth splinted together, can be used in longer spans, lab construction straight forward.

Disadvantages; Preparation difficult (parallel tooth prep), minimal taper, common path of insertion for abutments, more tooth tissue removal

12
Q

Describe a cantilever bridge and some pros and cons

A

This type of bridge provides support for the pontic at one end only by a conventional crown retainer or a resin retained metal wing.

Advantages; more conservative than fixed fixed. Lab construction straight forward. No need to ensure multiple tooth preps parallel.

Disadvantages; short span only, rigid to avoid distortion, mesial cantilever preferred

13
Q

Describe a fixed movable bridge

A

This type of bridge has a rigid connector usually at the distal end of the pontic and a moveable connector mesially. This allos some vertical movement at the mesial abutment tooth.

14
Q

What is a hybrid bridge?

A

One retainer is a conventional preparation, the other is resin retained

15
Q

Describe what a spring cantilever bridge is and some pros and cons

A

One pontic is attached to the end of a metal arm that runs across the palate to a rigid connector on the palatal side of a retainer.

Advantages; useful if there is spacing between upper incisors. Where adjacent teeth are unrestored. Where a posterior tooth would provide suitabl abutment (already crowned or large restoration).

Disadvantages; can only be used to replace upper incisors. Difficult to clean palatal connector. Difficult to control movement of pontic

16
Q

In bridgework, what is the ideal crown to root ratio?

A

length of tooth coronal to alveolar crest compared to length of root embedded in bone. Optimum 2:3, minimum 1:1

17
Q

What is wash through ridge surface of pontic design?

A

Makes no contact with soft tissue. Funtional rather than for appearance. Consider in lower molar area.

18
Q

What is dome shaped in ridge surface of pontic design?

A

Useful in lower incisor, premolar or upper molar areas. Acceptable if occlusal two thirds of buccal surface visible. Poor aesthetics if gingival third of tooth visible.

19
Q

Describe a modified ridge lap

A

Buccal surface looks as much like tooth as possible. Lingual surface cut away. Line contact with buccal of ridge. Problems with food packing on lingual surface

20
Q

Describe ridge lap/saddle

A

Greatest contact with soft tissue. If designed carefully, can be cleansed. Less food packing than modified ridge lap. Care taken not to displace soft tissues or cause blanching of tissues.

23
Q

List some materials used for conventional bridges

A

*All metal; gold, nickel/colbals chromium.

*Metal ceramic

*All ceramic; zirconia (lava), lithium disilicate (e-max)

*ceromeric (BellGlass)