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BDS 2 OSCE > RPD Design > Flashcards

Flashcards in RPD Design Deck (25)
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1
Q

What is support?

A

Resistance of a denture to occlusally directed loads

2
Q

What can be used for support?

A

Rests - occlusal, cingulum, ring, incisal and ledge

3
Q

What is direct retention?

A

Resistance to vertical displacement of the denture

4
Q

What can be used for direct retention?

A

Clasps - occlusally or gingivally approaching

5
Q

How do clasps work?

A

Provide direct retention by engaging the undercut portion of a tooth
The action of a clasp must be resisted by either a non-retentive clasp arm above the maximum bulbosity or by a reciprocal connector

6
Q

What are the different clasp lengths?

A

CoCr - 0.25mm
Gold - 0.5mm
SS - 0.75mm

7
Q

What is indirect retention?

A

Resistance to rotational displacement of the denture

8
Q

When is indirect retention used?

A

In dentures with free end saddles

9
Q

What does indirect retention do?

A

Prevents displacement of the denture around the fulcrum axis

10
Q

What is the fulcrum axis?

A

The axis around which a tooth and mucosa borne denture tends to rock when the saddle is rocked

11
Q

What is a major connector?

A

Joins together component parts of a denture

12
Q

Give examples of maxillary major connectors

A

Anterior plate, posterior bar, palatal plate

13
Q

Give examples of mandibular major connectors

A

Lingual bar (needs 8mm), lingual plate, sub-lingual bar

14
Q

What is Kennedy Class I?

A

Bilateral free-end saddle

15
Q

What is Kennedy Class II?

A

Unilateral free-end saddle

16
Q

What is Kennedy Class III?

A

Unilateral bounded saddle

17
Q

What is Kennedy Class IV?

A

Anterior bounded saddle only

18
Q

What is Craddock Class 1?

A

Tooth borne - hard tissue resistance to occlusal loading

19
Q

What is Craddock Class 2?

A

Mucosa borne - large coverage provides resistance to loading

20
Q

What is Craddock Class 3?

A

Tooth and mucosa borne - hard tissue and large coverage in case of fewer teeth and large edentulous saddles

21
Q

What is the RPI system?

A

Stress relieving clasp system used in free-end saddle designs to prevent stress on the last abutment tooth

22
Q

What makes up the RPI system?

A

Rest
Proximal plate
I-bar clasp

23
Q

Describe the rest in the RPI system

A

Mesial to the tooth, rounded on the impression surface

24
Q

Describe the proximal plate in the RPI system

A

Guide surface 2-3mm, undercut to permit movement

25
Q

Describe the I-bar clasp in the RPI system

A

Greatest prominence of the tooth contour