BDS2 RPDS revision

Question 1

What is a saddle area?

Answer 1

an edentulous aeea
- the area of missing teeth to be restored with a partial denture

Question 2

what is a saddle?

Answer 2

part of the denture that carries the replacement prosthetic teeth to fill the edentulous area

Question 3

types of saddle area

Answer 3

bounded saddle
free-end sadd

Question 4

Kennedy Class I - define

Answer 4

bilateral free-end saddles

Question 5

Kennedy class II - define

Answer 5

unilateral free-end saddle

Question 6

Kennedy Class III - define

Answer 6

bounded saddle

Question 7

Kennedy Class IV - define

Answer 7

Anterior bounded saddle
crossing the midline

Question 8

Give the Kennedy classification for an anterior saddle that does not cross the midline?

Answer 8

Kennedy Class III

Question 9

In dentures with multiple saddles, which saddle is used to classify the arch?

Answer 9

the most posterior saddle

Question 10

Define the term ‘support’ in relation to partial dentures

Answer 10

the resistance of a denture to occlussally directed load

Question 11

How to improve support for a denture?

Answer 11

utilise remaining natural teeth
spread load over large surface area (soft tissue)

Question 12

Craddock class 1 - define

Answer 12

tooth borne

Question 13

Craddock Class II - define

Answer 13

mucosal borne

Question 14

Craddock class III define

Answer 14

a combination of hard and soft tissue coverage

Question 15

tooth supported dentures - features

Answer 15

transmits load via periodontal membrane
allows supported denture base to feel like the natural dentition
is more comfortable for patient
protects soft tissues from trauma

Question 16

mucosal supported dentures - features

Answer 16

must cover as large an area as possible
allows denture base to move slightly
- possible damage to adjacent gingival margins

Question 17

Function of rests in RPDs

Answer 17

components which provide support for denture from vertical opposing forces

Question 18

What material is usually used for rests

Answer 18

cast metal

Question 19

Types of rests used in RPDS

Answer 19

cingulum, occlusal or incisal

Question 20

Why are large rests more suitable than smaller rests?

Answer 20

they can direct force down the long axis of the tooth

Question 21

benefits of occlusal rests

Answer 21

prevent movement of the RPD towards the mucosa
assist the distribution of occlusal load
prevent over eruption of unopposed teeth
can provide indirect retention

Question 22

features of incisal rets

Answer 22

used mostly on lower anterior teeth
poor aesthetic appearance
may interferer with incisal occlusion

Question 23

Cingulum rests - features

Answer 23

preparation required if prominent cingulum not available
most commonly used on canines
aesthetically superior to incisal rests
less likely to breakage than incisal rets
applies stress at a lower level

Question 24

The default position to place a rest for a bounded saddle is…

Answer 24

immediately adjacent to the saddle

Question 25

The default position to place a rest for a free end saddle is...

Answer 25

NOT immediately adjacent to the saddle

Question 26

Rest position for tooth supported bases

Answer 26

Should be placed on the tooth surface nearest to the base

Question 27

Rest position for Craddock Class iii bases

Answer 27

should be placed on the tooth surface which is not next to the base - opposite side of tooth from saddle area

Question 28

possible consequences of rest seats

Answer 28

destruction of tooth surface exposure of dentine loss of occlusal stop when denture is not worn

Question 29

Define 'retention' in reference to RPD design

Answer 29

the resistance of a denture to vertical dislodging forces

Question 30

How can retention be achieved in an RPD?

Answer 30

mechanical - clasps muscular - shape of the denture physical - mucosal coverage

Question 31

indirect retention - define

Answer 31

resistance to rotational displacement of the denture

Question 32

What is a denture clasp?

Answer 32

a metal arm that, when in position, contacts the tooth preventing removal of the denture base

Question 33

where are denture clasps placed?

Answer 33

below the undercut of a tooth

Question 34

where are undercuts found?

Answer 34

below the most bulbous part of a tooth

Question 35

how are undercuts identified?

Answer 35

from surveying the cast

Question 36

Give the name for a gingival approaching clasp

Answer 36

I-bar clasp

Question 37

What is a gingivally approaching clasp?

Answer 37

a clasp that approaches the identified undercut via the gingival margin

Question 38

what is an occlsually approaching clasp?

Answer 38

a clasp that approaches the identified undercut from above the maximum bulbosity of the tooth

Question 39

types of occlusally approaching clasp

Answer 39

self reciprocating clasp single arm clasp with separate reciprocating arm

Question 40

depth of undercut required to place a clasp in a CoCr framework

Answer 40

0.25mm

Question 41

Give examples of indirect retainers

Answer 41

major connectors minor connectors rests saddles denture base

Question 42

What is a connector?

Answer 42

the rigid part of a denture base that unites other components

Question 43

ideal features of a minor connector

Answer 43

rigidity covers as little gingival tissue as possible crosses the gingival margin at right angles - to maintain gingival health

Question 44

Minor connectors - function

Answer 44

joins components such as rests to the major connector provides indirect retention by resisting movement about the axis of rotation

Question 45

major connectors - ideal features

Answer 45

be ridges avoid covering gingival margin s be comfortable with as few edges as possible

Question 46

types of maxillary major connectors

Answer 46

palatal plate posterior bar anterior plate mid palatal plate horseshoe bar horseshoe plate

Question 47

common connector choice for Craddock class 1 cases

Answer 47

bars

Question 48

connector choice for Craddock class 2 cases

Answer 48

plates

Question 49

types of mandibular connectors

Answer 49

lingual bar dental bar lingual plate sub-lingual bar lingual bar with dental bar

Question 50

RPI system use cases

Answer 50

distal extension RPDs - Kennedy class 1 and class 2

Question 51

Which components make up an RPI system

Answer 51

mesial rest proixmal guide plate gingival approaching I-bar clasp

Question 52

Function of the RPI system

Answer 52

used in free end saddle designs to prevent stress on the last abutment tooth