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Flashcards in Removable Partial Dentures Deck (29)
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1

Path of placement/path of insertion

The specific direction in which the prosthesis is placed on the residual alveolar ridge, abutment teeth, dental implant abutment(s) or attachments.

2

Retention

The quality inherent in the dental prosthesis acting to resist the forces of dislodgement along the path of placement.

3

Guide planes

Limit the path of insertion = better retention

4

Support

The foundation area on which a prosthesis rests; with respect to dental prostheses, the resistance to forces directed toward the basal tissue or underlying structures.

5

Rest seats

Provide support for the prosthesis

6

Saddle

The part of the denture which rests on the foundation tissue and to which teeth are attached.

7

Classification for partial dentures that we use

Kennedy (1925)
Applegate (1960)

8

Class I kennedy classification

Bilateral free end saddles
Rest seats on mesial side of most mesial teeth

9

Class II kennedy classification

Unilateral free end saddle

10

Class III kennedy classification

Tooth bounded saddle

11

Class IV kennedy classification

Free end saddle anteriorly

12

Class V Applegate

Tooth bounded edentulous saddle where the anterior abutment is weak e.g. lateral incisor abutment that is incapable of providing support for conventional RPD and the edentulous space is long.

13

Class VI Applegate

Tooth-bounded edentulous area but restoration can be a fixed partial space as the edentulous space is short and abutments are capable of providing support for the denture

14

Design steps for RPD

1. Saddle
2. Support: rest seats
3. Retention: clasps, guide planes
4. Indirect retention: rest seat
5. Minor connectors
6. Major connectors
7. Simplification - so much metal can we simplify the design

15

Craddock denture types

Tooth-borne
Mucosa-borne
Mucosa- and tooth-borne

16

What is indirect retention?

Resistance to rotation about clasp axis by acting on the opposite side to the displacing force.
(Prevents denture from rocking where there is a free end saddle)

17

RPI System

Rest
Proximal plate
I bar
Whenever there is a fre end saddle, covering more than 180 degrees of the tooth.

18

When would you consider the altered cast technique?

Long saddles

19

Types of rest seats

Occlusal, cingulum, incisal (not placed due to aesthetics)

20

How do you prepare a rest seat?

Marginal ridge is lowered to allow sufficient thickness without creating an occlusal interference - to 1-1.5mm

21

Teeth where rest seats will be provided should be...

Periodontally sound, have enough tooth tissue and good endodontic status

22

How to find out where to place clasps?

Use a surveyor to draw lines over abutment teeth. These lies will show you the bulbosity of your abutment teeth = height of contour and gingival to this is the undercut. Clasps will engage at the undercut.

23

Different types of clasps

Occlusally approaching
Gingival approaching: I bar, T bar, J bar and Y bar

24

When should RPA (Akers) system be used?

Can't accommodate a gingival approaching clasp e.g. not enough gingival sulcus for I bar to engage the tooth or massive bony tuberosity
Rest seat, proximal plate + akers clasp

25

Aesthetic clasps properties

Made from thermoplastic resin, no metal show, great resistance to fracture, lose brightness over time, difficult to adjust and repair

26

Major connectors should be

Rigid, have smooth and rounded line angles, conform to anatomic structures, not interfere with moveable tissues, not allow food entrapment, not cover more tissue than necessary, not use marginal gingiva for support and not impinge on soft and hard tissue.

27

Types of major connectors for maxilla

- Anterior-posterior palatal strap (ring)
- Palatal strap
- Palatal plate
- Horseshoe (if pt gags, bony tuberosity)

28

Types of major connectors for the mandible

- Lingual bar (need minimum 7mm space
- Sublingual bar
- Dental bar
- Lingual plate (most commonly used)
- Labial bar (if pts' teeth are too lingually placed, rarely used e.g. cancer pts)

29

Minor connector

Anything that connects bits of the denture together.