Components of removable partial dentures Flashcards
What defines the functional depth of the sulcus?
Determined by the anatomy and movement
What determines the width of the sulcus?
Created by the actions of the muscles and frenulum in the impression material
What is support?
resistance to vertical forces directed towards mucosa
What can support a denture?
teeth: tooth borne
mucosa: mucosa borne
tooth and mucosa: tooth and mucosa borne
What are examples of mucosa borne dentures?
every denture
spoon denture
transitional dentures (gum strippers)
Does an evry denture (mucosa birne) have flanges?
yes
How is support achieved in mucose borne dentures?
sanddles
connectors
Where does support come from in tooth borne dentures?
rests
also: connectors, overdenture abutments and occlusal onlays
A = bounded saddle
B = free-end saddle (tooth at one end)
What is a saddle?
is an edentulous region of the alveolar ridge
What type of denture relies on saddles?
mucosa dentures
What is the kennedy classification?
classifies the jaws based on the the of saddles that are going to be replaced
When are the missing 2nd or 3rd molars not included in the kennedy classification?
if they are not included in the design of the denture
describe this kennedy classification
kennedy 2 classification
1 free-end saddle
describe this kennedy classification
kennedy 1 classification
2 free-end saddles
Describe this kennedy classification
kennedy 3 classification
bounded saddle
describe this kennedy classification
kennedy 4 classification
bounded sanddle ant. teeth
what are apelgate modifications?
additions to the kennedy classification
What does apelgate modification refer to?
spaces (not teeth)
Definition of connectors?
rigid components of a denture which hold all other components together
they provide cross-arch stability to help resist displacement by functional stresses
what are the major and minor connectors shown?
pink = minor
black = major
What are types of maxillary major connectors? (4 types)
palata; bar
horseshow (anterior) - usually for kennedy 4 whch are short saddles
anterior-posterior bar
plate
what is the problem with cobalt chrome dentures?
hard to add on teeth
acrylic much easier
How can the plate denture cause periodontal pocket?
connector contact with the gingival margin and cause inflammation and pocket
What are types of connectors for mandibular dentition?
sublingual bar
lingual bar
dental bar
kennedy bar continuous clasp
lingual plate
buccal bar
what is the most commonly prescribed mandibular bar?
lingual bar
Describe a lingual bar
placed in sulcus at highest possible position
needs to be 3-4 mm below gingival margin
connector needs to be 4 mm
need 7-8 mm space below
what is a dental bar?
if you don’t have enough space for a sublingual or lingual bar
placed on the middle third of the lingual surfaces of lower anterior teeth
teeth must be 8 mm in height
What is a kennedy bar/continuous clasp?
dental bar combined with a dental bar
can reduce material and not compromise the longevity of the connector
What is a lingual plate?
last option
made of acrylic or cobalt chrome
extends from lingual sulcus to suprasingular surfaces of teeth
pt need good oral hygiene as it covers the gingival margin
What is a buccal bar?
last resort!
used when teeth are retroclined
cause trauma to buccal tissue
need clear gingival margins by 3mm
What support does a rest provide?
vertical support
What is the role of a rest?
maintains components in their planned position
maintains establishing occlusal relationship by preventing setting of the denture
prevents impingement of soft tissue
directs and distributes occlusal loads to abutments teeth
What are 3 types of rests?
How wide should the base of the rest be?
2.5 mm up to a third across the occlusal surface
Do you need to carve the tooth to place a rest? (rest seats)
yes, around 1.5mm lower the marginal ridge to provide a rest for the rest and minor connector
the prep should dip to allow the cusp to spread pressure apically
