Design principles of RPDs Flashcards
Why do clinicians design the denture
We have seen the patient
- tooth condition
- periodontal condition
- motivation
- cost
What are alternative treatments instead of RPDs
- no active treatment
- fixed prostheses (conventional/ resin bonded)
- implants (rarely mix with RPDs as they have no movement)
What is montgomery consent
need patients consent - they need to know their options even if you can’t offer it (i.e. alternative treatments to RPDs)
What are the different aspects of design
- Saddle (s)
- Support
- Retention
- Indirect retention
- Bracing
- Connectors
- Review and simplify
Kennedy classification for bilateral free end saddle
class 1
Kennedy classification for unilateral free end saddle
class 2
Kennedy classification for bounded saddle
class 3
Kennedy classification for anterior bounded saddle crossing midline
class 4
kennedy classification rules
- always go for lowest classification possible
- can have modifications if more saddles
What are saddles
the teeth being replaced
what is support
the resistance of the denture to occlusally directed load
Craddocks classifcation 1
tooth borne
Craddocks classifcation 2
mucosa borne
Craddocks classifcation 3
tooth and mucosa borne
what is retention
resistance of the denture to vertical displacement (lifting away from the tissues)
How can you achieve retention
- clasps (tell technician what undercut you want to go for)
- soft tissue undercuts
- adhesion (maxillary plates)
- friction
- path of insertion
- precision attachments/implants
What is indirect retention
resistance to rotational displacement
What is bracing
prevents a clasp arm moving the clasped tooth
what does the major connector do
connects all the components
what does the minor connector do
connects rests, clasps and bracing arms
Advantages and disadvantages of flanged saddle design
Advantages: good retention, stops food trapping, appearance will stay constant over time
Disadvantages: ?
Advantages and disadvantages of gum fitted/open face saddle design
Advantages:?
Disadvantages: no retention, looks good initially but as resorption occurs you will see a gap (but if patient likes them don’t change)
Where should the support be
- as close as we can to saddles
- consider tooth prep
- depends on mucosa/tooth support
What should you consider when deciding between craddock classifications
- periodontal condition of abutments
- size and position of supporting mucosa
- occlusion/ chewing capability
- aesthetics
