lab 4 Flashcards
What can provide indirect retention
Anything that stops the rotational displacement of the denture due to sticky food
List some problems assorted with lower free end saddles
- Patients find them uncomfortable
- Hard to load abutment teeth
- Denture support is differential
- Saddle rotation
- Lack of resistive to distally directed forces
Give examples of different types of rotation free end saddles can encounter
- Rotation by compression
- Lateral movement
- Backward displacement
What is rotation by compression
Compression of the denture when you bite on the denture
What is bracing
Horizontal movement
In the lower arch what prevents backward displacement of the denture
The pear shaped notches
How can we manage rotation in lower free end saddles
- Try to avoid shortened dental arches
- Try to obtain an impression of the saddle in compressed state
- Cover maximum denture bearing area
- Reduce occlusal tables
- Reduce torque to abutment teeth
- Indirect retention
How can we reduce the occlusal table
- Leave of the 7s
2. Use narrower teeth
How can we reduce torque to abutment teeth
Use the RPI system
How can we try and obtaine an impression of the saddle in compressed state
Take a high pressure impression and reline saddles at fit
Where are rests found on a denture design
On the closest part of the abutment tooth for bounded saddles
How can we achieve retention on dentures
By placing claps as close to the saddles as possible
Create guide planes to increase the effectiveness of clasp
How do we achieve reciprocation on a denture
Best provided by part of the connector or a reciprocal arm
What principles do we need to follow when deciding what connectors to use
- Rigid
- Need gingival clearance
- Simple is better
When do we use the RPI system
When dealing with a lower free end saddle
