Relining, rebasing, and repairing Flashcards
What is relining?
It involves adding new denture base material to the existing restin to make up for loss of tissue contact causes by resorption of the alveolar ridge
The easiest way to evaluate the space under the denture base is to…
place a thin mix of alginate in the denture base area, seat the RPD, and main until aliginate sets
The alginate to capture a need for reline must be mixed with an _________ water-powder ratio.
increased
- to have minimal tissue displacement
___ scoop of alginate powder mixed with ___ measurements of hot water will provide a mix that is thin enough to not displace soft tissue
1 scoop powder
2 measurements of water
If at least ___ mm of alginate is present under the denture base than you can reline/rebase
2 mm
If the indirect retainer lifts ___ mm or more than you can reline/rebase
2 mm
If the existing denture is short of ideal coverage should you rebase or reline
rebase
If there is a bulk of alignate at the buccal shelf area and the crst of the ridge you should…
reline
You can evaluate loss of support on the distal extension RPD by applying a seating force on the most posterior aspect of the denture and observing an…
interior indirect retainer
If the indirect retainer lifts from its rest seat when applied seating force on the posterior denture base you should…
reline if the space is large (2 mm or more)
How do you prepare a resin denture base for a reline?
remove a uniform amount of denture resin from the intaglio surface of the denture base
For a reline the denture base resin should be removed for 2 important reasons…
- space must be created so the impression material will not apply pressure to the soft tissue
- the surface of the existing rsin must be removed to eliminate potential contaminants and ensure stable bonding
What impression material do you use to reline?
If mobile tissue on the crest of ridge use…
- free-flowing, zinc-oxide eugenol
If dense, firm tissue use…
- any of the polysulfride rubber bases, polyethers, polyvinylsiloxanes, and mouth temp waxes
Tissue-conditioning material can be used as an impression material for a reline but…
they offer no advantage and can easily distort
The most critical step in the reline procedure is the maintenance of the…
tooth-framework relationship during the set of the impression material
The patient should or should not bring teeth into contact during the impression making procedure?
SHOULD NOT
Small defects in the impression can usually be corrected with…
mouth-termperature wax
What should be put in the flask in the lab when doing a reline?
The prosthesis to be relined is located in one part of the flask while the replica of the ednetulous ridge is found in the remaining part of the flask
Which is better: intraoral relines or laboratory relines?
laboratory relines
- avoid an intraoral reline
What is the problem with intraoral relines resins?
they are porous and will lack color stability
What is rebasing?
a lab technique in which the bulk of the denture base is removed and replaced using new resin
Why is a rebase complicated?
retentive meshwork is buried within the deture base without sufficient relief beneath the mesh to allow for adequate bulk of new resin
What are the indications for a rebase?
- denture bases do not extend to cover all of the denture-bearing tissues
- denture base has fractured
- denture base has become irreparably discolored
The denture base is _________________ to allow for room for re-adaptation of the borders with modeling plastic
relieved and shortened
When the border molding is complete the base is covered with a suitable impression material and then the…
final impression is made
What do you do when both the denture base and denture teeth are involved in a situation?
remake
How do you repair a fractured denture base?
- pieces are positively related and luted together using sticky wax
- matrix is poured using dental stone
- fracture line is opened using bur and dovetails are prepared for mechanical retention
- resin is added to prepared fracture line
- placed in a heated pressure pot
- excess repair resin is removed using rotary instruments, finished, and polished
How do you fix the RPD if a tooth pops out?
- displaced tooth is repositioned in the denture base
- matrix is fabricated using rigid PVS
- diatorics are prepared in bottom of tooth for mechanical retention
- tooth is fixed to matrix using sticky wax
- denture base is relieved to permit placement of at least 2mm of repair resin
- resin is placed into the prepared space
- polymerize in heated pressure pot
- remove excess resin
