Resilient Processed Liners Flashcards
resilient liners:
a group of
elastomer polymers
resilient liners:
used in a denture when a protective —
resilient surface is needed on the intaglio surface: sensitive mucosa, postradiation mucositis, poor supporting tissue, etc
resilient liners (4)
Xerostomia patients
Hypersensitive mucosa
Bruxers
Knife-edge ridge / atrophy
resilient liners are heat-processed to the denture base as a
“—” procedure
reline
Elastic deformation of the liner allows the
material to
absorb energy/pressure of
occlusion, decreasing pressure on mucosa
resilient liners
materials (4)
Silicone elastomers
Polyurethane elastomers
Vinyl-acrylic polymers
Rubber
resilient liners: other uses (7)
Ridge atrophy – mental foramina, sharp
ridges
Surgery contraindicated (Implants not
possible or implant failure)
Bruxers
Restore congenital/acquired defects—can
engage undercuts with “resilient prosthesis”
Xerostomia – irradiation, medications
Relief areas – median palatal raphe
Single mandibular denture
Length of service ranges from
6 months to 5
years.
in use, the elastic deformaiton of the resillient material
absorbs pressure that would otherwise be transmitted to sensitive tissues
mental base dentures
An indication:
repeated fracture of a
conventional denture. Sometimes seen when
a single denture opposes natural dentition.
metal-base dentures advantages claimed (6)
stronger, less likely to fracture less porous more accurate less deformation of base during function better thermal conductivity better tissue tolerance
metal-base dentures
advantages claimed (3)
disadvantage
Better thermal conductivity
Better tissue tolerance
Less deformation of base during function
difficult to reline
cast metal bases
materials (3)
Ni-Cr or Co-Cr
Gold (Type IV)
Aluminum
tissue changes (4)
Stresses of daily function Changes in general health status Hereditary factors Defects in dentures - produce changes in tissue form
a procedure is needed every — after initial insertion
4-7 years
why reline/rebase (3)
Fit of denture base to the foundation is
poor.
Denture is not stable and/or is non-
retentive.
Denture base is fractured, discolored, or
underextended.
the purpose is to produce an
intaglio surface which fits the mucosa accurately
tissues — from the original form of the denture base
depart
purpose of a reline procedure is to
produce an intaglio surface which fits the mucosa accurately without affecting the occlusion or the OVD
Relining – (2)
replacing the intaglio surface of
the prosthesis
Process of adding new resin to the intaglio
surface of a denture
Rebasing –
replacing the entire denture
base(intaglio and cameo surfaces)
during relining and rebasing occlusal relationship is…
not altered
All of the existing denture base is replaced by
new resin =
Rebase
The occlusal relationship of the teeth is not
altered.
when to reline?
Denture is not retentive, not stable.
relining
existing – should be acceptable
occlusion acceptable at
OVD
CR (error, if present, is slight and is correctable)
when to reline? (4)
existing OVD is acceptable
appearance of teeth and base acceptable
acceptable occlusion at CR (or error is slight and is correctable)
phonetics acceptable
when not to reline? (4)
Teeth grossly malpositioned / worn
Occlusal plane errors
Poor esthetics/phonetics
OVD in error
lining errors to avoid (5)
Increasing the OVD
Denture with impression material is not
fully seated in place increases the OVD
Allowing the denture to move forward
during reline impression step alters the
occlusal relationships.
Allowing maxillary denture to move forward
during impression step
Occlusal relationship errors
remove – undercuts
flange
remove – of resin base
1-2 mm
functional impression with lynal
1-2 hours, some leave for 24 hours
static impression (5)
Closed Mouth technique Patient occludes at OVD Functional movements made with tongue Removed moments later, not hours later Polysulfide, PVS, polyether, etc
when to place the posterior palatal seal?
before processing
children, young adults, acromegaly-
ridges increasing in size, relines needed often
