2 Flashcards
(24 cards)
Intracoronal/extracoronal
post into the tooth, extracoronal resists displacmeent using components placed on or attached to the external surfaces of the abutment tooth.
Clasp type retainer
what we’ll be using
Clasp assembly parts
Rest
Retentive arm
Reciprocating arm
Guiding plate
Rest
supports and prevents from seating too far.
Guiding plate
flat interproximal plate to guide in the RPD. Tooth may be flattened a bit.
undercut dimension
0.01inch
Support provided by
occlusal rest - can also be in cingulum?
Retentive arm preferably on
buccal, unless curve of wilson is really pronounced (mand molars)
Cingulum rest seat
aesthetic, usually in canines
Incisal rest
looks bad, used when cingulum is not practical
Cast circumferential clasp best for
kennedy class III arches
Embrasure clasps used when
no mod spaces on opposite side of arch, or kennedy class IV.
With embrasure clasps, ——————- are needed to avoid wedging
double rests
Passivity
like a watch on your arm, freely moving. Not too much force on teeth.
Support
resistance to vertical seating forces.
Adequate encirclement
180deg or more
Minor connector
connects major connector with other components like rests. Guide plates also provide stabilization
Denture base
mesh (less interarch space)
open lattice
nailhead (butt acrylic tooth)
—— denture base is most used
open lattice
Nailhead benefit
retention gained due to metal projections on the metal surface
Acrylic resin joins metal at a butt joint to prevent over
thinning of acrylic. Interal finish lines on tissue side
External finish lines
should be sharp, definite, slightly undercut to adhere to resin. Angle should be acute.
Internal finish line
formed from margins of the relief wax used over edentulous ridge.
If lingual bar, go
all the way back to involved molars if need be.
