Fabrication of Metal Framework Flashcards
how do you do the design transfer
- transfer design of metal framework to master cast
- surveying table - align tripod marks
- mark retentive undercuts
what is blockout relief
casts are blocked out to eliminate undercut areas that will be crossed by the rigid parts of the RPD
all parts of the framework are ______ except for:
non flexible, clasp tips
arbitrary blockout in less critical areas:
- gingival crevices
- spaces between teeth not in the design
- gross tissue undercuts
- areas that would complicate the duplication process
what is relief
space between the framework and cast/soft tissue
where is relief located
beneath framework, extension in edentulous areas
what does relief provide
attachment of the denture base
- forms internal finish line
what is a refractory cast
prepared master cast are duplicated to produce an exact copy of master cast in investment material
how is the framework pattern fabricated on the refractory cast
using wax
what impression material is used in the making of wax pattern on the refractory cast
reversible hydrocolloid (agar)
what other materials can be used for duplication and refractory cast
alginate, reversible plastic gel (polyvinyl chloride)
what is used to make the refractory cast
investment material
how thick should the pain on layer of investment be
3-4 mm
