FRAMEWORK TRY-IN Flashcards
trips for the framework try in (3)
-the completed rpd must be passive
-should not exert forces on the teeth or soft tissues
-the tip of each retentive clasp should lie passively in a measured undercut
a — time between the impression and framework try in is desirable
short
allow adequate time for
appointment
PRE-APPOINTMENT EVALUATION
lab returns the framework on duplicate or fitting cast
block out relief wax is placed on the
master cast
This is then Duplicated Twice Using
Hydrocolloid. One
is Poured in Stone and one in High Heat Refractory
Material
The wax-up of the RPD
framework is completed
on the
refractory cast. The
wax relief and block out
is present on this cast.
This cast is usually white
and the material is high
heat investment.
The wax-up of
the RPD
framework is
completed on the
refractory cast
skipped
PRE-APPOINTMENT EVALUATION
dentist is first to evaluate fit on master cast
(4)
-path of placement
-action of retentive and reciprocating arms
-areas of interference/scraping of cast
-accuracy of seating
evaluate external/internal surfaces for
proper finish and construction
INTRAORAL FIT OF THE FRAMEWORK
armamentarium
(4)
good light
magnification
mirror and explorer
fitting and occlusion
FIT OF THE FRAMEWORK TO THE TEETH
(4)
-position direct retainers over abutments
-place fingers over rests and push along the path of placement
-framework should move smoothly with minimal resistance
-balanced resistance should exist
BALANCED RESISTANCE
(2)
-a more rigid retentive tip on one abutment than another will could tilting
0if the framework is not fully seated, the retainers will not be passive and will exert forces against the teeth
EVALUATE EXTERNAL SURFACE OF RPD
(5)
-major connector and minor connector
-rests
-direct retainers
-indirect retainer
0external finish lines
FINISH OF THE INTAGLIO SURFACE
(3)
-remove bubbles, blebs, and artifacts
-surface should be smooth and free from irregularities
-surface is not highly polished
POSSIBLE CAUSES FOR FRAMEWORK MISFIT
(4)
-faulty impression technique
-faulty casts
-tooth movement
-casting inaccuracy
faulty impression (6)
-lack of uniform thickness of impression material
-intraoral distortion due to tray movement
-extraoral distortion due to faulty handling
-improper water to powder ratio
-improper spatulation
-failure to use double pour cast formation technique when making impressions in irreversible hydrocolloid
TOOTH MOVEMENT
(3)
-excessive time lapse from impression to framework try in appointment
-tooth movement due to occlusal disharmonies/periodontal involved teeth
recent extractions
-tooth movement due to occlusal disharmonies/periodontal involved teeth
(2)
-mesially inclined mandibular molars
-lone standing premolars
CASTING INACCURACY
(2)
-expansion of investment
-shrinkage of Ni-Chrome alloys is 2.2-2.4% during casting
FITTING THE RPD FRAMEWORK INTRAORALLY
(3)
-adjust the framework
-adjust the direct retainers
-adjust the occlusion
COMMON AREAS OF FRAMEWORK INTERFERENCE
(4)
-internal surfaces of direct retainer shoulders
-internal surfaces of direct retainer bodies
-internal surfaces of minor connectors
-interdental papilla areas
OTHER AREAS OF FRAMEWORK INTERFERENCE
(3)
-reciprocating arms
-lingual plating
-soft tissue
DISCLOSING MATERIALS TO IDENTIFY
INTERFERENCES
(3)
-NEY spray
-Kerr discolsing wax
-occlude
PROCEDURE TO LOCATE INTERFERENCES
-dry framework
-place thin layer of indicating material
-insert framework along path of insertion
-apply finger pressure
-remove framework and note areas of interference
adjust area of interference with a small bur or stone
-wipe framework clean and repeat procedure until the framework is seating
-the framework should seat w/o a click
-evaluate contact of direct retainers and reciprocating arms
-check for wedging- modification spaces
-adjust the occlusion
-wipe framework clean and repeat procedure until the framework is seating
(2)
-no space around rests and plating
-use air to visualize
OBJECTIVE FOR ADJUSTING THE
OCCLUSION WITH THE FRAMEWORK
assure that the same relationship exists in CR (occlusion) and eccentric functional movement with the framework in the mouth, as exists between the teeth when the framework is not present
ADJUSTING THE OCCLUSION ON THE RPD FRAMEWORK
adjust for CR
(2)
-maintain bulk of rests for strength
-opposing teeth may need modification
