FINISHING AND POLISHING
The surface of the casting that is
retrieved from investment is too
rough for use in the mouth.Five
preparatory procedures need to be
performed on any type of
cemented restoration after it has
been fabricated
PROCEDURES
Preliminary finishing
Try-in & adjustment
Pre-cementation polishing
Cementation polishing
Post-cementation finishing
• The internal and external aspects of
restoration are handled differently.
• External surface smooth &perfect
uninterrupted transition from restoration
to tooth
• Rough surface plaque accumulationinjurious to health of periodontal tissue
• Try in satin finish after chairside
adjustment high luster
• Finishing&polishing- accomplished with
fixed routine-coarse and fine
ABRASIVES AND POLISHING
MATERIALS
• ABRASIVES:exceptionally hard material
that develop sharp cutting edges when they are
chipped.
• POLISHING MATERIALS:abrasives
of softer material that are reduced to extremely
fine particle size.
COMMONLY USED ABRASIVES
AND POLISHING MATERIALS
DIAMOND
SILICON CARBIDE
EMERY
ALUMINIUM OXIDE
GARNET
SAND
CUTTLE
TRIPOLI
ROUGE
TIN OXIDE
COMMONLY USED FORMS
SEPARATING DISCS
MOORE’S DISC
HEATLESS STONES
BUSCH SILENT STONES
GREEN STONES
PINK STONES
WHITE STONES
RUBBER WHEEL AND POINTS
ZONES OF FINISHING AND
POLISHING
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•
•
•
•
•
•
ZONE 1:INTERNAL MARGIN
ZONE 2:INTERNAL SURFACE
ZONE 3:SPRUE
ZONE 4:PROXIMAL CONTACT
ZONE 5:OCCLUSAL SURFACE
ZONE 6:AXIAL WALL
ZONE 7:EXTERNAL MARGIN
PRELIMINARY FINISHING
OF GOLD RESTORATION
PROCEDURES…
Inspect under surface of cast under magnification for
small nodules or bubbles
Remove nodule with no:330 bur in high speed
.Trace negative angles on inside of occlusal surface
with tip of bur
Ideally the cast should touch the die only in the
marginal region –there should be a slight gap every
where else for future cementation.
A uniform space of 25 – 35micrometer necessary
If nodules present removed with round carbide
bur
Use a separating disc to cut the sprue from the
casting
Diagonal cutting plier may be used.
Hold hand piece with a firm pen grasp while
cutting the sprue next to the casting
Avoid tipping the disc- if a disc binds in the cut
grooves – it may flip the casting out of our hand
After removing the sprue , use separating to trim
the remaining portion of sprue attachment on the
casting until the contour in that area is continuous
with the contour of the restoration surrounding the
sprue
Sprue immediately adjacent to the
casting is removed with separating disc
Use coarse rubber disc-to smooth away the
roughness left by the separating disc.
Use finer Burlew/gold lustre blue disc in
similar manner after coarse disc-now entire
surface smooth with satin finish
Axial surface finished to the margin-do not
extend over the margin-seat the restoration
on the cast
Adjust the interproximal area-until
restoration seats completely with contacting
adjacent teeth
Axial surfaces are smoothed with Burlew
wheel
Adjust occlusion in articulator-centric&eccentric
Remove restoration from working cast and place it
back to die
No:0-”bud” finish bur – to smooth grooves on
occlusal surface
Smooth cusp tips and blend them into the grooves
on the occlusal surface with a small rubber sulci
disc
External surface should have a satin like finish
produced by Burlew rubber polishing wheel
TRY-IN & ADJUSTMENT
If careful and gentle no need of
anesthesia
Patient’s unimpaired tactile sense can be
valuable during adjustment of occlusion
Small safety ring provided by cutting a
thin slice from hollow sprue
Attach it to the wax pattern where it
will not interfere with occlusion
Thread floss through the ring before
trying casting in the mouth.
A safety ring may be fashioned by
cutting a thin slice from hollow sprue
Ring is luted to wax pattern
A length of dental floss is looped through
the ring on the casting
Floss is allowed to hang out the corner
of the mouth
• Remove provisional restoration by
grasping the buccal and lingual surface
with tips of backhaus towel forceps and
rocking it to the facial and lingual.
• Remove the left cement particles
• Wipe of prepared surface with cotton
pellet ( dry )
• Wash with luke warm water
Provisional restoration removed
with backhaus forceps
A)Richwil crown remover soaked in hot water
B)patient closes on softened cube
C)patient opens quickly and forcefully to
remove crown
Evaluation of restoration in
following sequence:
Proximal contact
Margins
Occlusion
Contour
Esthetics
Adjustment of proximal surface
contact
Proximal contact – neither too tight nor too light.
Place the restoration on the tooth & seat it with firm
finger pressure.
Do not mallet / apply occlusal pressure.
Crown can be removed with Richwil crown remover

soaked in hot tap water for 1min
Patient closes on the softened cube
Patient opens quickly and forcefully to remove crown
 Test for proximal contact
with waxed dental floss
 Satin finish on gold
restoration advantageousshiny burnished
area where tight
contact occurs
Marginal adaptation
After proximal
contact corrected
seat restoration
and examine
margin closelyshould not be ;
Overextended
Under extended
Too thick
Open- gap greater
than 50µm
Various materials used to detect
discrepancies
 Chloroform & rouge / thinned typewriter
correction fluid-painted in the internal surface
 Thin layer of dry aerosol indicators – sprayed
 DISCLOSING WAX:
 Fill restoration ½ full of disclosing wax
 Heat in flame to flow the wax & adhere to inner surface
 Teeth wet with saliva( avoid sticking of wax)
 Wax solidified
seat restoration hold for 10 sec
then remove
Areas of metal – tooth contact –
appear as shiny spot devoid of wax
Relief impinging areas with no:30 burallow restoration to seat further
Remove disclosing material by
swabbing with chloroform and sand
blasting
Tooth cleaned with cavilax
GOLD MARGIN FINISHING
 2 types of margins- sub gingival & supragingival
 Casting placed on prepared tooth and have the patient seat
it by closing on plastic bite wafer/wooden stick
 Burnishing and marginal adaptation with dull spratley
knife(30µm adaptation)
 Finishing with white stone (60µm adaptation)
 Final precementation smoothening with 3/8 inch cuttle
disc
All accessible margins are burnished
intraorally with a smooth dull
instrument
Margins are finished with a white
stone rotating from gold to tooth
OCCLUSAL ADJUSTMENT
Ask the patient to close in customary position
Check if patient can hold the shim in between
adjacent teeth with crown out – if not the
crown too high
Ask the patient to bite in centric relation
Force until all teeth touch
Cntd…..
• If mandible shifts to
side of restoration
• Buccal incline of
maxillary lingual cusp
/ lingual incline of
mandibular buccal
cusp adjusted
• If mandible shifts
away from restoration
•
BULLS
If patient can hold shim stock on adjacent teeth
with the crown out,but not with it , the crown is
too high
Premature contact on buccal incline of maxillary
lingual cusp produces buccal shift to mandible
Premature contact on lingual slope of maxillary buccal
cusp produces lingual shift of mandible
Premature contact on lingual incline of maxillary
lingual cusp produces lingual shift of the mandible
NON WORKING MOVEMENTS
•
Non working interference
NON WORKING MOVEMENTS
•
Working interference
CONTOUR
• Improper contour-impaired gingival health
• Excessive convexity near gingival margin
•
•
Plaque accumulation
ESTHETICS
• Restoration viewed from conversational
distance- see if contours harmonize with
rest of patient’s dentition
• Let patient look in a mirror
PRE CEMENTATION POLISHING
Polished to high shine
polish axial surface with Tripoli on soft bristle brush
occlusal anatomy restored (171 L carbide bur )
• Shiny finish
• Matt finish (sandblasting)
• Enable observation of
facets/burnishing produced by
occlusal contact after casting in
mouth
Masking tape is wrapped around the
casting
Only the occlusal surface left
uncovered
Casting placed in sand blaster
Air brush used to apply a matte finish
to occlusal surface of the casting
POST CEMENTATION
FINISHING
 Occlusion checked
 Finishing with fine rubber point
 White polishing stone with lubrication
(petrolatum)
 To inaccessible areas
 Fine cuttle disc
 Pumice and rubber cup
 FINAL POLISHING by – intraoral
amalgloss
Thank
you
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FINISHING AND POLISHING of fpd