Finishing and Polishing Cast Gold & All Ceramic Restorations Flashcards
Steps after waxing up a gold crown
(2)
*Send it to the lab for casting it- they use the same technique I have showed
in my investing and casting lecture earlier.
*Lab returns a gold casted crown with sprue.
Patient Try-In (Lab Procedures – Use Typodont)
(3)
*(Anesthesia when necessary)
*Remove interim crown; clean with explorer / pumice
*Hypersensitivity
Hypersensitivity –
postpone cementation.
*Perfect the interim crown and cement with ZOE (TempBond).
Airway Protection –
Throat Pack
Gauze 4X4 / upright position (not more than 45o recline)
Sequence of Clinical Steps- VVV IMP
(7)
- Proximal contacts
- Internal fit
- Marginal integrity
- (Stability & Retention)
- Occlusion
- External contours
- Surface finish
Patient Try-In: Seating Crown
*Seat crown with finger pressure
*Observe relationship to other teeth and tissues
(2)
*Marginal ridges and proximal contacts
*Marginal closure
—- most often prevent crown from seating intraorally.
*Proximal contacts
Patient Try-In:
#1. Evaluate and adjust proximal contacts
*Proximal contacts most often prevent crown from seating intraorally.
*Mark with
Accufilm; adjust with abrasive wheel
*(Cuttle fine or blue disc; adjust from below and upward)
*Not with a finishing bur or diamond point
*DO THIS FIRST !!!
Craytex Wheel or Fine Sandpaper Disc
Grind from inferior border of heavy marking
Burlew Wheel Finish
Proximal Contacts
Objective:
(2)
*Adjust to correct size, shape, and tightness.
*Leave very slightly tight to allow for final polish.
Proximal Contacts
Procedure:
(3)
*Evaluate contacts visually, with floss, and with shimstock.
*Place articulating film between casting and adjacent tooth, seat crown.
*Selectively adjust region of binding
Selectively adjust region of binding:
(2)
*Inferior portion of mark
*Craytex wheel, Burlew wheel, Shofu Brownie polishing discs
Seating the Crown: Proximal Contacts
*Place the crown and check for appropriate proximal contacts using
shimstock and then Accufilm.
*Check the location and intensity of the proximal contacts:
*Place shimstock interproximally (should drag through with resistance)
Seating the Crown: Proximal Contacts
*Check the location and intensity of each of the proximal contacts:
*Place Accufilm interproximally to evaluate where the crown should be —
*Use the — disc if slight adjustment is necessary; the (2) may be used if more significant reduction is necessary.
adjusted, if necessary.
Blue
separating disc or
diamond disc
Seating the Crown: Internal Fit
*Fit crown to tooth using
Blue Fit Checker (any binding areas are more
easily visible than with White Fit Checker).
Internal Surface (intaglio)
Procedure:
binocular microscope or loupes
*Identify and remove “positive” contacts
*Fit Checker, disclosing wax
*Burn through – nodules, internal line and point angles
*Selective grinding – #1 round carbide
*Remove slight excess
*Indiscriminate removal is unacceptable
*Repeat steps
*Sandblast and steam clean as final step
Fit crown to tooth using Blue Fit Checker*Clinically, if adjustment is necessary, adjust the preparation using
a fine grit
diamond; not the intaglio of the all-ceramic crown.
*Why?
Using Accuflim IV as the fit checker
*Clinically, if adjustment is necessary, adjust the preparation using a fine grit diamond.
Accufilm IV can be used to mark the
intaglio of the crown, which will make a
corresponding mark on the prep.
*Is this normal?
Clean the Restoration
*Clean intaglio surface which has been contaminated with Accufilm IV
using
*In addition, the surface can also be cleaned with
Q-tips and solvent (rinse thoroughly and dry).
etchant gel and rinsed
thoroughly.
Sprue Removal
*Remove the sprue using the
separating disc mounted on the mandrel with the slow-speed handpiece (HP).
*Smooth the roughened surface with the Blue rubber abrasive disc.
Seating the Crown:
Evaluate Complete Seating / Margin Adaptation
*Evaluate the marginal integrity using the
cowhorn or perio explorer for
vertical closure, as well as the horizontal contour and extension.
A small — can be corrected
by carefully adjusting the casting.
overhang
Marginal Integrity
*Check for completeness of seating and marginal adaptation.
*Remove any
*Fine grit diamond disc
*Blue course polishing wheel
over-extension of ceramic material.
Adjustment of long, thick margin
*Remove excess with
*Polish with fine rubber disc
*View from inside / outside casting as you go
Burlew wheel
Margin Evaluation and Adaptation
A small ledge of enamel is generally unacceptable -
increases
the risk of recurrent caries (and sensitivity).
An — margin requires
making a new casting.
open
Open Margin???
(3)
- Heavy proximal contact:
- Internal binding due to distortion or undercut:
- Casting with open margin must be re-made
- Heavy proximal contact:
Re-check it
- Internal binding due to distortion or undercut:
(4)
*Sandblast the internal surface
*Disclose with Fit-checker, aerosol, or disclosing wax
Adjust minimally with #330 or green stone
*Stay away from margin
*Avoid eliminating grooves (unless causing undercut)
- Casting with open margin must be re-made
(1)
*Determine cause and correct it first.
Marginal Adaptation
Procedure:
binocular microscope and/or loupes
“Negative” defect – i.e., short or open margin
*One or two-way catch
*Remake
*Additional visit for new impression, ….
“Positive” defect - i.e., overextension
*One-way catch
*Stone or rubber wheel – slow speed handpiece
*Steady hands
*If margin damaged – remake
Gold Margin Finishing (fully seated casting)
*Burnishing “softened” metal (type III or softer)
*Margin must fit.
*Surface is drawn or moved by rubbing w/ steel point
*Marginal improvement: 30 - 80 microns
*Subgingival (most FGC’s): burnish on die
*Supragingival: burnish & finish (white stone) on tooth
*No finishing on typodontteeth
Occlusal Surface
Procedure:
*Mylar articulating film
*Mark occlusal contacts
*Shimstock
*Evaluate the precision
*Iwanson gauge
*Prevent perforation
*Maintain bulk of restoration
*Adjust premature contacts
*Green stone, white stone, brownie point
*Maintain anatomy of cusp or ridge
Occlusal Adjustment (fully seated casting)
1. Check adjacent teeth without crown in place.
2. Check occlusion with crown in place.
*Use — to determine if the crown is in hyper-
occlusion or infra-occlusion.
shimstock
Occlusal Adjustment
*Locate contacts without crown in place
*Mylar articulating film
*Shimstock
*Visual check amount of “opening” of adjacent teeth
*Use adjacent marginal ridges as guides
*MIP then lateral excursions
Occlusal Adjustment*When complete seating has been verified, mark the occlusal contacts with
Accufilm, and slight adjustments can be made with the fine
grit football diamond
(low high-speed / water) and/or the blue diamond abrasive point (slow-speed /
contra-angle).
Always check the — of the occlusal surface before adjustment.
thickness
Anatomy can be accentuated with a — or diamond (low speed / water),
if necessary.
½ round bur
Adjust heavy occlusal markings(triangular ridges / fossae / marginal ridges)
speed
SLOW-SPEED ONLY
1) Evaluate centric occlusal contact
*Close and squeeze; mandible may deviate
*Shift to the buccal (toward side of restoration)
*Lingual inclines mn buccal cusps / mx lingual cusps
*Shift to the lingual (medial)
*B inclines mn lingual cusps / L inclines mx lingual cusps
*B inclines mn buccal cusps / L inclines mx buccal cusps
2) Check / adjust lateral excursive contact
*“Working side” prematurity
*B inclines mn lingual cusps / L inclines mx lingual cusps
*“Group function” contact on working side
*“Non-working side” prematurity
*L inclines mn buccal cusps / L inclines mx lingual cusps
3) Check and adjust protrusive contact
*Maxillary:
*Mandibular:
distal inclines
mesial inclines
- External Contours
*Physiologic / esthetic contours
*Cervical areas – proper emergence profile
*Proper cusp angulation / contours
*Edge-edge occlusion: cheek biting
*Over-contour / long
Pre-Cementation Finishing and Polishing
*Polish with
rubber abrasive points and discs.
*Brownie – Greenie – Super Greenie
*Avoid over-polishing occlusal contacts / proximal contacts
*Straight handpiece / slow speed
Final Polish with Rouge
*Polish with rouge (Robinson brush / Chamois wheel)
*ABSOLUTELY NOT INTRAORALLY ON TEETH!!
*Clean with Polishing Compound Remover
*No remnant of polishing abrasive
*Prevents cement adhesion → de-bonding
Pre-Cementation Finishing and Polishing
*Re-check the occlusal contacts
*Re-check the proximal contact and contours
Restoration must be CLEANFree of polishing compound, residue (internal), moisture or saliva contamination
*READY TO CEMENT!
Pre-cement-Polish the Restoration
After using the blue coarse polishers on the axial and occlusal surface for adjustment and
shaping / finishing; use the
pink medium disc and point to polish the axial and occlusal
surfaces, respectively.
Pre-cement-Polish the Restoration
*After using the pink medium polishers, use the gray fine disc and points to further polish
the
*The final polish can be obtained using diamond polishing paste and a felt wheel.
Alternatively, the clinical single use Ceramodot and disposable bristle brush can be used.
axial and occlusal surfaces.
Evaluation
*Surface Topography (Intaglio)
(2)
*Tooth preparation is —;
*Ready for cementation (bonding)
*Smooth, no laminations or voids
*Snug, passive fit; clean
CLEAN
Whatever type of crown it is- regardless of the material the steps in
finishing and polishing remain the same except the
burs/
armamentarium changes depending on the type/ material of the
restoration.
