Finishing and Polishing Fixed Restorations Flashcards
what are the try in steps
- remove the temporary
- if tooth is sensitive, anesthetic may be required
- once removed clean the preparation with explorer or spoon to remove excess cement
- pumice clean the prep
what should you do if the tooth is super sensitive prior to crown seating
- may delay crown seat
- place two 1- minute coats of gluma
- reseat the temporary with OTC pain meds in use
- monitor for a week or two
what is essential to prevent aspiraition
throat pack with 4x4 gauze with patient in a slightly upright position
what are the crown seating steps
- check proximal contacts
- check internal fit
- check marginal integrity
- check stability and retention
- check occlusion
- check external contours
- check surface finish
- check shade
when you try in crown and it appears to fit marginally and floss snaps contacts what do you do
take a BW xray to confirm radiographic proof of sealed interproximal margins
if there is a gap between the crown and finish line on your prep what is usually the cause
proximal contacts are too tight
what do you do when crown does not seat
- place accufilm between crown prep and tooth intra orally
- use finger pressure to seat crown
- interproximal contacts will be highlighted and now you can see where crown is hitting prematurely
how do you remove excess on contact area on gold crowns
use slow speed wheel
how do you remove excess on contact area with zirconia crowns
fine diamond or slow speed wheel
how do you remove excess on contact area with ceramic crowns
fine diamond or slow speed wheel
what is the technique to polish interproximal contacts
polish or grind from the inferior border of the mark and move occlusally
what is the purpose of moving from inferior border of the proximal contact
you could end up removing the entire contact and crown would have to be remade
what are the objectives of proximal contact adjustments
- adjust contact to lessen its tightness but maintain size, shape and floss snap
- can use shimstock between crown and adjacent tooth to see if it pulls through with resistance
- floss is used to determine strength of contact
what should you evaluate in interproximal contacts
correct location
-size
- intensity with film marking
what do you do if contacts are light with floss but are the correct size and location and the margin is still not sealed
move on to the next step
what is the material we have at UMKC to assess internal fit
fitchecker
how is fitchecker used
- place a small amount in the crown, the crown is then seated and the patient bites on a cotton roll or hold crown until material sets
- remove the crown
- wherever there is show through the crown needs to be adjusted to remove the area
- do not start grinding out any area of the crown internally
what bur do you use to adjust internal fit of crown
2 round bur
how is the internal fit adjusted when using the blue fit checker with an all ceramic crown
same technique but the internal surface of the crown is never adjusted, the preparation is adjusted instead
why do you not want to remove the internal surface of an all ceramic crown
it is specially treated by the lab and if you remove the surface treatment, retention of the crown is much more difficult
what do you do if there is no remaining temporary cement, contacts are light, and no issues are seen on internal fit of the crown and the crown does not seat all the way what do you do
new impression should be made and the patient re-appointed
what do you do if there is no remaining temporary cement, contacts are light, no issues on internal crown and crown seats all the way
a BW x ray is taken to confirm interproximal fit
how do you adjust the margin to a smooth profile when it is overextended
use fine grit diamond disc or blue course polishing wheel
what do you do if the margin is under extended
a new impression should be taken if the seat in the mouth is different then the cast and die
why are under extended margins unacceptable
due to plaque accumulation and possible sensitivity
if there is not an open margin on the cast and die and there is an open margin clinically what do you do
make a new impression
once proximal contacts, internal impurities, and marginal adaptation have been deemed acceptable, check the:
stability and retention
what do you do if the crown rocks or rotates
new impression
when the crown seats well what do you evaluate next
the occlusion
what do you use to evaluate occlusion
accufillm articulating paper
what burs do you use to adjust occlusion
fine diamonds
- green stone
- white stone
- brown stone
since articulating paper doesnt mark well with crowns what do you do
place a thin layer of vaseline on the articulating paper and then check occlusion
what directions do you give the patient to check occlusion
- check in MIP first by having patient “tap,tap,tap” their teeth together
- if that occlusion is registering then ask patient to “close, squeeze, and grind side to side and forward and back” to analyze excursive movements
what do you need to make sure of before adjusting and polishing crown
make sure crown has enough thickness
what do you adjust if the mandible shifts to the buccal
adjust lingual inclines of mandibular buccal cusps and/or maxillary lingual cusps
what do you adjust if the mandible shifts to the lingual
- adjust the buccal inclines of the mandibular lingual cusps and/or lingual inclines of maxillary lingual cusps
- adjust the buccal inclines of mandibular buccal cusps and/or maxillary lingual inclines of buccal cusps
occlusal contacts may cause ____ to deviate upon closing
mandible
what are the non-working side prematurities
adjust buccal inclines of mandibular lingual cusps and/or lingual inclines of maxillary lingual cusps
what are the working side prematurities
adjust lingual inclines of mandibular buccal cusps and/or lingual inclines of maxillary lingual cusps
what do you adjust if there are maxillary protrusive prematurities
adjust the distal inclines
what do you adjust if there are mandibular
adjust the mesial inclines
what should be evaluated on the external contours
- ensure the contours are esthetic and appropriate
- check for proper emergence profile
- proper cusp angulation and location
what is the final step
ensure surface is smooth and polished
how is gold polished
brown and green abrasive points and a shine is placed with robinson brush
what are ceramics polished with
course blue polishers
- then medium pink disk
- finish with the fine white polishers
-last shine given with diamond pastes and bristle brush
when is the crown cleaned
prior to cementation
what is the crown cleaned with
rubbing alcohol for eMax ceramics or ivoclean for zirconia and metals to remove contaminants from saliva or from products used in crown seat appointment
regardless of the crown material, the steps in finishing and polishing are similar except for:
the burs designed for the material you are using
what is the last thing to check
shade
when should adjusting occlusion and contacts be done in relation to cementation
prior to cementation
do you need to make a new impression if there is a shade change
no
