zweig - digital Flashcards
broad - what is digital dentistry
electronic recors photos radiographs patent communication software digital impressions computer aided milling music in office telephone systems
software
x-rays
goes on to say everything
can someone tell me what a CEREC crown is?
basically doing ___ material crown with cad cam technology
procedural steps needed to complete a traditional fixed restoration
1-10
- decide material
- anesthetize
- prepa
ration of tooth to meet requirements of material - isolation
- retraction
- elastomeric impression
- temporaization
- send to lab
- 2nd visit to try in and adjust
- cement
procedural steps needed to complete a CAD/CAM fixed restoration?
- choose material
- anesthetize
- prepare tooth
- isolation
- retract
- digital scan of quadrant with the prepped tooth, the opposing quadrant
. and the bite relationship - mill f the restoration
- try in and adjust occlusion
- bond the restoration
digital scan of what with CAD/CAM fixed restoration
scan of the quadrant with the prepped tooth
the opposing quadrant
and of the bite relationship
the ‘only’ differences are
different prep design
digital scanning/ no elastomeric impression
ability to control the design of your restoration
in office milling - no lab fees
can be delivered in a single visit which would mean no temporizaton
materials available in school
- vita mark II
- enamic
- IPS e.max CAD
- celtra duo
- zirconia
flexural strength, indications, post milling processing, and appointment time for vita mark II
flexural strength, indications, post milling processing, and appointment time for
emax needs to be
glazed and fired all the time
flexural strength, indications, post milling processing, and appointment time for enamic
flexural strength
- 112.4 MPA
indications, post milling processing, and appointment time for
why using the material we are
EXPOSURE -
using a wide variety of material - more clinical experience and knowledge of the materials avaialble
flexural strength, indications, post milling processing, and appointment time for IPS e.max CAD
flexural strength, indications, post milling processing, and appointment time for
flexural strength, indications, post milling processing, and appointment time for celtra duo
flexural strength, indications, post milling processing, and appointment time for
flexural strength, indications, post milling processing, and appointment time for zirconia
flexural strength, indications, post milling processing, and appointment time
which materials do not require a sintering cycle in the oven? implication?
Enamic, vita mark II and celtra duo
cuts down on post-milling processing time in one visit restorative appointment
*also one of the reasons
at school why we use these
types of cerec optical scanner
blue cam
omni cam
blue cam
individual pictures that are stitched together
requires optical powder on tooth surface
most pictures taken in long axis of tooth only
omni cam
VIDEO - NO POWDER
- must capture all tooth and soft tissue data
sirona cerec details
the system we use in school
30+ years of CAD/CAM
integration of CBCT
optimal conditions for digital scanning
- ACCESS
- GINGIVAL HEALTH
- ability to completely isolate the area to be scanned especially if using BLUECAM
lute which materials
zirconia and emax
implication of location of the margin? enamel locatino?
supra-gingival
ideal for scanning
- but more related to bonding
enamel present on all margins – makes digital scanning more ideal condition
- but again it is more related to BONDING
implication of location of the margin? enamel locatino?
supra-gingival
ideal for scanning
- but more related to bonding
enamel present on all margins – makes digital scanning more ideal condition
- but again it is more related to BONDING
access with regard to optimal condition for digital scanning
access– the patient needs to be able to open wide enough to insert the camera in the correct position and the operator needs adequate access in order to accomplish a prep that can be scanned and milled
gingival health with regard to optimal condition for digital scanning
required for all types of fixed restorations
- if using blue cam- we need to use reflective powder, any bleeding from the gingiva will prevent us from powdering properly
have patient clench during a buccal bite registration
NO
- just bring the teeth together
have patient clench during a buccal bite registration
NO
- just bring the teeth together
isolation implication
CRITICAL FOR BOTH CAMERAS
- teeth must be kept dry during the scanning process, with or without the powder
reflection of the saliva?
bad - will cause the omnicam to stop taking pictures
if powder gets wet?
isolation problem - images will look like they are covered with ‘mud’
scan looks like covered in mud
isolation problem
- likely due to saliva / moisture getting the powder wet
scan looks like covered in mud
isolation problem
- likely due to saliva / moisture getting the powder wet
soft tissue managemnt
- WAYS MENTIONED WE USE
MANDATORY
- scalpel
- electrosurgery– PACKING CORD
- laser
linear scanning
recommended techniuque
if well isolated
should NOT take long
do this then if see black areas then go back to those areas only to fill them in
scalpel for soft tissue management
cost efficient but poor hemorrhage control and visibility
second appt. often required
double cord technique
place 0 or double 00 treated cord
cut cord so do not have any cord hanging out of the sulcus
second cord is next size up – and leave a tag of cord out
when ready to impress- remove top cord and be sure that the first cord did not pull out
you NEED to be able to see the WHOLE margin without cord adjacent to the margin
bur size in CAD/CAM
1-1.5
so if angle less than 1mm – bur does NOT cut it - cannot fit – will over mill it - meaning thinner restoration
software will over mill where but not where
over mill irregularities less than 1 mm on axial walls and occlusa lsurface
but will NOT compensate for irregularities all along the margins
over mill on margins?
NO
s- so margin needs to be perfect and crisp and totally smooth
Requirement for cad cam prep - general
ROUNDED
no irregulariteis and spikes
slightly more tappered
- no sharp axial - occlusal angles
- smooth surfaces
- preserve as much enamel at margins as possible
- VERY smooth margins
single important thing for great dentistry?
INEGRITY of the dentist
in terms of procedure – prep is most important
foundation for well fitting durable restoratino
PREPARATION
- spend time required
- use vision magnification to evaluate the prep prior to final optical impression
implction of saving more enamel / minimal prep
bonding!!! - better bonding to enamel
margin type
shoulder or deep shammfer
minimum occlusal reduction
2mm
depth of margin design
1mm
taper on cerec
6-8 is ideal
exit angles for inlays and onlays
90 degree
proximal box shape
- rounded smooth box shape; avoid sharp corners
- walls should taper 6-8 degrees
- avoid undercuts in walls
- smooth floor- rough areas may inhibit seating
- avoid sharp internal angles
spike on margin?
will not cut / compensate and crown WILL NOT SEAT
onlays crown in cerec design
1 . desire 2-2.5 mm reduction over functional cusps and central fissure
- at least 2 mm over non funcitnal
- desire bulk of ceramic at the margin
- avoid sharp internal angle- keep walls smoth
proximal box starting point
line angles
outside - in design
CENTRAL GROOVE
largest cause of ceramic failure
UNDER REDUCTION
must have a minimum of 1.5 of PORCELAIN
if unable to reduce 2mm occlusally, another material must be chosen
note PFM’s require at least 1.5mm reduction for success
if unable to reduce 2mm occlusally?
CHOOSE ANOTHER MATERIAL
EMAX full coverage on posterior reduction?
at occlusal
axial
at margin
occlusal = 1.5 - 2mm
axial = 1.5mm
at margin = 1 mm
rounded internal line angles
flat ended tapered diamond bur is utilized to establish a butt joint margin
minimal ceramic thickness for crowns inlay/onlays
occlusal = 2 mm
axial = 1-1.5 mm
at margin = .8mm – will approach 1 towards axial wall
how do we get the best initial proposal?
- great preps
model axis
set model in the proper place in the horseshoe
- molars in the dots
- premolars in the stripes
SET MIDLINE
SET BOTH OCCLUSAL PLANES AS FLAT AS POSSIBLE
Setting this accuratley
Most important part of what kind of proposal we get initially
is model axis path of insertin?
NO –
T/F can use tools after design has been proposed
true
anatomical tool
two directional
will move 1/3 of the restoration, keeping the anatomy, in the direction the arrow is pointed
multiple areas can be chosen
circular tool
will move area of chosen size, as picked on the size wheel
does NOT MAINTAIN anatomy and will just move selected area
said one he uses the most
setting crown color contacts
blue - we want this
design tips
1-7
turn on or off the minimal thickness icon
TURN ON – first point on the design tips
least ‘important’ step in the CAD/CAM process
most important?
DESIGN = least
most = prep and acquisition
re-calculate button
will bring you back to starting proposal
polishing and glazing with
be sure?
ENAMIC can ONLY BE HAND POLISHED
be sure
- all adjustments have been made
- hand polished using porcelain polishing kit
use all three grits
be very careful that you DO NOT remove proximal contacts
finish with diamond polishing paste on a bristle brush
place enamic glaze if available and light cure
enamic can be only
polished
cannot be fired
mark II at the end
can be hand polished or fired in oven
if needd to add stain then it has to be fired
hand polishing done same as enamic – but no enamic glaze
most natural look
hand polished porcelain
occlusal adjustment with marrk II
HAS TO BE BONDED FIRST THEN OCCLUSAL ADJUSTMENT
emax at end
has to be fired
must be fired in oven in order to convert / crystallize block to go to lithium dislicate
MUST BE fired in oven to glaze and stain
celtra duo at end
gains more strength is fire it
but can be hand polished as well
luting requires a
retentive prep and intimate fit of crown to prep
concepts for cementation
we are BONDING all milled restorations
we are using a dual cure resin cement
we need to bonf the restoration to the cement
we need to bond the tooth to the resin cement
therefore – we need to treat BOTH the intaglio of the restoration and the tooth surface
we are ____ all milled restorations
BONDING
what do we lute
PFM’s and zirconia
all else we are bonding?
etching of milled restorations for Enamic
60 seconds etch with 5% HF
30 seconds wih 9.6 % HF
etching of milled restorations for mark II blocks
(which is feldspathic porcelain)
30 seconds with 9.6% HF
etching of milled restorations for emax
20 seconds with 5% HF
10-15 seconds with 9.6% HF
etching of milled restorations for celtra duo
30 seconds with 5% HF
20 seconds with 9.6% HF
almost same as emax except 5 seconds longer with HF
multi-link instruction he highlighted
NOT HF
using PHOSPHORIC ACID
typical spacing of cement
100 micron space
complete kit of multi-link cement
ivoclean
monobond
self etching primer bottles A and B
multi-link cement in auto mix syringe
have patient bite on bonded restoration
NO
apply pressure until the end
ivoclean use
part of the multi-link kit
clean restoration with this if it has been previously etched
etch restoration with multi-link when
when it HAS NOT BEEN PREVIOUSLY ETCHED
use of monobond
aply this to the INTAGLIO of the restoration for 1 minute – then air dry
