Post on 04-Jul-2020
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Gingival Retraction Key to Successful Impressions
Affects long term gingival aesthetics
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Gingival tissues should be in a state of health prior to starting otherwise struggling right from the start
Effective Gingival Retraction3
Horizontal RetractionNeed for bulk of impression material to pour impression without tearing
Vertical Retraction Must expose margin and see the root surface
Hard Tissues need to be clean and Dry.
Healthy GumsAll bleeding must stop
Must visualise all of the margin
Emergence Profile4
0.5mm-1.0 Horizontal and Vertical Retraction
Gingival Retraction5
Surgical
MechanicalChemical
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Mechanical Retraction Retraction Cord
TWISTED
BRAIDED
KNITTED This is my preference
PLAIN OR IMPREGNATED
How Many Cords Are Needed7
Supra gingival - 0
Veneers - 1
Usually 2 is my gold standard
Crown and Bridge -2 ( or 1)
Margins are usually shallower
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Two Cord Technique- Gold Standard
TWO CORDS USED - THIN FIRST CORD IS PLACED FIRST AND LEFT IN PLACE FOR THE IMPRESSION
SECOND CORD IS REMOVED BEFORE IMPRESSION IS TAKEN
FIRST CORD IS NON MEDICATED 3/0 Black Silk or Ultrapak 000
SECOND CORD USUALLY MEDICATEDMine Ultra Pak 0-1
After Placement of Black Silk/0009
Evaluate Margin Show
Assess amount of retraction still required
Drop Margin if Needed
Refine/Smooth Margin
Gingival Packing Technique10
FORM LOOP WITH CORD
I START IN THE INTER PROXIMAL AREAS FIRST
PACK INTO PREVIOUSLY PACKED AREA
DO NOT USE EXCESSIVE FORCE
PACK SLIGHTLY TOWARDS PREPARATION
WET CORD PRIOR TO REMOVING
1/2 Hollenback
Gingival Packing Instruments11
Use this with my first cord. Need to be GENTLE!
Periodontal ProbePremier angled Serrated
Specialised packing instrumentUse this with my second cord
Rounded tip otherwise pulls out cord
4 MINUTES GIVE MINIMUM 0.2MM SPACE
SOAKED CORD LEAVE NO MORE THAN
5-10 MINUTES
Double Cord Sequence13
Black Cord start inter proximal
Second Cord
Keep Packing
Start inter proximal
Cut Off
Keep Packing
Tuck 1st Cord in
Ends left dangling
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Chemical Retraction Haemostatic Agents
GELS OR SOLUTIONS
ALUMINIUM OR FERRIC SALTS
PRESOAK CORD
TASTE/PH
Chemical- Haemostatic Agents15
Vaso Constrictors
Astringents
Adrenaline- Systemic Effects- Use Local Anaesthetic
Aluminium Chloride
Aluminum Sulfate
Ferric Sulfate
My Haemostatic Agents16
Astringedent
15.5% Ferric Sulfate
VISCOSTAT
10% Ferric Sulfate
Haemodent
5-10% Aluminum Chloride
STYPTIN
20% Aluminium Chloride
Gelcord
25% Aluminium Sulfate
Viscostat Clear
25% Aluminium Chloride
Viscostat vs Astringedent17
Action of Viscostat
A s t r i n g e d e n t i s m o r e a c i d i c (removes dentine plugs)Watch with self etching bonding s y s t e m s - u s e pumice
Polyethers may be affected - Wash
Tissues turn blue with adrenaline and Astringent
Viscostat Viscostat Clear
I use Microbrush on pad
My Use of ViscoStat18
Rubbing Scrub No Bleeding!
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Effect of Haemostatic agents on resin bonding?
CAN HAVE DETRIMENTAL EFFECT WITH SELF ETCHING ADHESIVE SYSTEMS
USE OF CHLORHEX SOL OR AGGRESSIVE CLEANING WITH PUMICE WILL IMPROVE
NO EFFECT WITH ETCH AND RINSE ADHESIVES (GENERATION 4,5)
VARGAS J ESTHET REST DENT 2009 21(2)75-76
Surgical Retraction20
Electrosurge Laser Crown lengtheningRotary
Electrosurge21
Troughing
Remove 0.2-0.5mm junctional epithelium
Don’t touch connective tissue fibres
Use of Electrosurgery22
Must be Grounded
Use of High speed aspiration or orange spray to avoid the smell
Use Plastic Aspirator and Mirror
Type of current usually set to CutUse Coagulation setting if bleeding as well
Power setting should not allow charring/sparking or dragging
May need post operative analgesia
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Tips
‣USE FINGER RESTS
‣PRACTICE STROKE FIRST BEFORE CUTTING
‣NO SPARKING OR DRAGGING
‣SERIES OF SMALLER STROKES
‣LET TISSUE COOL 10-15 SEC BEFORE
RECUTTING
‣CLEAN ELECTRODE ON ALCOHOL SOAKED
GAUZE
‣USE 6% HYDROGEN PEROXIDE AFTER USE
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‣USE GROUND ELECTRODE
‣WATCH WITH OLD PACEMAKERS
‣WATCH USE WITH O2 AND NITROUS
‣USE PLASTIC INSTRUMENTS
‣DON’T TOUCH METALLIC RESTORATIONS/
IMPLANTS
Electrosurge safety
Electrosurge use25
Posterior situations
(occasional)
Thick biotype tissue
Overlapping bits of tissue
over cord
Laser Soft Tissue Retraction26
Epic 10- Biolase
Concentrated beam of energy delivered to tissue via small diameter fibre (200-400
ums). Less destruction
Less pain Improved healing
Single use electrodes
Ilase- Biolase
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Epic 10 - my favourite
SOFT TISSUE TROUGHING, IMPLANT RECOVERY, FRENECTOMY
WHITENING NO SENSITIVITY
PAIN THERAPYTMJs plus other soft tissue
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Lasers - My tips for soft tissue use
TROUGHING ONLY 1MM INTO SULCUS, DON’T TOUCH ATTACHED CONNECTIVE TISSUE FIBRES
SHORT OVERLAPPING STROKES NOT ALL THE WAY AROUND IN SINGLE STROKE TAKE YOUR TIME- NOT AS FAST AS AN ELECTROSURGE
DON’T OVERHEAT TISSUEIF TURNS WHITE IT WILL RECEDE
Surgical RetractionRotary
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Ceramic Bur
Used without water
Used if problems with other techniques
Kerr
Use in High speed
NTI Rotary Tissue Trimmer
Crown Lengthening30
Consider Crown Lengthening if biologic
width violation
PastesExpasyl- Kerr
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Kaolin and Aluminum Chloride
Angle cannula into sulcus
Get right angle Watch for Whitening of gingiva
Leave for 1-2min 3-4min for thick tissue
Rinse
Expazen - NewCord paste from Acteon/Kerr
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3M ESPE Astringent Paste33
85% Fillers, water, modifiers
15% Aluminium chloride hexahydrate
3M ESPE Astringent Retraction Paste
The 3M Astringent Retraction Paste fits into common composite dispensers. Extrude a small amount and discard.
Move around the tooth with inserted tip while slowly and steadily, inject astringent retraction paste into the sulcus. Completely fill the sulcus.
Optional procedure: For more gingival deflection, the astringent retraction paste can be used in combination with retraction cords.
Leave astringent retraction paste on for a minimum of 2 minutes.
Completely remove astringent retraction paste with air-water spray and suction.
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Polymers and Pastes- My Take
TECHNIQUE SENSITIVE
VARIABLE UNPREDICTABLE RESULTS
STILL MAY NEED TO USE CORD
HAS ITS PLACE IN CERTAIN SITUATIONS- ESPECIALLY ANTERIOR
VENEERS & THIN BIOTYPE
What are clinician’s doing now?38
Clinicians Report Page 3 March 2015
Foolproof Techniques for Optimum Impressions (Continued from page 2)
Achieving the Perfect ImpressionA. Tissue Management: Use 0.12% chlorhexidine gluconate (Peridex or others) for 6 weeks to achieve pink, healthy tissue (2 weeks pre-operatively, 2
weeks during provisionalization, and 2 weeks post-operatively). Be gentle to soft tissue during preparation, fabricate well fitting provisionals and havepatient practice good oral hygiene. Chlorhexidine gluconate rinse is especially useful for multi-unit cases.
B. Retraction Techniques1. Two Cord: Recommended technique.2. One Cord: Unpredictable bleeding when cord is removed.3. No Cord: Inability to capture margins at or below gingiva.4. Laser/Electrosurgery: Careful use can be acceptable. However, troughing of tissue
around tooth can produce unpredictable tissue response.5. Retraction Paste: Can augment other procedures, but is unpredictable when used alone.
C. Tray Selection1. Double Arch Impression Tray: Well proven for 1–2 units. Saves time by
eliminating interocclusal record and opposing cast. 2. Custom Trays: For 3 or more units. Very stable and accurate. Uses a smaller
amount of impression material (up to 2/3 less material). Tray should haveadequate stops in non-relieved areas to provide solid seat.
3. Stock Trays: Can be acceptable if used properly. Most commonly used. Tray fitis often inadequate. Requires more impression material than custom tray.
D. Requirements of a Double Arch Impression Technique1. Acceptable pre-operative occlusion. Equilibrate and remove any objectionable disharmonies.2. Impression includes canine and tray does not contact tooth structure.3. Sideless tray reduces distortion.4. Thin, non-water absorbent interocclusal wafer.5. Thin distal connector, allows ability to close down completely.6. Can be rigid or flexible.
E. Current Impression Materials are among the best materials in dentistry1. VPS (vinyl polysiloxane): (examples: Affinis by Coltene, Aquasil Ultra by Dentsply,
Correct by Pentron, Examix or Exafast NDS by GC America, Imprint 3 or 4 by3M ESPE, Take 1 Advanced by Kerr, and many others)
• Most popular, brands are more similar than different • Long-term stability• Excellent accuracy and elastic recovery • Neutral taste/odor• Easily removed and can be disinfected • Sensitive to latex (sulfur) contamination
2. Polyether: (examples: Impregum and Permadyne by 3M ESPE; and Polyjel by DentsplyCaulk)
• Excellent accuracy and near perfect surface detail reproduction• Most hydrophilic elastomer• Snap set: Does not start setting until end of working time, then sets immediately, unlike VPS gradual set• Short-term stability (2 weeks) and moderate to poor elastic recovery• Not sensitive to latex (sulfur) contamination, but disinfection can cause distortion
When to Use VPS or Polyether Impression Material• One or two units with undercuts: VPS• One or two units with no undercuts: Either• Multiple units with undercuts and non-parallel teeth: VPS• Multiple units with no undercuts: Either• Ability to disinfect: VPS• Difficult moisture control: Polyether
TIP: Faster VPS MaterialsThe trend of the newer VPS impression materials is toward speedand improved hydrophilicity (Aquasil Ultra Super Fast by Dentsply,Exafast NDS by GC America, First Quarter VPS by Danville, Imprint 4by 3M ESPE). Intraoral time for Super Quick Imprint 4 is 75seconds. With any of these fast-setting materials, the temperatureof the mouth accelerates the set. Have the assistant load the heavybody material into the tray first. The dentist then syringes the washmaterial into place. The pre-loaded tray is then insertedimmediately into the mouth and allowed to push the wash intoplace before the temperature accelerates the set of the material.See Clinicians Report July 2014.
Top Products for Optimum Impressions• Sideless Posterior Triple Tray, Premier: Flexible double arch impression tray that is best with rigid tray material.• Quad-Tray Xtreme, Clinicians Choice: Rigid double arch impression tray can be used with flexible or rigid tray material.• Triad 2000 Light Cure System, Dentsply: System allows fast and easy fabrication of custom trays. Example product for system is TruTray.• Pentamix 3, 3M ESPE: Automated mixing and dispensing system for impression materials. Smaller size unit requires placement in central
location. Easy to use, homogenous mix, limits waste, and reduces infection control concerns. Used primarily for tray material (heavy body, monophase).• Roeko Comprecap, Coltene: Cotton compression cap placed over the tooth and the patient instructed to bite down. Controls moisture and
bleeding and facilitates retraction. Can be used over 2nd cord or with retraction paste. Does not adapt to all teeth.• Zekrya Gingival Protector, DMG America: Instrument with metal handle and replaceable crescent shaped metal tip. Used to retract and protect
gingiva while finishing margins. Especially useful in the anterior region. • Roeko Stay-Put Retraction Cord, Coltene: Braided cord with copper wire filament that keeps the cord in place around the tooth. Non-
impregnated or impregnated with aluminum chloride. Ideal for use as 2nd cord. • ViscoStat, Ultradent: Potent styptic for hemostasis. 20% ferric sulfate applied directly to tissue with infuser tips or dipped in 2nd cord. Potential
staining issue limits use to opaque crowns (PFM, gold alloy).• ViscoStat Clear, Ultradent: 25% aluminum chloride for hemostasis. Although not as potent, it is applied in similar fashion to ferric sulfate. It can
be used with translucent crowns (lithium disilicate).• Directed Flow Impression Tray, 3M ESPE: Innovative full arch stock tray that requires no adhesive (self-retentive fleece strip)• Kwik, Cosmedent: Very fast setting tray adhesive for VPS impressions that dries in 1 minute instead of the usual 10 minutes for most VPS adhesives.
39% Two Cords 25% One Cord 16% Other 12% Retraction Paste 8% One Cord and Retraction Paste
CR Survey: most common method of tissue management and retraction
39%
25%
16%
12%
8%
Sideless Triple TrayPremier
Quad-Tray XtremeClinicians Choice
These trays meet the optimum requirements for a double arch tray for 1–2 units
CRA MARCH 2015
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IMPRESSION TAKING
Perfect impressionsConsistently, Predictably Every time
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Tray use survey trendsCRA March 2015
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60% use triple tray for multiple units
21% use special tray for multiple units More dentists should use to save money and improve accuracy
68% use triple trays for single units
60%
21%
68%
SPECIAL TRAYS42
EVEN THICKNESS OF MATERIAL (2-4 MM) THEREFORE MORE ACCURATE IMPRESSION
ALLOWS SAVING IN AMOUNT OF MATERIAL USED (2/3RDS LESS
MATERIAL)
NEEDS TWO VISITS - TIME FOR SET OF TRAY
MUST BE DESIGNED TO RETAIN MATERIAL- PERFORATIONS, ADHESIVE
CHEMICAL CURED TRAYS
SPECIAL TRAYS43
THIS IS WHAT WE USE NOW NO PROBLEMS WITH MOVEMENT
5-10 MINUTES TO MAKE
LIGHT CURED TRAYSAS CHEAP AS $200
YOUR NURSES CAN DO THIS!
LIGHT OVENNEED TO LET IT SET FOR A DAY
CONTACT DERMATITIS POSSIBILITY SMELLS
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Tray Adhesives
USE ADHESIVE SPECIFIC FOR CLASS OF IMPRESSION MATERIAL
SINGLE LAYER
PAINT AT LEAST 5-10 MINUTES BEFORE IMPRESSION (SILICONE)
FOR POLYETHER 90 SEC
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Triple Tray/Double Arch Tray
‣CAN BE USED WITH INTACT DENTITION
‣SHOULD HAVE NATURAL CANINE AND
ANTERIOR GUIDANCE
‣FOR 1-2 CROWNS
‣PATIENT SHOULD BE ABLE TO CLOSE INTO
CENTRIC OCCLUSION
‣NEED GOOD LAB SUPPORT
These days Quadrant impressions in Digital46
Quadrant scan
Quadrant Printed Model
IMPRESSION MATERIAL USECRA MARCH 2015
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Polyether48
Moisture control not as critical
Hydrophilic
Generally 3 minute set
Short Setting time
Excellent accuracy and near perfect surface detail reproduction
Can pour up easilyLow surface tension
If not using Duosoft, can extract teeth!Rigid
Lose and gain moisture, pour within 2 weeks
Imbibition
Snap set
Short working time
Long teeth, isolated teeth, reinforce with wire
Model preparation Problems
Advantages Disadvantages
This is my favoured material for any removable prosthodontics
Full, Partial or Implant over dentures Generally do a mono phase impression here
PolyEther49
Impregum Duo SoftAddition Silicones
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Dimensionally Stable and excellent accuracy
Multiple Pours, long term stability
Good tear resistance
Water Friendly
High surface tension
Hydrophobic?
Advantages Disadvantages
Neutral Taste and Odour
Addition Silicone Techniques51
Putty Wash
Heavy LightMonophase/Single body
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Putty Wash Technique
ONE STAGEPUTTY WASH RECORDED TOGETHER
TWO STEP SPACED 2 MM SPACING RECOMMENDED USE TEMPORARY CROWN
TWO STEP UNSPACED POTENTIAL FOR INACCURACIES
Problems with One Step Putty Wash Technique
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402 BRITISH DENTAL JOURNAL VOLUME 191 NO. 7 OCTOBER 13 2001
DENTAL KNOW HOW
Q. What are the steps in achieving a successful impression?A. There are several key factors in obtaining a good impression:• Prepare the soft tissues• Select an impression technique• Select an impression material• The impression recording procedure
Q. How can I prepare the soft tissues?A. Aim for:• Good soft tissue health beforehand• Ensure that the preparation margin is visible, perhaps best
achieved by recontouring the gingival margin using electro-surgery.
• Placing margins supragingivally is an advantage but wherethis is not desirable then retraction cord can be used.
Q. Which impression technique should I consider?A. The choice is usually between putty/wash, dual-phase(heavy and light) or monophase.
The majority of UK dentists use a one-stage putty-wash tech-nique with the advantages of simplicity, reasonable economy,predictability and dimensional accuracy1 as well as speed,particularly when a fast set material is used. Selection of ametal or rigid tray allows for greater accuracy.2
What typically happens (see Fig. la,b) is the putty tends topush the light body wash off the prepared tooth. The washmaterial then ends up in the lingual or buccal sulcus and the
critical areas, such as preparation margins, may be recordedwith putty which cannot record detail as well as the washmaterial. This is a particular problem where the preparationmargin is towards the occlusal surface of the tooth, eg inlays,onlays, 3/4 crowns, porcelain veneers, resin bonded bridges.
Another difficulty with the technique is that once the lightbody is on the preparation the putty needs to be brought intoposition and seated. During this critical phase the patient maybring their tongue or floor of the mouth close to the teeth andremove the light-body material from the tooth. This can be aproblem with the lingual aspect of lower molar teeth.
Q. So what are the alternative techniques to overcome theseproblems?A. One method is to record the putty-wash impression in twosteps of which there are several options:
Putty then wash as two separate stagesIt is useful to record the putty before preparing the tooth. Thiswill give some space for the wash material around the prepa-ration otherwise there may be distortion of the putty or tray asthe wash material is compressed. Figure 2 shows an exampleof a two-stage putty wash.
The disadvantages of this two-stage technique include theadditional time of having to wait for two materials to set, cont-amination of the putty with saliva which may prevent lightbody adhering to it, and difficulty in reseating the set putty inthe mouth.
Sluices are usually cut into the putty running away from theprepared tooth regions. A scalpel can be used to cut V-shapedsluices but a putty knife makes the job quick and easy (Fig. 3).The sluices allow for excess material to escape. If necessary
How to make a good impression (crown and bridge)Brian Millar BDS, FDSRCS, PhD, Senior Lecturer, Consultant in Restorative Dentistry, Departmentof Conservative Dentistry, GKT Dental Institute, King’s College London
SPONSORED BY AN EDUCATIONAL GRANT FROM
Fig. 1a,b Typical one-stage putty washimpressions illustrating howthe putty pushes the lightbody off the preparations,including key areas such asthe margins of preparations
Fig. 2 A two-stage putty wash impression with the samematerials as in Fig. 1b
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02
03
Movement of light body away from margin and critical areas
Putty ability to capture detail not as good
Particular problems with prep margin near occlusal surfaces like for inlays, veneers, resin bonded bridges
Millar BDJ 2001 191(7)12-14
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This is my preferred technique
Heavy/Light Impresion technique
Heavy Body in tray
Light body in syringeUse for majority of time
Medium Body in syringe Usually where more viscosity is required or around implants
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What about fast set Materials
Good for 1-2 teeth
Know your set and working times Imprint 3 Imprint 4
Load impression tray before syringe Light body must not start to set before heavy body is inserted
Range of setting times 1:30-2:30
Imprint 3 vs 4I still use Imprint 2
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Normal Crown and bridge
Material Types57
Medium and HeavyImplant head impressions
Light/Medium/Heavy Light and Heavy
Mixture- implant and crownsLight and Heavy I like using these
Coe SyringeI don’t think this allows you to see what tip is doing as well
Syringe tips on Cartridge
Impression Syringes/Tips58
More tactile feel Get closer to the preparation
Nurse cover tip when passing
Cut tip if needed to increase opening
Use of syringe59
Syringe use tips60
Syringe tip on margin at all times
• Cushion material before syringe
tip into marginal area
• If can’t get through, access
material from other side before
injecting
• Dry run with syringe or tip to
ensure access to all parts of
tooth
Ready/Set/Go61
Nurse has paper towel and mirror ready
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BLOW OR NOTI like to blow after placement of light body
THIS IS NOT TO ‘PUSH’ IMPRESSION MATERIAL INTO SULCUS BUT TO REDUCE SURFACE TENSION
IF MATERIAL BLOWS OFF, PREP IS TOO WETBlow dry and inject again
ONCE MATERIAL STAYS ON, INJECT FINAL WASH MATERIAL LAYER AND PLACE TRAY WITH HEAVY BODY
INJECT-BLOW-INJECT TECHNIQUE
New Impression Syringe3M Espe
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Syringes for both PVS and Polyether Clip onto cartridge Fill
Place plunger Can stay for a few days Compares sizes of different options
Fabricating an Ideal Impression
RetractorsMy Second Pair of Hands
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Use these for most of my impressions Generally around $15 each, Autoclavable
Livingstone
Indispensable
These have handles at sidesKerr Retractors
Very good for also for Photography
Block out undercutsUnder bridges, implants, perio involved teeth
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Blue periphery wax Oraseal
Block out undercuts
Clinical Tip67
Don’t you hate half wasted tubes
ExtendersFrom Adam Dental
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Extender Place on Cartridge Join to other cartridge
Inject into one cartridge Clean up with q tip Ready to go again
Evaluation of an adequate impression69
Coverage, tears, dragsOther teeth
Adhesion of material to each other/trayMaterial consistency
General
Preparation
01
02
03
Emergence profile- length/width 04
05
Material consistency
Margin quality Preparation quality
Bubbles, drags, tears
Bleeding-what now?
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Bleeding - what now?
USE STRONGER HAEMOSTATIC AGENT
USE TWO CORD TECHNIQUE
USE ELECTROSURGE ON COAGULATION CYCLE
USE MORE HYDROPHILIC IMPRESSION MATERIAL
BLOW BLOOD AWAY AND GO FOR IT!
TAKE SECOND IMPRESSION
STOP, RETEMPORISE, REIMPRESS AFTER HEALING PERIOD (PAT ON M WASH)
Bubbles - where are they important?72
Generally a result of inadequate syringing
technique
Contamination with blood/saliva/gingival
fluids
Impression Troubleshooting Guide
3M Oral Care
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What about the elephant in the room- Digital Impressions?
Did my Masters thesis on CEREC 2 in 1992
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Co Inventor of CEREC University of Zurich
Werner Mormann
I was one of the first in Australia to research CAD/CAM
Francois Duret- early pioneer
My History With Digital Cad Cam
Looked at marginal accuracy of CAD/CAM onlays, laboratory and pressed
onlays
How many of you have done anything to do with Digital
dentistry?
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More pervasive than you think77
What is possible with Digital Impressions?78
Crowns/Bridges Veneers/Onlays Dentures
Temporaries Post and cores Implant surgical guides
Splints Implants abutments Orthodontics/Invisalign
Shade taking79
Why go digital?80
SAVE TIME
SAVE COSTS - IMPRESSIONS
DECREASED TURNAROUND TIME
DIGITAL ACCURACY
IMPROVED PATIENT COMFORT/EXPERIENCE
ENJOY IMPRESSION TAKING
DIGITAL RECORDS
One big reason for usStorage room
81
Getting Into Digital impressions?82
Do you just want to Scan
Do you want to construct restorations as well
CAD/CAM systems- Integrated systems83
Long history Now no powder with omnicam
$185000
CEREC
Scan and milled at same appointment More expensive
Long history Needs enough time in workflow
In office, closed systems
E4D- larger mill, no powder
3M Tru Def
Digital impressioning Systems84
No powder Around $45000
Trios 3 ScannerPowderless - No Annual Fees, Open system
around $39000 ?
Carestream 3600Needs light coating of powder
$35000, View in 3D
85
TRIOS® Pod – The Mobile
• Small footprint • Extreme mobility • Connect to multiple laptops / PCs
We had to confirm its accuracy I am a prosthodontist after all!!!
86
Did both conventional and digital and made 2 crowns Both crowns were interchangeable on the models
Digital Crown had better fit and contacts! and was inserted
We have had our scanner for only 6 months87
Digital impression with model88
Digital Impression without Models89
Model or No Model 90
Title Goes Here Title Goes Here
More familiar process for Laboratory and you. Best start off this way until get familiar
Model
There are many 3D printing services of different abilities ?Milled models
Accuracy of Model
Trust in Digital process! Chipping of margins possible Restorations generally designed oversized
Modelless
If need to add to porcelain in anyway will need modelBest for Full contour restorations
This is a Paradigm shift91
Retrain yourself to visualise marginsNeed to look at scans carefully
Can see emergence profile if scan is ‘flipped over’
Emergence profile
‘Green’ AreasWhere insufficient information is present
92
My first scan took over 1 hour!
Need to decide what is critical ‘We are Green Friendly’
Digital and gingival retraction93
Digital will not hide bad preparations or poor
retraction or see through blood!
I am generally using a larger second cord to
improve horizontal retraction
Can erase parts of the margin and rescan if
neededBite registration
Great things about Digital Scans94
Automatic checkCheck for clearance Check for undercuts
can manual registration as well
If you decide to get into restoration as wellNumerous wet/dry/combined mills present - Learn to ‘walk’ first!
95
VHF N4
Full integration
CORiTEC 140i
Full integration In clinical use
DWX-4W
Full integration
LYRA Mill
Full integration In clinical use
Arctica
STL Interface In clinical use
PlanMill 40
Full Integration In clinical use
My initial impressions with digital after 6 months96
There is a learning curve for you, your staff and your labs Give yourself enough time in your first cases Work to make it fit into your workflow There is a technique to scanning You don’t need to get every little ‘green’ areas only the important ones Digital technology brings its own challenges which companies don’t talk about Take your time in deciding the right system for you Pick a sales vendor which will offer you support
97
“These are exciting times”
(How did you do in the budget?!!)