1

Gingival Retraction Key to Successful Impressions

Affects long term gingival aesthetics

2

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

6

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

8

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

14

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!

19

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

23

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

24

‣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

27

Epic 10 - my favourite

SOFT TISSUE TROUGHING, IMPLANT RECOVERY, FRENECTOMY

WHITENING NO SENSITIVITY

PAIN THERAPYTMJs plus other soft tissue

28

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

29

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

31

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

32

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.

37

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

39

IMPRESSION TAKING

Perfect impressionsConsistently, Predictably Every time

40

Tray use survey trendsCRA March 2015

41

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

44

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

45

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

47

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

50

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

52

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

53

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

01

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

54

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

55

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

56

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

62

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

63

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

65

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

66

Blue periphery wax Oraseal

Block out undercuts

Clinical Tip67

Don’t you hate half wasted tubes

ExtendersFrom Adam Dental

68

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?

71

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

74

What about the elephant in the room- Digital Impressions?

Did my Masters thesis on CEREC 2 in 1992

75

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?

76

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?!!)