CAD CAM –IN FIXED CAD CAM –IN FIXED PROSTHODONTICSPROSTHODONTICS

Gudance;Dr.M.Vasanthakumar H.O.D, Dr.B.Muthu kumar,Professor

Presenter: .Dr.G..Uday Raghav Reddy

CHANGING LIFE STYLECHANGING LIFE STYLE;; Instant food, instant messages ,internet, Instant food, instant messages ,internet,

chatting, all these were unknown to chatting, all these were unknown to common man few decades back and common man few decades back and today they are into our lives where we cant today they are into our lives where we cant expect to live a day without using mobile expect to live a day without using mobile or other gadgets.or other gadgets.

Speed,Speed, instant,instant, ImmediateImmediate

are the buzz words of modern era.are the buzz words of modern era. As we all are aware today in this 21st As we all are aware today in this 21st

century, with the technological century, with the technological advancements in the fields of electronics & advancements in the fields of electronics & communications just with a click of button communications just with a click of button we can have access to the world. we can have access to the world.

Technologies also made Technologies also made its way into dental and its way into dental and medical fields and have medical fields and have changed the face of changed the face of treatment modalities jn a treatment modalities jn a given situation be it given situation be it partial or complete partial or complete denture prosthodontics.denture prosthodontics.

It is highly essential for us It is highly essential for us

to quickly accept and to quickly accept and adapt to these new adapt to these new concepts with a little concepts with a little caution.caution.

One such technology which is claiming to One such technology which is claiming to be more precise, easy to learn and be more precise, easy to learn and constantly undergoing research is CAD constantly undergoing research is CAD CAM technology .CAM technology .

SET BACKS OF CONVENTIONAL SET BACKS OF CONVENTIONAL METHOD METHOD

Requires many clinical and laboratory steps Requires many clinical and laboratory steps following tooth preparation such asfollowing tooth preparation such as : :

impression making with gingival retractionimpression making with gingival retraction die preparation,die preparation, wax pattern fabrication,wax pattern fabrication, investing,investing, casting by means of lost wax process,casting by means of lost wax process, trimming finishing,ceramming etc trimming finishing,ceramming etc

After performing all the above mentioned After performing all the above mentioned methods with great caution, there is no methods with great caution, there is no guaranty that we get a prostheses with guaranty that we get a prostheses with accurate fit between the restoration and accurate fit between the restoration and prepared tooth. Inprepared tooth. In addition we may addition we may encounter with casting imperfections such as encounter with casting imperfections such as porosities,impurities,poor soldered porosities,impurities,poor soldered joints,undimensioned, non homogenous joints,undimensioned, non homogenous frame works. frame works.

In a study made by X ray defectography it In a study made by X ray defectography it has been found that one third of all cast has been found that one third of all cast restorations tested were with restorations tested were with manufacturing related deficiencies.manufacturing related deficiencies.

So in an attempt to overcome these So in an attempt to overcome these difficulties CAD CAM technology was tried difficulties CAD CAM technology was tried as early as 1971 first by French and Swiss as early as 1971 first by French and Swiss and later improved a lot till date.and later improved a lot till date.

One purpose-

Rehabilitation of missing teeth

different techniques and materials to fabricate.

Evolutions and revolutions are Evolutions and revolutions are not new to dentistry.not new to dentistry.

Evolution of CAD CAMEvolution of CAD CAM: :

Just like Doctors getting married to Just like Doctors getting married to engineers ,engineers ,may be prosperous ,may be prosperous ,aiming at a aiming at a common goal of common goal of integrating engineering integrating engineering applications of automation in applications of automation in creating of a dentalcreating of a dental prostheses prostheses 3 groups paved the way for CAD 3 groups paved the way for CAD CAM APPLICATIONS in dentistry.CAM APPLICATIONS in dentistry.

French systemFrench system laser scannerlaser scanner Hand held optical probe Hand held optical probe

has a resolution of 20 umhas a resolution of 20 um The probe is passed over The probe is passed over

the area to be scanned 3-4 the area to be scanned 3-4 timestimes

The obtained data is The obtained data is converted into a digital converted into a digital signal and relayed to the signal and relayed to the computer.computer.

Using this data the CAD Using this data the CAD CAM generates a CAM generates a prostheses to fit unique prostheses to fit unique requirement of being requirement of being treated.treated.

SWISS SYSTEM:SWISS SYSTEM:

porcelain inlay( Zurich 1986)porcelain inlay( Zurich 1986) Uses optical topographic scanning system& Uses optical topographic scanning system&

electronically controlled milling machine.electronically controlled milling machine. A 3-dimension intra oral camera is used to A 3-dimension intra oral camera is used to

feed data to an interactive CAD.feed data to an interactive CAD. Inlays are machined from prefabricated rod Inlays are machined from prefabricated rod

shaped blanks of porcelain with a milling shaped blanks of porcelain with a milling machine machine

MINNESOTA SYSTEMMINNESOTA SYSTEM

:Capable of milling a metal :Capable of milling a metal full coverage crowns, frame full coverage crowns, frame work for partial denture, work for partial denture, complete denture bases complete denture bases and bridges.and bridges.

Data are acquired by Data are acquired by photographic based photographic based system.system.

The tooth is illuminated The tooth is illuminated with fiber optics. The with fiber optics. The images are recorded on a images are recorded on a standard film which can be standard film which can be developed by a commercial developed by a commercial processor. A digitizing processor. A digitizing system is also used.system is also used.

CAD CAM_ALL CERAMICSCAD CAM_ALL CERAMICS

CEREC SYSTEM: CEREC SYSTEM: Introduced in mid-1990sIntroduced in mid-1990s Equipment consists of a computer integrated Equipment consists of a computer integrated

imaging and milling system, with restorations imaging and milling system, with restorations designed on computer screen designed on computer screen

Developed by Mormann & brandeesteni (1989)

Morman et.al have developed technical

and clinical concept.

CEREC unit-1: uses a miniature video camera to take picturesof prepared cavity.

.

During the process a grid is projected on to tooth surface.A 3-dimensional picture of tooth is then calculated on basis of distortion of grid.Borders has to be drawn manually .Subsequently the dimensions of restoration are calculated and milled into ceramic block

CEREC-2 unit;Improved software offers fabrication of crowns in

addition to inlays, onlays, veneers,.

Occlusal morphology is achieved by either by

extrapolation/ correlation. (Eliminates the need

for time consuming grinding.

Requires only minor adjustments and polish to complete the restoration

CEREC_3;CEREC_3; More technical improved in More technical improved in terms of image capturing, processing, terms of image capturing, processing, milling.milling.

SEM SEM studies have shown crowns studies have shown crowns fabricared by CEREC 3 has improved fabricared by CEREC 3 has improved margin quality and minimum delamination.margin quality and minimum delamination.

3 materials can be used with this system3 materials can be used with this system

3 materials can be used with this 3 materials can be used with this systemsystem

1) VITA mark ii1) VITA mark ii..22) Dicor MGC) Dicor MGC 3)Pro CAD3)Pro CAD

VITA mark IIVITA mark II

Contains fine particles of feldspar with Contains fine particles of feldspar with albit.albit.

It can resists fracture load of 1800 N.It can resists fracture load of 1800 N.Easy to machine,estheticall pleasing.Easy to machine,estheticall pleasing. Its drawbacks are it is suitable only in Its drawbacks are it is suitable only in

premolar region stability cannot be premolar region stability cannot be achieved.achieved.

Dicor MGCDicor MGC

It is a mica based machinable glass It is a mica based machinable glass ceramic contains 70 volume percent of ceramic contains 70 volume percent of crystalline phase. It s unique House of crystalline phase. It s unique House of cards micro structure is due to interlocking cards micro structure is due to interlocking of small platelet shaped mica crystals of 1-of small platelet shaped mica crystals of 1-2 um.multiple crack deflections & ensures 2 um.multiple crack deflections & ensures greater strength than Lucite containing greater strength than Lucite containing ceramics.ceramics.

Pro CAD:Pro CAD:

it is a leucite containing ceramic design it is a leucite containing ceramic design making machined restorations.making machined restorations.

It has good stability, esthetics .It has good stability, esthetics .Can be accurately milled and ground as a Can be accurately milled and ground as a

result of small uniform size of crystalline.result of small uniform size of crystalline. It s drawback is crowns require glazing for It s drawback is crowns require glazing for

stability.stability.

STEPSSTEPS

Image the preparation with optical scanner, align path Image the preparation with optical scanner, align path of insertion of restoration& best view is saved in of insertion of restoration& best view is saved in computer.computer.

Identify and mark the margins.Identify and mark the margins. Insert the appropriate shade of ceramic block in Insert the appropriate shade of ceramic block in

milling machinemilling machine Fabrcation time for a crown is about 20 min.Fabrcation time for a crown is about 20 min. Additional characterization is achieved with stains.Additional characterization is achieved with stains. Try in mouth, etch and silanate.Try in mouth, etch and silanate.

CELAY SystemCELAY System

it uses a copy milling it uses a copy milling technique to manufacture technique to manufacture ceramic inlays & on lays.ceramic inlays & on lays.

A resin pattern is A resin pattern is fabricated directly on a fabricated directly on a prepared tooth/ master prepared tooth/ master die & the pattern is used die & the pattern is used for milling.for milling.

Marginal accuracy is Marginal accuracy is better than CEREC II.better than CEREC II.

PROCERA ALL CERAMICSPROCERA ALL CERAMICS

This system involves industrial CADCAM processThis system involves industrial CADCAM processThe die is mechanically scanned by technician & data is The die is mechanically scanned by technician & data is sent to a work station where an enlarged die is milled using sent to a work station where an enlarged die is milled using computer guided milling machine. The enlargement is computer guided milling machine. The enlargement is necessary to compensate for sintering shrinkage. Aluminum necessary to compensate for sintering shrinkage. Aluminum oxide powder is compacted on die and coping is milled. The oxide powder is compacted on die and coping is milled. The coping is further veneered with an aluminous ceramic with coping is further veneered with an aluminous ceramic with matched thermal expansion.matched thermal expansion.Advantages; Good clinical performance,& marginal Advantages; Good clinical performance,& marginal adaptation provided scanning is done skillfully. may be adaptation provided scanning is done skillfully. may be suitable for posterior crowns and FPDssuitable for posterior crowns and FPDs

3M ESPE All- ceramic system3M ESPE All- ceramic system A newer dimensionA newer dimension This is a high strength This is a high strength

Zirconia system which Zirconia system which can be utilized to create can be utilized to create all ceramic crowns and all ceramic crowns and FPDs.FPDs.

In the past few In the past few years ,partially stabilized years ,partially stabilized zirconium has been zirconium has been integrated into restorative integrated into restorative dentistry and has wide dentistry and has wide variety of applications:variety of applications:

Frame works for FPDsFrame works for FPDsAs abutments for implant prostheticsAs abutments for implant prosthetics ImplantImplantStock dowel patterns,as orthodontic Stock dowel patterns,as orthodontic

bracketsbracketsZirconia is stabilized with yttrium oxide & Zirconia is stabilized with yttrium oxide &

as yttria-tetragonal zirconia poly crystals as yttria-tetragonal zirconia poly crystals room temperature. room temperature.

The Y-TZP is characterized with high The Y-TZP is characterized with high fracture toughness. When cracks fracture toughness. When cracks appeared due to wear on ceramic, a appeared due to wear on ceramic, a physical effect referred to as physical effect referred to as transformation toughening, served to transformation toughening, served to prevent crack from spreading in ceramic.prevent crack from spreading in ceramic.

Advantages; Advantages; Clinically acceptable Clinically acceptable marginal fit, esthetic marginal fit, esthetic (opalescence,transluscencs)(opalescence,transluscencs)

High degree of homogeneity & good High degree of homogeneity & good surface properties.surface properties.

COMET System:COMET System:

Co-ordinate measuring techniqueCo-ordinate measuring technique steinbcher optotechnik gmbh ,germanysteinbcher optotechnik gmbh ,germany

-ALLOWS THE GENERATION OF A 3--ALLOWS THE GENERATION OF A 3-DIMENSIONAL DATA RECORD FOR DIMENSIONAL DATA RECORD FOR EACH SUPERSTRUCTURE WITH EACH SUPERSTRUCTURE WITH WITHOUT THE USE OF WAX PATTERN.WITHOUT THE USE OF WAX PATTERN.

As in conventional system this uses a stone dies As in conventional system this uses a stone dies fabricated from impression.fabricated from impression.

3 :!)digitizing data from die surface wax pattern3 :!)digitizing data from die surface wax pattern 2)Mathematical processing of data to 2)Mathematical processing of data to

program milling systemprogram milling system 3)Milling3)Milling This machine allows generation of various This machine allows generation of various

restorations from any materal used in restorative restorations from any materal used in restorative dentistry.dentistry.

::

CICERO CAD CAM SYSTEM:CICERO CAD CAM SYSTEM: This system eliminates This system eliminates

the need for correction of the need for correction of occlusal discrepancies A occlusal discrepancies A new device String new device String condylo comp has been condylo comp has been developed that are likely developed that are likely required for a prostheses required for a prostheses fabricated by lost wax fabricated by lost wax process, at the time of process, at the time of delivery which will delivery which will hamper the quality of hamper the quality of restoration especially restoration especially when porcelain is used when porcelain is used on occlusal surface on occlusal surface

This system uses This system uses various input various input parameters to design a parameters to design a functional restoration by functional restoration by simulating 3-D maxillo-simulating 3-D maxillo-mandibular movement mandibular movement patterns on basis of patterns on basis of protrusive,laterotrusve,aprotrusive,laterotrusve,and mediotrusive nd mediotrusive pathways of inter pathways of inter occlusal contact occlusal contact movement. movement.

A newA new opto electronic registration opto electronic registration apparatus String condylo compapparatus String condylo comp has has been developed for clinical purpose.This is been developed for clinical purpose.This is attatched to moving head so the co-attatched to moving head so the co-ordates of relative of mandibular inter ordates of relative of mandibular inter condylar axis are relative to position of condylar axis are relative to position of head.head.

Disadvantage: Time consuming.Disadvantage: Time consuming.

Role of CAD CAM in Implant Prosthodontics

:Dental implants have gained wide

popularity in the past few years because of increased enthusiasm among the

professionals, increased patients acceptance due to the comfort they offer and marketing strategies. Irrespective of

the system of implants, an accurate diagnosis and treatment plan is required

to ensure success.

With advent of improved imaging methods like CT scan (invented by Sir Hounsfield, 1972) has enabled to visualize topographic sections of required area to be worked. The utility of CT for dental purpose started in 1980s.

However access to this information required a radiologist to communicate with referral doctors in detail about prospective surgery and then sit at imaging computer or work station for a considerable length of time to reformat the study, interpret the resulting images, and produce hard copy images. Such technique is usually referred to as Dentascan

Limitations of Denta scan: Images may not be true size and require

compensation for magnification.Determination of bone quality requires

use of an imaging computer.Usually a diagnostic template is required to take full advantage of the technique.

This enables the dentist to incorporate a 3-D treatment plan of final prosthetic result into imaging examination. This

diagnostic template can be made using a number of CAD/CAM procedures.

.

CAD/CAM can produce accurate 3- dimensional models of the patients alveolar anatomy .To plan implant positions and orientations into model, the dentist must also produce internal architecture .

A sterotactic template derived from such model will accommodate pilot drill, and produce a vacuform template that fits to patients bony anatomy and supports the position and orientation of guide cylinders., which reproduce the position and orientation of proposed implants

Dental products report Aug-2005 survey- A Comparison with other modes of fabrication.

PFM s still rule the roost. Their dominance still can be attributed to strength, longevity and function and

adequate esthetics over prolonged usage.

In this survey ; PFM --- 90% Metal Free 40% CAD CAM 9%

WHERE DOES CAD CAM STANDS ?

Eliminates the need for impressions, temporaries and multiple office visits Patient issues of temporaries falling

during interviews / at dinner are no longer a concern.

Key benefits

Review of literature:

Reliability of crowns fabricated by CAD CAM: In a study made by Kunzelmanreliability of Cerec-2 is higher than lab fabricated ceramic crowns.

Wear of clinical crowns during clinical usage Pro CAD and dental enamel behaved same wear and tear.

Fracture resistance of CAD CAM was compared to natural teeth .On applying load along longitudinal axis, using Universal testing machine bothNatural teeth and vita mark ii,and Procad showed nearly same results.

Wear resistance of Ceramics was less than enamel.

ConclusionConclusion; ; With the development of newer With the development of newer

advancements in CAD COM technology advancements in CAD COM technology restorations that can fit accurately ,and are restorations that can fit accurately ,and are esthetic can be fabricated with very short esthetic can be fabricated with very short time and can eliminate routine lab time and can eliminate routine lab procedures there by produe more procedures there by produe more predictable results. predictable results.

. .

ReferencesReferences

JPD vol/14/No:1, March 2005 pp 39-95

JPD July 2006,47-52

JPD1996 76; 187; 93

JPD vol /84 no:2 154-62Dental implant prosthetics MIschTylman

Rosential

Sirona dental implants-Document

Dental products survey report 2005

CICERO CAD CAM

CEREC implants Google search

Vision 2010Venue: SRM Dental college Dept of

prostho

Time: 8:30 - A patient walks into dept

with a need for missing upper front teeth

8:40 - case discussion &treatment planning; patient opts for bridge

9:00 - tooth preperation finished; optical impression is made; pt is advised to have a break eat kit-kat in canteen & report in half an hour.

9:30 - CAD/CAM restoration is ready

10:00- pt walks out happily

THANK YOU