RECENT RECENT ADVANCES IN ADVANCES IN

DENTAL DENTAL CERAMICSCERAMICS

CONTENTSCONTENTS

• IntroductionIntroduction• History History • Glass infiltrated aluminaGlass infiltrated alumina• InceramsIncerams• Procera all ceramProcera all ceram• Pressable ceramicsPressable ceramics• Machinable ceramicsMachinable ceramics• CAD CAMCAD CAM

INTRODUCTIONINTRODUCTION

Though conventional ceramics provide esthetically pleasing retorations they have many drawbacks which limit their use.With more and more studies coming in the field of ceramics and with the advent of digital technology newer and better products are flooding the market these days.The “chinese clay” of olden days have become the unavoidable product in esthetic dentistry...

• •

•* reinforced ceramic core systems

• metal-ceramics •resin-bonded ceramics

HISTORYHISTORY Since the stone age ceramics have been Since the stone age ceramics have been

important for humans.important for humans.

1789-de_chemant & Duchateau.1789-de_chemant & Duchateau. 1822-baking process.1822-baking process. 1825-commercial production by Stockton.1825-commercial production by Stockton. 1903-Dr.Charles Land-first ceramic crown1903-Dr.Charles Land-first ceramic crown 1962-Patents by weinstien and wenstein.1962-Patents by weinstien and wenstein. 1965-Mclean & Hughes1965-Mclean & Hughes

CLASSIFICATIONCLASSIFICATION

USE

COMPOSITION

PROCESSING METHOD

FIRING TEMP. MICRO STRUCTURE

TRANSLUCENCY

ABRASIVENESS

OPAQUE TRANSLUCENT TRANSPARENT

GLASS

CRYTALLINE

CRYSTAL -GLASS

LOW FUSING

MEDIUM

HIGH FUSING

SINTERING

PARTIAL SINT

GLASS INFIL.

CAD-CAM

COPY MILLING

PURE ALUMINA

P.ZIRCONIA

P.SILICA GLASS

LEUCITE.G.CER

LITHIA BASED

ANT.POST.CROWNSVENEERSP&C

WHY DO WE NEED WHY DO WE NEED ADVANCED PRODUCTS ???ADVANCED PRODUCTS ???

• One of the most serious drawbacks with the One of the most serious drawbacks with the early dental porcelains were their early dental porcelains were their lack of lack of strength and toughness, strength and toughness, which seriously which seriously limited their use. In order to overcome these limited their use. In order to overcome these problems, there are two possible solution. problems, there are two possible solution.

1.1.One solution is to provide the dental One solution is to provide the dental porcelain with support from a stronger porcelain with support from a stronger substructure. substructure.

2.2.The other option is to produce ceramics, The other option is to produce ceramics, which are stronger and tougher. which are stronger and tougher.

Metal free ceramic Metal free ceramic systemssystems

All ceramic systems can provide All ceramic systems can provide better esthetics.better esthetics.

Wide range of tranlucency opacities Wide range of tranlucency opacities are availableare available

Soft tissue healthSoft tissue health No over contouringNo over contouring

Glass infiltrated aluminaGlass infiltrated alumina

In-ceram aluminaIn-ceram alumina Supplied as one of the three core Supplied as one of the three core

ceramics.ceramics. 1)in-ceram spinell1)in-ceram spinell 2)in-ceram alumina2)in-ceram alumina 3)in-ceram zirconia3)in-ceram zirconia

In - ceramIn - ceram

A slurry of material is slip cast on A slurry of material is slip cast on porous refractory die and heated in porous refractory die and heated in a furnace to produce a partially a furnace to produce a partially sineterd coping.sineterd coping.

This coping is infiltrated with glass This coping is infiltrated with glass at temp1100*c -4hrsat temp1100*c -4hrs

In-ceram aluminaIn-ceram alumina

Indication-anterior and posterior Indication-anterior and posterior crowns and anterior 3-unit FPDs.crowns and anterior 3-unit FPDs.

Flexuarl strength-500mPaFlexuarl strength-500mPa The final ICA core consists of 70wt% The final ICA core consists of 70wt%

alumina and 30wtalumina and 30wt%sodiumlnathanum glass.%sodiumlnathanum glass.

Advantages Advantages

Moderately high flexural strength Moderately high flexural strength and fracture resistance.and fracture resistance.

A metal free structureA metal free structure An ability to be used succesfully with An ability to be used succesfully with

conventional luting cementsconventional luting cements

Drawbacks Drawbacks

Marginal seal is not as good as Marginal seal is not as good as procera-all ceram or IPS Empress.procera-all ceram or IPS Empress.

High degree of opacityHigh degree of opacity Inability to be etchedInability to be etched Technique sensitiveTechnique sensitive

In ceram spinnelIn ceram spinnel

Indications-anterior single unit Indications-anterior single unit creowna,inlays,onlays & veneers.creowna,inlays,onlays & veneers.

It is the most translucent among the It is the most translucent among the three .three .

It was introduced as an aletrnative It was introduced as an aletrnative to ICAto ICA

Improved translucency.....better Improved translucency.....better esthetics.esthetics.

  single anterior

s

anterior bridges

single posterio

rs

posterior bridges

 

Inlays onlays veneers

In-Ceram Spinell

X  

   X X X

 

             In-

Ceram Alumin

a

X X X  

     

               In-

Ceram Zirconi

a

 

 X X  

   

In ceram zirconiaIn ceram zirconia

Indication-posterior crownsIndication-posterior crowns

Not recommended in anteriors due to Not recommended in anteriors due to the high degree of opacitythe high degree of opacity

But has good modulous of elasticity But has good modulous of elasticity and fracture toghness.and fracture toghness.

Though it has better strength its use is Though it has better strength its use is limited to posteriors due to its greater limited to posteriors due to its greater opacity.opacity.

Castable and machinable Castable and machinable ceramicsceramics

When used in posteriors ceramic When used in posteriors ceramic crowns are succeptible to fracture.crowns are succeptible to fracture.

Critical flaw...??Critical flaw...??

First commercially available castable First commercially available castable ceramic-ceramic-dicor,developed by corning dicor,developed by corning glass works.glass works.

Dicor is a castable glass.Dicor is a castable glass.

Indicated forIndicated for onlays,facial onlays,facial veneersveneers,full,full crown restorations.crown restorations.

technique......technique......cerammingceramming

Procera all ceram Procera all ceram

Composed of densely sintered high Composed of densely sintered high purity Aluminium oxide core+all ceram purity Aluminium oxide core+all ceram veneering porcelain.veneering porcelain.

Contains 99% alumina.Contains 99% alumina.

It is one of the hardest among the It is one of the hardest among the ceramics.ceramics.

Indications-anterior & posterior Indications-anterior & posterior crowns,veneers,onlays...crowns,veneers,onlays...

Procera scanner is used.Procera scanner is used.

It is developed through CAD-CAM It is developed through CAD-CAM processing.processing.

CAD-CAM ceramicsCAD-CAM ceramics

Computer aided designing and Computer aided designing and computer aided milling.computer aided milling.

The internal surface of inlays or The internal surface of inlays or crowns is ground with diamond discs crowns is ground with diamond discs according to the scanned image of the according to the scanned image of the praparation praparation

ADVANTAGESADVANTAGES

No wear of the opposing toothNo wear of the opposing toothStrengthStrengthFracture resistanceFracture resistanceLow translucensyLow translucensy

Lava zirconiaLava zirconia

They are zirconia based products.They are zirconia based products.

First the milled prosthesis is removed First the milled prosthesis is removed from the milling unit.from the milling unit.

The zirconia frame work is placed in The zirconia frame work is placed in the cercon furnace and fire at the cercon furnace and fire at 1350*C for 6 hours. 1350*C for 6 hours.

The purest tetragonal zirconia has The purest tetragonal zirconia has got the greatest fracture toughness got the greatest fracture toughness and flexural strength.and flexural strength.

Contra indicated in patients with Contra indicated in patients with bruxism.bruxism.

Only minimal occlusal reduction of Only minimal occlusal reduction of 2mm needed.2mm needed.

FinesseFinesse all ceramic all ceramic

It is a new product patended to It is a new product patended to dentsply.dentsply.

Indications-crowns Indications-crowns ananterior&posteriorterior&posterior

VeneersVeneers

InlaysInlays

onlaysonlays

• Finesse All-Ceramic achieve an ideal Finesse All-Ceramic achieve an ideal bond without the need to create a bond without the need to create a wash layerwash layer

• Thus saving time and enhancing the Thus saving time and enhancing the strength of the restoration.strength of the restoration.

• It is a leucite reinforced ceramic It is a leucite reinforced ceramic glass material.glass material.

• Flexural strength- 125mPaFlexural strength- 125mPa

• "Pressing" - lost wax injection "Pressing" - lost wax injection moldingmolding

• At 930°C, for 20 minAt 930°C, for 20 min• Inherently fluorescent Inherently fluorescent • Ideal transparency range from Ideal transparency range from

(clear) to (opaceous)(clear) to (opaceous)

PRESSABLE CERAMICSPRESSABLE CERAMICS

Introduces by MAC CULLOCH IN Introduces by MAC CULLOCH IN 19681968

Here,the glass is formed into the Here,the glass is formed into the devised shape.devised shape.

Then it is subjected to partial Then it is subjected to partial devitrification.a presssure devitrification.a presssure moulding technique is followed.moulding technique is followed.

• IPS empress-IPS empress-is a glass ceramic is a glass ceramic avialable as ingots,avialable as ingots,

• Which can be heated and pressed Which can be heated and pressed until the ingots flows into a mold.until the ingots flows into a mold.

• It contains higher concentration of It contains higher concentration of leucite crystals that increase the leucite crystals that increase the resistance to crack propagation.resistance to crack propagation.

• It can be tained ,glazed or built up by It can be tained ,glazed or built up by layering technique.layering technique.

No metal componentNo metal component• Translucent ceramic coreTranslucent ceramic core• Moderately high flexural strengthModerately high flexural strength• Excellent fitExcellent fit• Excellent estheticsExcellent esthetics

ADVANTAGESADVANTAGES

Disadvantages Disadvantages

Potential to fracture(in posterior)Potential to fracture(in posterior)

Requires a resin cement to Requires a resin cement to micromechanically bond to the micromechanically bond to the tooth structure.tooth structure.

Y - TZP...??Y - TZP...??

Yttrium tetragonal Yttrium tetragonal zirconia polycrystalzirconia polycrystal

• One the latest advacements in the One the latest advacements in the field of all ceramic restorations.field of all ceramic restorations.

• Phase transformation from Phase transformation from monoclonal to tetragonal on firing.monoclonal to tetragonal on firing.

• Adding zerconia stablizes the core Adding zerconia stablizes the core during this phase transformation.during this phase transformation.

• Also the presence of water causes Also the presence of water causes crack propagation and stress crack propagation and stress corrosion reactions.corrosion reactions.

• But Y-TZP substructures are But Y-TZP substructures are independent of this phenomena.independent of this phenomena.

• In vitro studies show a flexural In vitro studies show a flexural strength of 900-1200mPa.strength of 900-1200mPa.

Hydroxy apatite based Hydroxy apatite based ceramicsceramics

• Cera pearl,Cera pearl,developed bydeveloped by Kyocera Kyocera co. in CA.co. in CA.

• Here the main ceystalline phase is Here the main ceystalline phase is oxy apatite which can be oxy apatite which can be tranformed to hydroxy apatite on tranformed to hydroxy apatite on hydration.hydration.

• Commonly used in implants...for Commonly used in implants...for better flexural strength and better flexural strength and bonding.bonding.

ShadeShade

• Dimensions of colorDimensions of color

Metamerism & Flouresence

Hue

Chroma

Value

Conclusion Conclusion

• Advances in the field of ceramics Advances in the field of ceramics gives hand full of newer products gives hand full of newer products for the dentist.for the dentist.

• Which will surely enhance the Which will surely enhance the esthetic and strength characters.esthetic and strength characters.

• A carefull selection of these A carefull selection of these products are essential for products are essential for successful outcome.successful outcome.

Bibliography Bibliography

• Text book of dental materials-Text book of dental materials-Anusavice.Anusavice.

• Dental technitian news letterDental technitian news letter-2009 -2009 marchmarch

• Text book of ceramics fabrication-Text book of ceramics fabrication-Naylor.Naylor.

• Recent advances in ceramics-Recent advances in ceramics-Dr.Jennifer,ohio,USADr.Jennifer,ohio,USA

T H A N K Y O U