All Ceramics - Dental

All Ceramics Dr. Nithin Mathew

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ALL CERAMICS(Material Aspect)

Dr. Nithin Mathew


CONTENTS

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Introduction

History

Classification

Composition

Advantages & disadvantages

Manufacture

Fabrication

Methods of strengthening ceramics

All Ceramic Systems

Selection of ceramics

Conclusion

References


INTRODUCTION

Ceramic - First material to be artificially made by humans.

Ceramic is derived from the Greek word keramos, which means potter's clay.

Earliest techniques consisted of shaping the item in clay/soil and then baking it to fuse the

particles together, which resulted in coarse and porous products.

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The term CERAMIC refers to any product made essentially from a non metallic inorganic

material processed by firing at a high temperature to achieve desirable properties.

DENTAL CERAMIC (Anusavice)

A specially formulated ceramic material that exhibits adequate strength, durability and

color that is used intraorally to restore anatomic form and function, and/or esthetics.

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CERAMICS

Compounds of one or more metals with a non metallic element (usually silicon,

boron, oxygen) that may be used as a single structural component or as one of the

several layers that are used in the fabrication of a ceramic based prosthesis.

(Glossary of Prosthodontic Terms)

PORCELAIN

A ceramic material formed of infusible elements joined by lower fusing materials.

(Glossary of Prosthodontic Terms)

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Terminologies

COPY-MILLING

A process of machining a structure using a device that traces the surface of master

metal, ceramic, or polymer pattern and transfers the traced spatial positions to a

cutting station where blank is cut or ground in a manner similar to key-cutting

procedure.

SINTERING

The process of heating closely packed particles to achieve interparticle bonding and

sufficient diffusion to decrease the surface area or increase the density of the

structure.7


VITRIFICATION :

The development of a liquid phase by reaction or melting, which on cooling provides

the glassy phase, resulting in a vitreous structure.

When the glass begins to crystallize , the process is called DE-VITRIFICATION.

GREEN STATE :

A term referred to as pressed condition before sintering.

SPINEL :

A crystalline mineral composed of mineral oxides such as magnesium oxide or

aluminium oxide.

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SLIP CASTING :

A process used to form green ceramic shapes by applying a slurry of ceramic

particles and water or special liquid to a porous substrate, thereby allowing capillary

action to remove water and densify the mass of deposited particles.

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All Ceramics Dr. Nithin Mathew 10

ADA SPECIFICATION

Dental ceramic : 69

Dental porcelain teeth : 45

Metal ceramic system : 38

ISO SPECIFICATION

Dental ceramic : 6872

Dental porcelain teeth : 22112

Metal ceramic system : 9693


HISTORY

1728 : Proposed the use of porcelain in dentistry Pierre Fauchard

1774 : Made first porcelain denture Alexis Duchateau

1789 : First porcelain tooth material patented - de Chemant & Duchateau

1808 : Terrometallic porcelain tooth Fonzi

1817 : Porcelain teeth introduced in the US Planteau

1825 : Commercial production of porcelain teeth (SS White Company) Samuel Stockton

1837 : Introduced improved version of porcelain- Ash

1887 : Introduced porcelain jacket crown using platinum foil matrix technique - CH. Land

1903 : First ceramic crowns introduced to dentistry Charles Land

1957 : Introduced Vacuum firing - Vines & Sommelman

1962 : Formulation of feldspathic porcelain Weinstein & Weinstein11


1963 : First commercial feldspathic porcelain developed Vita Zahnfabrik

1965 : Aluminous core ceramic Mclean and Hughes

1968 : Use of glass ceramics MacCulloh

1983 : Bonding composite resin to acid etched porcelain Simonsen & Calamia

1983-84 : First castable ceramic Dicor Grossman & Adair

1985 : First CAD/CAM was publicly milled and installed in the mouth Morman & Brandestini

1987 : CEREC 1 was introduced

1989 : First slip cast alumina ceramic- Inceram alumina- Sadoun

1991 : Pressable glass ceramics- Wohlwent


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1997 : Sirona CROWN 1.0 program for producing full-ceramic posterior crowns was introduced


2008 : Sirona released the MCXL milling unit which can produce a crown in 4 mins

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CLASSIFICATION

Firing temperature

Use / Indications

Fabrication techniques

Crystalline phases

Microstructure

Translucency

According to system

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FIRING TEMPERATURE

High fusing : > 1300C

Medium fusing : 1101 - 1300C

Low fusing : 850 - 1100C

Ultralow fusing : < 850C

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USE / INDICATIONS

Veneers

All ceramic crowns

Inlays and onlays

Ceramic dentures

Post & Cores

Orthodontic brackets

FPD


FABRICATION TECHNIQUE

Sintered (Metal Ceramics)

Cast (Dicor)

Heat pressed (IPS Empress)

Slip cast (Inceram)

Machined (Cerec Vitablocs)

Partial sintering and glass infiltration

CAD CAM & copy milling

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CRYSTALLINE PHASE

Alumina based (Optec HSP)

Feldspar based (Conventional Ceramics)

Leucite based (IPS Empress)

Spinel based (Inceram Spinel)


TRANSLUCENCY

Opaque

Translucent

Transparent

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MICROSTRUCTURE

Glass

Crystalline

Crystal containing glass


COMPOSITION

Pure alumina

Pure Zirconia

Silica glass

Spinelle

Leucite based glass ceramic

Lithia based glass ceramic

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APPLICATION

Core porcelain

Body porcelain

Enamel porcelain


According To Systems

Metal ceramic systems Cast metal systems and non cast systems

All ceramic systems Conventional powder slurry ceramic

i. Alumina reinforced porcelain

ii. Magnesia reinforced porcelain

iii. Leucite reinforced

iv. Zirconia-whisker fiber reinforced

v. Low fusing ceramics

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Castable Ceramicsi. Flouormicasii. Other Glass Ceramics

Machinable Ceramicsi. Analogus Systems

a. Copymillinga. Mechanicalb. Automated

b. Erosive Techniques a. Sono - erosionb. Spark - erosion

ii. Digital Systems (CAD/CAM)i. Directii. Indirect

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Pressable Ceramicsi. Shrink free ceramicsii. Leucite reinforced ceramics

Infiltrated Ceramicsi. Alumina basedii. Spinel basediii. Zirconia based


Primary constituent Minerals composed of potash (KO), soda(NaO) and silica (SiO) 75-85%

Feldspar

4-5% Increases the moldability of the plastic porcelain Serves as a binder Consists of AlO 2SiO 2HO (Hydrated Aluminium Silicate) Kaolin is opaque and can lower the translucency of porcelain

Kaolin

Present in concentrations of 13-14% Provide strength, firmness and improve translucency of porcelain Serves as a framework for other ingredients

Quartz

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Composition of Dental Ceramics


GLASS MODIFIERS

Potassium, sodium and calcium oxides

Serve as fluxes

Lower the viscosity of glass

Increase thermal expansion

OPACIFYING AGENTS

Zirconium oxide

Titanium oxide

Tin oxide


PIGMENTS

To obtain various shades to mimic natural tooth colour.

Made by fusing metallic oxide with fine glass and feldspar & regrinding to a powder.

.

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Metallic oxide Colour

Iron or nickel oxide Brown

Copper oxide Green

Titanium oxide Yellowish brown

Manganese oxide Lavender

Cobalt oxide Blue


ADVANTAGES of Dental Ceramics

Highly esthetic

Biocompatibility

Electrical Resistance

Thermal Insulation

Wear resistance

Can be formed to precise shapes

Ability to be bonded to tooth structure

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DISADVANTAGES

Brittleness

Fabrication : Technique sensitive

Wear of opposing natural teeth

Difficult to repair intraorally

High cost of fabrication

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MANUFACTURING OF CERAMICS

Pyro-chemical reactions during manufacture of porcelain:

Ceramic raw materials are mixed together in a refractory crucible and heated to a

temperature well above their fusion temp

Series of reactions occur.

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CaCO3

P2O5

BaCO3

SiO2

Al2O3

MgO MgF2 CaF2



After the water of crystallization is lost,

Flux reacts with the outer layers of silica, kaolin and feldspar

Feldspar fuses and intermingles with kaolin and quartz

Feldspar undergoes decomposition to form glass and leucite

The molten glass begins to dissolve the quartz and kaolin

Continuous heating results in total dissolution

Then the fused mass is quenched in water

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CaCO3

P2O5

BaCO3

SiO2

Al2O3

MgO MgF2 CaF2


Internal stresses within the glass are produced and breaks into fragments frit

The process of blending, melting and quenching the glass is called FRITTING

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CaCO3

P2O5

BaCO3

SiO2

Al2O3

MgO MgF2 CaF2

Crucible


Melting

CaCO3

P2O5

BaCO3

SiO2

Al2O3

MgO MgF2 CaF2

Tank with cool water

Quenching

FritSieving



Ceramics : 2 phases

Glassy Phase (Vitreous) Provides translucency Makes ceramic brittle

Crystalline Phase Added to improve the mechanical properties Newer ceramics (35-90%)

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DISPENSING

Conventional dental porcelain kit supplied as a kit containing :

Fine ceramic powder in different shades of enamel, dentin, core/opaque

Special liquid or distilled water

Stains and colour modifiers

Glazes and add-on porcelain

Shade guide

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FABRICATION OF CERAMIC RESTORATIONS

The fabrication of conventional porcelain restoration is by : Condensation Sintering Glazing Cooling

CONDENSATION :

Padding or packing of wet porcelain into position The movement of particles is generated by vibration, spatulation or whipping, brush

technique and spray opaquing.

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CONDENSATION :

Build-up of Cervical Porcelain

Build-up of Body Porcelain

Cut-back

Build-up of Enamel Porcelain

Condensation methods:

MANUAL CONDENSATION ULTRASONICCONDENSATION

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Advantages of ultrasonic condensation:

Reduces the fluid content of layered ceramics; resulting in denser and more vibrant porcelainmass.

Enhances translucency and the shade qualities of the fired ceramic.

Shrinkage can be reduced to below 5%

Time-saving as it reduces the number of compensatory firing cycles

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SINTERING / FIRING :

Process of heating closely packs particles to achieve interparticle bonding and sufficient

diffusion to decrease the surface area or increase density of the structure.

Process of partial fusion of compact glass

Steps:

Pre-heating the furnace

Condensed mass placed

Green porcelain is fired

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Pre-heating (Drying):

Placing the porcelain object on a tray in front of a preheated furnace at 650C for 5min for low

fusing porcelain and at 480C for 8min for high fusing porcelains till reaching the green or

leathery state.

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Significance:

Removal of excess water allowing the porcelain object to gain its

green strength.

Preventing sudden production of steam that could result in voids

or fractures.

Ceramic particles held together in the green state after all liquid has been dried off


SINTERING / FIRING :

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FIRING TECHNIQUES

According to temperature presetting:

Temperature controlled

method

Temperature time control

method

According to the media employed for firing:

AIR FIRING

Porosity due to air inclusion

VACUUM FIRING

Reduce porosity

DIFFUSABLE GASES

Helium, hydrogen or

steam are substituted for

the ordinary furnace


Stages of Maturity of Porcelain during Firing

Bisque bake

A series of stages of maturation in the firing of ceramic materials depending on the degree of

pyrochemical reaction and sintering shrinkage occurring before vitrification (glazing).

Low bisque

Medium bisque

High bisque

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Low bisque

Surface of porcelain is very porous and will easily absorb water.

Medium bisque

Surface is still porous but the flow of the glass grains is increased and entrapped air

will become sphere shaped.

High bisque

Surface is completely sealed and presents a smooth texture.

Overfired porcelain become milky or cloudy in appearance Devitrification.

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STAGES OF MATURITY

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Low bisque stage Medium bisque stage High bisque stage

Characteristics Grains of porcelain start to soften and coalesce at the contact points

Flow of glass grains increase and the residual entrapped furnace air becomes sphere shaped

Firing shrinkage is complete,and has adequate strength, for any corrections by grinding prior to glazing

Particle cohesion Incomplete Considerable CompletePorosity Highly porous and absorbs

waterReduced although still porous

Slight/absent depending upon the material used

Shrinkage Minimal Majority / definite CompleteStrength Weak & friable Moderate High Surface texture Porous Matte surface Egg shell appearance

Color & translucency

Opaque Less opaque Color and translucency developed


GLAZING :

Produces smooth, shiny and impervious outer layer, also effective in reducingcrack propagation.

2 ways : Add-on glazing Self glazing most preferred technique

COOLING :

Carried out slowly Rapid cooling results in cracking or fracture of glass and loss of strength. After firing, placed under a glass cover to protect it from air current and

contamination by dirt.41


Porcelain Surface Treatment

Natural or Autoglaze

Porcelain has the ability to glaze itself when held at its fusing temperature in air for 1-4

mins.

Porcelain loses its ability to form a natural glaze after multiple firings

Applied Overglaze

Applied overglaze is a low fusing clear porcelain painted on to the restoration and fired at

a fusing temperature much lower than that of the dentin and enamel porcelain.

An applied overglaze is indicated in large restoration that have numerous corrections.46


Instrumentation for Finishing and Polishing Ceramic Restorations

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Sequence Instruments

1 Medium to fine grit diamond instrument

2 30 fluted carbide burs

3 Rubber, abrasive impregnated porcelain polishing points

4 Diamond polishing paste


Methods of Strengthening Ceramics

Minimize the effect of stress raisers

Develop residual compressive stresses

Minimize the number of firing cycles

Ion exchange

Thermal tempering

Dispersion strengthening

Transformation toughening

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1. Minimize the effect of stress raisers

Stress raisers are discontinuities in ceramic and metal ceramic structure that causes stress

concentration.

Restoration should be designed in such a way that it avoids exposure of ceramic to high tensile

stresses.

Use of maximum thickness of ceramic on the occlusal surface.

Abrupt changes in the shape or thickness in ceramic contour should be avoided.

Sharp line angles in the preparation can cause stress concentration.

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2. Develop residual compressive stresses

The coefficient of thermal contraction of metal should be slightly higher than that of porcelain.

Metal contracts slightly more than the porcelain on cooling from firing temperature to room

temperature

Leave porcelain in residual compression and provides additional strength for the prostheses.

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3. Minimize the number of firing cycles

Leucite is a high expansion crystal phase which affects the thermal contraction coefficient of

porcelain.

Multiple firings increases concentration of crystalline leucite.

Increasing the no. of firing cycles can increase the LCTE of veneering porcelain. This leads to

stresses on cooling.

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4. Ion exchange/ Chemical tempering

Effective method of inducing residual compressive stresses.

Sodium containing glass article is placed in a bath of molten potassium nitrate

Exchange of ions take place

Since potassium ion is 35% larger than sodium ion, squeezing of the potassium ion createsvery large residual compressive stresses.

Potassium rich slurry, applied to ceramic surface and heated

to 450C for 30 mins.

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5. Thermal Tempering

Creates residual compressive stresses by rapidly cooling the surface of the object while it is in

the molten state.

Rapid cooling produces a skin of rigid glass surrounding a molten core.

The solidifying molten core as it shrinks, creates residual compressive stress within the outer

surface.

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6. Dispersion Strengthening

Process of strengthening ceramics by reinforcing them with a dispersed phase of a different

material.

Most dental ceramics are reinforced by dispersion of crystalline substances.

Ex. Alumina in aluminous porcelain, spinel in In Ceram.

When crystalline material such as alumina (AlO) is added to a glass, the glass is

strengthened and crack propagation does not take place easily.

Resulted in development of aluminous porcelain for porcelain jacket crowns.

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7. Transformation Toughening

This method also relies on dispersion of a crystalline material within the ceramic.

Strengthening occurs due to a change in the crystal structure under stress which prevents

crack propagation.

Dental ceramics based primarily on zirconia crystals when heated to a temperature between

1470C and 2010C undergo change in the crystal structure from tetragonal to a monoclinic

phase at approx. 1150C

The toughening mechanism results from the controlled transformation of metastable

tetragonal phase to the stable monoclinic phase.55


ALL CERAMIC SYSTEMS

Classified according to the method of fabrication:

Conventional (powder slurry) ceramics

Infiltrated / Slip Cast Ceramics

Castable Ceramics

Pressable Ceramics

Machinable Ceramics

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CONVENTIONAL CERAMICS(POWDER SLURRY)


Supplied as powders in different shades & translucencies.

Mixed with water to form slurry

Slurry build up in layers on a refractory die

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ALUMINOUS CORE PORCELAIN

Mc Lean and Hughes developed a PJC with an alumina reinforced

Significant improvement in fracture resistance

Consisted of a glass matrix containing between 40-50 wt% of Al2O3.

Large sintering shrinkage (15-20%)

Inadequate translucency

Principle indication: maxillary anterior crown restoration

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DisadvantagesAdvantages

Improved Fracture Resistance

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Low CTE : 8 x 10-6/0C.

Large sintering shrinkage (15-20%)

Improvement in strength is insufficient to

bear high stresses


MAGNESIA REINFORCED PORCELAIN

OBrien in 1984 High expansion ceramics Core material Crystalline magnesia (40-60%) Forsterite.

Magnesia crystals strengthen glass matrix by both dispersion strengthening and crystallizationwithin the matrix .

Flexural strength is 131 MPa Doubled upto 269 MPa by the addition of glaze.

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Advantages

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Increased co-efficient of thermal expansion

Improved strength (glass infiltration of magnesia core)

High expansion property


LEUCITE-REINFORCED PORCELAIN

They are feldspathic porcelains, dispersion strengthened by crystallization of leucite crystalsin the glass-matrix.

The leucite and glassy components are fused during the baking process at 10200C.

Leucite crystals in the glass - matrix (50%).

Strength : Nucleation and growth of leucite crystals.

Translucency : Closeness of the refractive index of leucite with that of the glass matrix.

Flexure strength : approximately 140 MPa.63



High strength (leucite reinforcement)

Good translucency

Moderate flexural strength

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Marginal inaccuracy due to sinteringshrinkage.

Fracture in posterior teeth.

High abrasive effect on opposing teeth.


INFILTRATED / SLIP CAST CERAMICS


GLASS INFILTRATED CORE CERAMICS Inceram Alumina Inceram Spinel Inceram Zirconia

2 components : Powder & Glass

Fabrication: Powder mixed with water to form suspension called SLIP SLIP is painted onto refractory die : absorbs water leaving solid alumina Baked at 11200C for 10 hours : opaque, porous core Glass powder applied to core and fired at 11000C for 3-4hrs Molten glass infiltrates the porous alumina or spinel by capillary action Veneering

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Die preparation Mixing aluminous powder with water to produce slip

The slip is painted onto the die with a brush

The water is removed by the capillary action of the

porous gypsum, which packs the particles into a

rigid porous network

Sintering : 10 Hrs 11200C

Porous network


Glass powder is used to fill the pores in the alumina core.

Glass Infiltration (4hrs 11000C)Glass becomes molten and flows into the

pores by capillary diffusion

Removal of excess glass Veneering with esthetic porcelain


The internal surface is sandblasted (with 50 A12O3)

Since the density of In-ceram core makes conventional methods of etching with HF acid

ineffective for bonding with a resin-cement.

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INCERAM ALUMINA

Developed by a French scientist and dentist Dr. Michael Sadoun (1980) and first introduced in

France in 1988.

Composition:

Two three-dimensional interpenetrating phases :

Alumina/ Al2O3 crystalline : 99.56 wt%

An Infiltration of glass lanthanum aluminosilicate

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Lanthanum

Decreases the viscosity of the glass to assist infiltration

Increases its refractive index to improve translucency.

Fabrication stages :

Slip casting Veneering of core

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PROPERTIES

STRENGTH :

Densely packed crystalline particles (70% alumina) limit crack propagation and prevent

fracture.

Flexure strength : 450 MPa range

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PROPERTIES

COLOR :

Final color : influenced by the color of the alumina core (opaque).

Colorants used : transitional metal ions incorporated into the glass structure itself

Spinel ceramic : the core is more transparent and its corresponding infiltration glass is slightlytinted.

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Minimal firing shrinkage, hence an

accurate fit.

High flexure strengths (3 times)

Aluminous core (opaque) : used to cover

darkened teeth or post/ core.

Wear of opposing teeth is lesser

Biocompatible : less plaque accumulation.

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Requires specialized equipment.

Poor optical properties or esthetics

(opaque alumina core)

Incapability of being etched

Slip casting is a complex technique

Considerable reduction of tooth surface


IN-CERAM SPINELL

Introduced due to the comparatively high opacity of the alumina core.

Incorporating magnesium aluminate (Mg A12O4) results in improved optical properties

characterized by

Increased translucency

About 25% reduction in flexural strength

Spinel or Magnesium aluminate (Mg A12O4) is a composition containing A12O3 and Mg2O.

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Spinel renders greater strength

characteristics.

Spinell has extended uses (Inlay / Onlay,

ceramic core material and Veneers.)

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Incapable to be etched by HF

25% reduction in flexural strength.


IN-CERAM ZIRCONIA

A mixture of zirconium oxide / aluminium oxide is used as a framework material,.

Physical properties were improved without altering the proven working procedure.

The final core of ICZ consists of

30 wt% zirconia

70 wt% alumina.

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High flexural strength

1.4 times the stability

2-3 times impact capacity compared to

ln-Ceram Alumina

Excellent Marginal Accuracy

Biocompatibility

78

Poor esthetics due to increased opacity

Inability to etch


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CASTABLE CERAMICS


Introduced by Mc Culloch in 1968

Di-Cor New types

Cera pearl Canasite glass ceramic Optimal pressable ceramic Olympus castable ceramics Castable phosphate glass ceramic

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Supplied as ceramic ingots

Fabricated using Lost Wax technique and Centrifugal casting technique

Steps: Wax pattern invested Dewaxing Molten glass cast into mould using centrifugal casting machine Glass core : ceramming (heat treatment process)

Microscopic plate-like crystals grow within the glass matrix Veneered using feldspathic ceramics : Dicor Plus

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DI-COR (Dentsply + Corning Glass Co)

First commercially available castable ceramic material.

Non porous, non homogenous, microstructure with uniform crystal size which is derived from

the controlled growth of crystals within an amorphous matrix of glass.

Dicor composed of:

Tetrasilicic fluormica crystals : 55 % Glass ceramic : 45 %

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Major Ingredients Minor Ingredients

SiO2 : 45-70%

K2O : upto 20%

MgO : 13-30%

MgF2 (nucleating agent)

A12O3 : upto 2% (durability & hardness)

ZrO2 : upto 7%

Fluorescing agents (esthetics)

BaO : 1 to 4% (radiopacity)

Supplied as :

Special Dicor casting crucibles, 4.1 gm Dicor glass ingot

Dicor shading porcelain kit.


PROPERTIES

Flexural strength : 81 6.8 Mpa

Strength : 440-505 KHN

Biocompatible

Less bacterial counts : smooth surface, low surface tension, fluoride content.

84


PROPERTIES

Esthetics :

Gross man and Adiar Hue and chroma of metal ceramics and Castable ceramics matched natural teeth.

Value of only Castable ceramics matched natural teeth.

Presence of mica crystals scatter light similar to enamel rods.

Chameleon effect i.e. the restoration acquires a part of the color from adjacent teeth andfillings as well as the underlying cement lute.

85


PROPERTIES

Cementation : Zinc phosphate, light activated urethane resin Etching with ammonium difluoride for 2 min (Bailey & Bennet 1988)

Survival rate : Kenneth et al 1999 - 14yr study

Crowns : 82% Cores : 100% Inlay and onlay : 90% Partial coverage : 92%

Expenstein et al 2000 : Posterior 70%, anterior 82.7%

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Chemical and physical uniformity.

Excellent marginal adaptation

Compatibility with lost-wax castingprocess.

Ease of adjustment

Low thermal conductivity

Radiographic density is similar to that ofenamel

87

Requires special equipments

Veneers failure rate as high as 8%

Must be stained with low fusing feldspathicporcelain


CASTABLE APATITE GLASS CERAMIC (CERAPEARL)

1985 -Sumiya Hobo & Iwata

Available as Cera Pearl

Crystalline microstructure similar to natural enamel

Mechanical properties superior to enamel

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Composition

CaO : 45% - reacts with P2O5

P2O5 : 15% - Aids in glass formation

SiO2 : 35% - Forms the glass matrix.

MgO : 5% - Decreases the viscosity (anti flux)

Other : Trace elements (Nucleating agents during ceramming)

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CHEMISTRY

90

CaPO41460C

1510CAmorphous

Mass750C

870CCrystalline Oxyapatite

Exposed to moisture

HydroxyApatite

Ceramming

Ceramming :

The ceramming oven is preheated at 750C for 15 minutes. After the cast glass ceramic isplaced in the oven the temperature is raised at the rate 500C / min until it reaches 870C and heldfor 1 hr.

External staining : Cerastain ( Bioceram )


PROPERTIES

Cerapearl is similar to natural enamel in Composition

Density : 2.97 gm/cm2 Refractive index : 1.66 Thermal conductivity : 0.002 Hardness : 343

Clinical success : (crowns) 2 year success rate 100%

91


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PRESSABLE CERAMICS


Supplied as ceramic ingots

Fabricated using Lost Wax technique and heat pressed into the mould

Steps: Wax pattern invested in phosphate bonded investment Placed in specialized mould with alumina plunger After burnout, ceramic ingot is placed under plunger and heated to 11500C Veneered using feldspathic ceramics

93


CLASSIFICATION

Shrink free ceramics Cerestore Al-ceram

Leucite reinforced glass ceramics IPS empress Optec/OPC

Lithia reinforced glass ceramic IPS empress 2 OPC 3G

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CERESTORE (Shrink Free Ceramics)

Consists of Al2O3 and MgO mixed with Barium glass frits.

On firing crystalline transformation produces Magnesium aluminate spinel, which occupies a

greater volume than the original mixed oxides compensates for the conventional firing

shrinkage.

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Unfired Cerestore core : Al2O3 MgO Glass frit Silicone resin Fillers

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Fired Cerestore core : - Al2O3 (Corrundum) MgAl2O4 (Spinel) Ba Mg2Al3 (Si9Al2O3) Barium osumilite


Chemical And Crystalline Transformation

Silicone Resin SiO SiO2 Alumina Aluminosilicate(160-8000C)

(900-13000C)

Al2O3 + MgO MgAl2O4 (decreased shrinkage )

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PROPERTIES

Flexural strength : 225 Mpa

Fit : exceptional fit because of direct moulding process.

Low thermal conductivity

Radiodensity similar to enamel

Biocompatible

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Advantages

Dimensional stability of the core material in the molded (unfired) and fired states

Better accuracy of fit and marginal integrity

Esthetics

Biocompatible (inert) and resistant to plaque formation (glazed surface)

Radio density similar to that of enamel

Low thermal conductivity; thus reduced thermal sensitivity

Low coefficient of thermal expansion and high modulus of elasticity results in protection ofcement seal

99


Disadvantages

Complex

Specialized laboratory equipment and cost

Inadequate flexural strength compared to the metal-ceramic restorations

Poor abrasion resistance, hence not recommended in patients with heavy bruxism orinadequate clearance

LIMITATIONS and high clinical failure rates of the Cerestore led to the withdrawal of this

product from the market.

Improved version : 70 to 90% higher flexural strength - marketed as Al Ceram.

100


IPS-EMPRESS

Hot pressed ceramics

2 types:

Leucite reinforced (K2O Al2O3 4 SiO2)

Lithium Disilicate reinforced (SiO2 LiO2 P2O5 ZrO2)

101


COMPOSITION

Pre cerammed, pre colored : INGOTS SiO2 : 63% Al2O3 : 17.7% K2O : 11.2% Na2O : 4.6% B2O3 : 0.6% CaO : 1.6% BaO : 1.6% TiO2 : 0.2%

Contains higher concentration of leucite crystals, which increases the resistance to crackpropagation

102

Leucite content

Conventional Porcelain Dicor

IPS Empress Pressable ceramic

30-35% 50-60% 80-85%


FABRICATION

Lost-wax technique:

Wax pattern is invested

Burnout (at 850C)

The ceramic ingot plunger and the entire assembly is

preheated to 11000C

After 20 minute holding time the plunger presses the ceramic

under vacuum (0.3-0.4 MPa) into the mould

Held under pneumatic pressure (45-mins) to allow complete

and accurate fill of the mould.103


PROPERTIES

Flexural strength : 160-180 Mpa

The increase in strength has been attributed to : Pressing step which increases the density of leucite crystals Subsequent heat treatments which initiate growth of additional leucite crystals

Esthetics : High esthetic value (translucent, fluorescent) Clinical survival :

95% survival rate of 2-4 years (Deniz G et al 2002)

Marginal adaptation : Better marginal adaptation compared to aluminous core material.

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Advantages

Lack of metal or an opaque ceramic core

Moderate flexural strength (160-180 MPa)

Excellent fit (low-shrinkage ceramic)

Improved esthetics (translucent, fluorescent)

Etch-able

Less susceptible to fatigue and stress failure

Less abrasive to opposing tooth

Biocompatible material

105


Disadvantages

Potential to fracture in posterior areas.

Special laboratory equipment such as pressing oven and die material (expensive)

Inability to cover the color of a darkened tooth preparation or post and core, since the crownsare relatively translucent.

Compressive strength and flexural strength lesser than metal-ceramic or glass-infiltrated (In-Ceram) crowns.

106


IPS EMPRESS 2 (IVOCLAR)

Second generation of pressable materials for all- ceramic bridges.

Lithium disilicate crystal >60vol%.

The apatite crystals are layered which improved optical properties (translucency, light

scattering) which contribute to the unique chameleon effect.

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IPS Empress IPS Empress 2

Flexural strength Upto 150 MPa > 400 Mpa


Other applications : Core build-up system with the pre-fabricated zircon oxide root canal posts

Advantages

High biocompatibility Excellent fracture resistance High radiopacity Outstanding translucency

108


IPS E.MAX PRESS

Introduced in 2005.

Considered as an enhanced lithium disilicate press-ceramic material when compared to

Empress II.

Better physical properties and improved esthetics

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Strength

110


MACHINABLE CERAMICS


Impression

Casts & Die

Wax Pattern

Investing

Casting

Lost Wax Technique

Camera Contact Digitizer

Laser

Machine Sinter

Computerised Design

CAD / CAM System

Traditional Technique Higher Technology

Data Acquisition

Restoration Design

Restoration Fabrication

Electrical Discharge Machine


Application of CAD/ CAM techniques was actively pursued by three groups of researches

Group supported by Henson International of France.

Combined group effort between the University of Zurich and Brains, BrandestiniInstruments of Switzerland.

University of Minnesota, supported by the U.S. National Institute of Dental Research.

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FRENCH SYSTEM

Optical impression Laser scanner Data processing By Shape recognition software It has a library (memory) describing theoretical teeth.

The system uses: 3-D probe system based on electro-optical method Surface modelling and screen display Automatic milling by a numerically controlled 4-axis machine

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SWISS SYSTEM

Optical impression - Optical topographic scanning using a 3-D oral camera Data processing - By an interactive CAD unit

The system uses: A desk top model computer Display monitor permitting visual verification of quality of data being acquired Electronically controlled 3-axis milling machine

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MINNESOTA SYSTEM

Optical impression - Photograph based system using a 35-mm camera with magnifying lens.

Data processing - Data obtained in the dental office is sent to another location for processingand machining.

3-D Reconstruction uses : Direct line transformation and an alternative technique proposed by Grimson

Milling with a 5-axis milling machine

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CLASSIFICATION - Machinable Ceramics

117

ANALOGOUS SYSTEM DIGITAL SYSTEMS

I. Direct

II. Indirect

i. 3-D scanning

ii. CAD modelling

iii. Fabrication

I. Copy milling

i. Fabrication of prototype for scanning

ii. Copying and reproduction by milling

II. Erosive techniques

i. Sono Erosion

ii. Spark Erosion


FINE SCALE FELDSPATHIC PORCELAIN

I. CEREC VITABLOC MARK I:

Feldspathic porcelain Larger particle size (10-50 micron)

II. CEREC VITABLOC MARK II:

Feldspathic porcelain reinforcedwith aluminium oxide (20-30%)

Fine grain size (4 micron)

GLASS PORCELAIN

I. DICORFlurosilica Mica Crystals Plates (2 microns)

II. MGC F

Tetrasilica mica(enhance fluorescence, machinability)

III. PRO CAD

Leucite - Reinforced Glass Ceramic

(high strength)118

2 Classes of Machinable Ceramics


DIGITAL SYSTEMS

CAD-CAM:

Uses digital information about the tooth preparation or a pattern of the restoration to provide

a computer-aided design (CAD) on the video monitor for inspection and modification.

The image is the reference for designing a restoration on the video monitor.

Once the 3-D image for the restoration design is accepted, the computer translates the image

into a set of instructions to guide a milling tool [CAM] in cutting the restoration from a block of

material.

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STAGES OF FABRICATION

All systems ideally involve 5 basic stages:

1. Computerized surface digitization

2. Computer - aided design

3. Computer - assisted manufacturing

4. Computer - aided esthetics

5. Computer - aided finishing

The last two stages are more complex and are still being developed for including incommercial systems.

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Scanning 3D Miniature Camera

Microprocessor unit stores the pattern

Video display serves as a format for manual construction

Final 3-D restoration is developed from above again bymicroprocessor

CAD-CAM Procedure (10-15mins)


Electronic information is transferred to miniature multiple axis milling device

Milling device generates a precision fitting restoration from a standard ceramic block


CEREC SYSTEM

Brains. A. G, Switzerland in 1980 Manufactured in West Germany, Siemens group

Consists of: 3-D video camera (scan head) Electronic image processor with memory unit Digital processor Miniature Milling machine

123



Translucency and color of porcelain veryclosely to natural dental tissues

Quality of ceramic is not changed duringprocessing

Can be placed in one visit

Prefabricated ceramic is wear resistant

124

Occlusal anatomy to be developed

Inaccuracies in fit

Poor esthetics systems


CEREC 2 SYSTEM

Morman & Brandestini in 1994 Constant further development

Major changes include: Enlargement of grinding unit from 3 to 6 axes Sophisticated software technology : occlusal surfaces

Minor technical innovations: Magnification factor increased from 8x to 12x Improved grinding precision by 24 times Improved accuracy of fit

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CEREC 3 SYSTEM

Operator can record multiple images in seconds

Creates a virtual cast for entire quadrant

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OTHER DIGITAL SYSTEMS

DURET SYSTEM Francois Duret : produced by Sopha (France)

CICERO SYSTEM

COMET SYSTEM

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ADVANTAGES : Machinable Ceramics

Single visit

Good patient acceptance

Eliminates procedures like impression model making and fabrication of temporary prosthesis

Void free porcelains without firing shrinkage

Better adaptation

Inlay,onlay can be fabricated chair side

Eliminates asepsis

Since its computer assisted crowns of correct dimensions can be obtained

Glazing is not required : can be polished

Less abrasion of tooth structure : homogenous material128


DISADVANTAGES : Machinable Ceramics

Limitations in fabrication of multiple units

Inability to characterize shades and translucency

Inability to image in wet environment

Technique sensitive

Expensive

Limited availability

129


ANALOGUS SYSTEMS : COPY MILLING

CELAY SYSTEM

Switzerland in 1992

High precision manually operated

Key duplication

Advantage : Recreation of all surfaces.

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COPYING SIDE Various size probes represent

size of diff milling burs is runover surface of pattern

MILLING SIDE At same time matched rotary

instru-mills same shape out ofrestorative block


ANALOGUS SYSTEMS : EROSIVE TECHNIQUES

SONO EROSION:

Based on ultrasonic methods.

The ceramic blank is surrounded by an abrasive suspension of hard particles, such as boron

carbide, which are accelerated by ultrasonics, and thus erode the restoration out of the

ceramic blank.

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ANALOGUS SYSTEMS : EROSIVE TECHNIQUES

SPARK EROSION:

'Electrical Discharge Machining' (EDM)

Metal removal process using a series of sparks to erode material from a workpiece in a liquid

medium under carefully controlled conditions.

Liquid medium : light oil called the dielectric fluid.

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CERCON & LAVA ZIRCONIA CORE CERAMICS

133

Fabrication

Tooth preparation

Impression made

Wax pattern made on

model

Anchored on to the Cercon

Brain

Presinteredzirconia blank

attached on other side of brain unit

Unit activatedPattern scanned

Milled prosthesis then removed from unit and placed in the

cercon furnace (13500C for 6 hrs)

TrimmingFinished

ceramic core framework

Veneering


BONDING OF PORCELAINS

RESINCERAMIC BONDING

Function of the silane primer between porcelain and the composite resin plays an important

role.

Etching of ceramic surface with 7.5 to 10% hydrofluoric acid for 2-10mins and then followed

by silanization increased the bond strength to porcelain (Peremuter and Montagonon, 1981)

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METAL-CERAMIC BONDING

1. Chemical bonding across the metal-porcelain interface:

Diffusion between surface oxide on the alloy and ceramic

2. Mechanical interlocking:

Due to surface irregularity of the alloy Air abrasion with aluminium oxide particles

3. Residual compressive stresses:

Core has slightly higher CTE than porcelain Porcelain draws towards the coping on cooling : residual compressive forces

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REPAIR OF CERAMIC RESTORATIONS

1. PORCELAIN REPAIR :

Fracture is totally in porcelain

Simplest repair

Preparation of porcelain surface by bonding :

Surface roughening by using diamond burs, air abrasion and acid etching with 9.5% HF acid

Application of silane coupling agent & allowed to dry for 1 min.

Application of bonding agent

Shade matched composite

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2. MIXED (PORCELAIN/METAL ) REPAIR :

Involves exposed metal

More complicated

If remaining porcelain:

Adequate : exposed metal and remaining porcelain is veneered with compositeopaquer & subsequently with layers of shade matched composite.

Inadequate : exposed metal surface is used as an adhesive substrate afterpreparation for bonding with composite opaquer layer followed by shade matched

composite.

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3. METALREPAIR:

Involves the exposed metal with or no remaining porcelain

Most difficult

2 methods :

Veneering exposed metal surface with direct bonding of shade matched composite

after preparation of exposed metal surface for bonding.

Fabrication of an over casting: small areas of remaining porcelain are removed if

present. Crown / pontic is reduced circumferentially to provide room for both

porcelain and metal, & provide margin for the laboratory technician and a thin metal

overcasting with fused porcelain veneer is fabricated.

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OTHER APPLICATIONS OF CERAMICS

ALL CERAMIC POST & CORES

DRAWBACKS of conventional Metal Post & Core

Decrease depth of translucency of restoration

Shine through in cervical root, altering appearance of thin gingival tissue

Corrosion products

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ADVANTAGES of All-ceramic Post & Core

All ceramic restoration transmits certain percentage of incident light to ceramic core & post .

Color of final restoration will be derived from an internal shade

Depth of translucency in cervical root area

Biocompatible

MATERIALS USED Inceram Dense sintered alumina ceramic Zirconium oxide ceramics

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CERAMIC-DENTAL IMPLANTS

Ceramic oxides : resistant to corrosion Tissue grow into surface porosity Ceramic Coating for Implant

Bioactive Ceramics : High density Alumina, TriCalcium Phosphate, High Alumina polymercomposite

Inert Ceramics : Alumina, Zirconium Oxide

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CERAMIC INSERTS

Megafillers for direct posterior composite restorations Reduce bulk of composite resin Decrease shrinkage Minimize wear

Composition

Glass inserts Lithium alumino-silicate glass (heat treated & silanated)

eg: Beta Quartz Glass ceramic inserts

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CEROMERS

Ceramics + Polymers = Ceromers

Ceramics: Abrasion resistance High stability Esthetics

Composites Ease of final adjustments Excellent polishability Bonding with luting cement Possibility of repair

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ZIRCONIA IMPLANTS

A radical new solution to immediate dental implant placement.

Patients extracted tooth is laser scanned and modified in CAD

software

Machined out of zirconium

Implanted in the still healing socket

Provides incredibly natural looking results.

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An increase of the crystalline content as seen in the pressable materials and the fully sintered

zirconia generally corresponds to an improvement of the mechanical properties.

An increase of crystalline content of a glassceramic is accompanied with an increase of the

strength and fracture toughness.

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Strength, Fracture Toughness and Microstructure of a Selection of All-Ceramic Materials. Part I. Pressable and Alumina Glass-Infiltrated Ceramics

Part II. Zirconia-based dental ceramicsGuazzatoa, Mohammad Albakrya, Simon P. Ringerb, Michael V. Swain

Dental Materials (2004) 20, 441448


Vita Inceram crowns exhibited significantly higher fracture strength than conventional all-

ceramic crowns.

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An Evaluation of Two Modern All-Ceramic Crowns and their comparison withMetal Ceramic Crowns in terms of the Translucency and Fracture Strength

Girish Nazirkar, Suresh Meshram

International Journal Of Dental Clinics 2011:3(1):5-7


The fracture strength of monolithic high translucent zirconia crown is considerably higherthan that of porcelain-veneered zirconia crown cores, porcelain-veneered high translucent

zirconia crown cores and monolithic lithium disilicate crowns.

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Fracture strength of monolithic all-ceramic crowns made of high translucent yttrium oxide-stabilized zirconium dioxide compared to porcelain-veneered crowns and

lithium disilicate crownsCamilla Johansson, Gratiela Kmet, Johnny Rivera, Christel Larsson & Per Vult Von Steyern

Acta Odontologica Scandinavica 2014; 72: 145-153


Lithium Disilicate glass-ceramic restorations had higher fracture resistances than leucite

reinforced glass-ceramic restorations.

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Dynamic fatigue and fracture resistance of non-retentive all-ceramic full-coverage molar restorations. Influence of ceramic material and preparation design

Jan-Ole Clausen, Milia Abou Tara, Matthias KernDental Materials 26 (2010) 533538


Observations regarding zirconia-based all ceramic restorations compared with PFM restorations:

Better esthetically than typical PFM restorations

Long-term color stability probably will be the same as that with PFM restorations

Margins of the restorations have a more acceptable appearance than those of PFM.

Strength and service record of PFM restorations and zirconia based restorations in three-unit

prostheses is similar.

Gingival sensitivity to metal will be reduced or eliminated with use of zirconia-based.150

Choosing an all-ceramic restorative materialPorcelain-fused-to-metal or zirconia-based?

Gordon J. Christensen

JADA, Vol. 138; May 2007


SELECTION OF CERAMIC MATERIALS

Four broad categories or types of ceramic systems:

Category 1: Powder/liquid feldspathic porcelains

Category 2: Pressed or machined glass-ceramics

Category 3: High-strength crystalline ceramics

Category 4: Metal ceramics

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Ceramics: Rationale for material selection, Cosmetic Dentistry:2,2013


Clinical Parameters To Evaluate :

Individual teeth evaluated for specific material selection Assessing four environmental conditions in which the restoration will function

1. Substrate

2. Flexure risk assessment

3. Excessive shear and tensile stress risk assessment

4. Bond/seal maintenance risk assessment

Ceramics: Rationale for material selection, Cosmetic Dentistry:2,2013


1. Substrate

Is it enamel? How much of the bonded surface will be enamel? How much enamel is on the tooth? How much of the bonded surface will be dentine? What type of dentine will the restoration be bonded to? Is it a restorative material (e.g.

composite, alloy)?

High bond strength : Enamel

Dentine surfaces/composite : Less predictable

More stress - between dentine and composite - more damage to the restoration andunderlying tooth structure



Each tooth and existing restorations are evaluated for signs of past overt tooth flexure.

Signs

Excessive enamel crazing

Tooth and restoration wear

Tooth and restoration fracture

Micro-leakage at restoration margins

Recession

Abfraction lesions



Low risk Low wear; minimal to no fractures or lesions Patients oral condition is reasonably healthy

Medium risk Signs of occlusal trauma Mild to moderate gingival recession along with inflammation Bonding mostly to enamel is still possible There are no excessive fractures



High risk Evidence of occlusal trauma from parafunction; More than 50 % of dentine exposure exists Significant loss of enamel due to wear of 50 % or more Porcelain must be built up by more than 2 mm.


3. Excessive shear and tensile stress risk assessment

All types of ceramics (especially porcelains) are weak in tensile and shear stresses.

Ceramic materials perform best under compressive stress

If a high-stress field is anticipated : Stronger and tougher ceramics are needed

The substructure should reinforce the veneering porcelain by utilising the reinforced-porcelain system technique



Glass-matrix materials : powder/liquid porcelains and pressed or machined glass-ceramics,

require maintenance of the bond and seal for clinical durability.

If the bond and seal cannot be maintained, then high-strength ceramics or metal ceramics are

the most suitable, since these materials can be placed using conventional cementation

techniques.



Clinical situations in which the risk of bond failure is higher are

Moisture control problems

Higher shear and tensile stresses on bonded interfaces

Variable bonding interfaces (different types of dentine)

Material and technique selection of bonding

The experience of the operator


Category 1: Powder/Liquid Feldspathic Porcelains

Aesthetic Factors 0.20.3 mm is required for each shade change

Substrate Condition 50 % or more remaining enamel on the tooth 50 % or more of the bonded substrate is enamel 70 % or more of the margin is in enamel

Flexure risk assessment Higher risk and more guarded prognosis when bonding to dentine Increased enamel, prognosis improved Depending on the dentine/enamel ratio, the risk : low to moderate

Tensile and shear stress risk assessment

Low to low/moderate risk. Large areas of unsupported porcelain, deep overbite or overlap of

teeth, bonding to more-flexible substrates : Increase the risk of exposure to shear and tensile stresses

Bond/seal maintenance risk assessment

Absolute low risk of bond/seal failure

Indications Indicated for anterior teeth


Category 2: Pressed or Machined Glass-ceramics

Aesthetic Factors Minimum working thickness of 0.8 mm 0.20.3 mm for each shade change is required

Substrate Condition Less than 50 % of the enamel on the tooth Less than 50 % of the bonded substrate is enamel 30 % or more of the margin is in dentine

Flexure risk assessment Risk is medium for Empress, VITABLOCS Mark II and Authentic-type glass-ceramics and layered IPS e.max


Flexure risk is medium to high (and full crown preparation is not desirable)

Monolithic IPS e.max has been 100 % successful for as long as 30 months in service.


Risk is medium for Empress, VITABLOCS Mark II and Authentic-type glass-ceramics, and layered IPS e.max.

Medium to medium/high for bonded monolithic IPS e.maxIndications Thicker veneers, anterior crowns, and posterior inlay and onlays

Only indicated in clinical situations in which long-term bond and seal can be maintained.


Category 3: High-strength Crystalline CeramicsAesthetic Factors Minimum working thickness of 1.2 mm is required.Substrate Condition Substrate is not critical, since a high-strength core supports veneering

material.Flexure risk assessment Risk is high or low

For high-risk situations, core design and structural support for porcelain become more critical


Risk is high or low High-risk situations : Preparations should allow for a 0.5 mm core

plus 1 mm of porcelain Anteriors: There should not be more than 2 mm of unsupported incisal

porcelain. Molars : Better to use zirconia cores rather than alumina cores High risk molar : Full-contour zirconia restorations recommended.


If the risk of obtaining or losing the bond or seal is high, then zirconia is the ideal all-ceramic to use.

Indications When significant tooth structure is missing Unfavourable risk for flexure and stress distribution is present It is impossible to obtain and maintain bond and seal


Category 4: Metal ceramicsAesthetic Factors 1.51.7 mm is required for maximum aestheticsSubstrate Condition Substrate is not as critical, since the metal core supports the

veneering material.Flexure risk assessment Risk is high or low

For high-risk situations, core design and structural support for porcelain become more critical


Risk is high or low For high-risk situations, core design and structural support for

porcelain become more criticalBond/seal maintenance risk assessment

If the risk of obtaining or losing the bond or seal is high, then metal ceramics are an ideal choice for a full-crown restoration.

Indications Indicated in all full-crown situations, esp when all risk factors are high.


CONCLUSION

Dental ceramic technology is one of the fastest growing areas of dental material research and

development. The past decades have seen the development of several new groups of ceramics.

Each system has its own merits, but may also have shortcomings.

Combinations of materials and techniques are beginning to emerge which aim to exploit the

best features of each.

Glass-ceramic and glass-infiltrated alumina blocks for CAD-CAM restoration production are

examples of these.

The diversity and sophistication of the CAD-CAM systems may prove to be influential in the

future.164


REFERENCES

Philips science of dental materials - Anusavice

Craigs restorative materials

Dental materials & their selection - William O Brien

Clinical operative dentistry - principles and practice - Ramya Raghu

Textbookof Dental materials Mahalekshmi

Theory and practice of fixed prosthodontics - Tylmann

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Slide Number 1All ceramics(Material Aspect)Contents introductionSlide Number 5Slide Number 6TerminologiesSlide Number 8Slide Number 9Slide Number 10historySlide Number 12Slide Number 13classificationFIRING temperatureFabrication techniqueTranslucencyCOMpositionAccording To SystemsSlide Number 20Composition of Dental CeramicsSlide Number 22PIGMENTSAdvantages of Dental CeramicsdisadvantagesManufacturing of ceramicsManufacturing of ceramicsSlide Number 28Manufacturing of ceramicsSlide Number 30dispensingFabrication of CERAMIC RESTORATIONSSlide Number 33Slide Number 34Slide Number 35Slide Number 36Slide Number 37Stages of Maturity of Porcelain during FiringSlide Number 39Stages of maturitySlide Number 41Porcelain Surface TreatmentInstrumentation for Finishing and Polishing Ceramic RestorationsMethods of Strengthening Ceramics1. Minimize the effect of stress raisers2. Develop residual compressive stresses3. Minimize the number of firing cycles4. Ion exchange/ Chemical tempering5. Thermal Tempering6. Dispersion Strengthening7. Transformation TougheningAll ceramic systemsConventional ceramics(powder slurry)Slide Number 58Aluminous core porcelainSlide Number 60 Magnesia Reinforced PorcelainAdvantagesLeucite-reinforced porcelainSlide Number 64INFILTRATED / slip cast CERAMICSSlide Number 66Slide Number 67Slide Number 68Slide Number 69 INCERAM ALUMINASlide Number 71PropertiesPropertiesSlide Number 74 IN-CERAM SPINELLSlide Number 76 IN-CERAM ZIRCONIASlide Number 78castable CERAMICSSlide Number 80Slide Number 81DI-COR (Dentsply + Corning Glass Co)Slide Number 83propertiespropertiespropertiesSlide Number 87CASTABLE APATITE GLASS CERAMIC (CERAPEARL)Slide Number 89ChemistrypropertiesPRESSABLE CERAMICSSlide Number 93Classification CERESTORE (Shrink Free Ceramics)Slide Number 96Chemical And Crystalline TransformationPropertiesAdvantagesDisadvantagesIPS-EMPRESSCOMPOSITIONfabricationpropertiesAdvantagesDisadvantagesIPS EMPRESS 2 (Ivoclar)Slide Number 108IPS E.max pressStrengthmACHINABLE CERAMICSSlide Number 112Slide Number 113French systemSwiss systemMinnesota systemCLASSIFICATION - Machinable Ceramics2 Classes of Machinable CeramicsDIGITAL SYSTEMSStages of fabricationSlide Number 121Slide Number 122Cerec systemSlide Number 124CEREC 2 SYSTEMCerec 3 systemOTHER DIGITAL SYSTEMSAdvantages : Machinable CeramicsdisAdvantages : Machinable CeramicsANALOGUS SYSTEMS : COPY MILLINGANALOGUS SYSTEMS : Erosive techniquesANALOGUS SYSTEMS : Erosive techniquesCercon & lava zirconia core ceramicsBonding of porcelainsSlide Number 135Repair of ceramic restorationsSlide Number 137Slide Number 138Other applications of ceramicsSlide Number 140Slide Number 141Slide Number 142Slide Number 143Slide Number 144Slide Number 145Slide Number 146Slide Number 147Slide Number 148Slide Number 149Slide Number 150Selection of Ceramic materialsSlide Number 152Slide Number 153Slide Number 154Slide Number 155Slide Number 156Slide Number 157Slide Number 158Slide Number 159Slide Number 160Slide Number 161Slide Number 162Slide Number 163conclusionSlide Number 165referencesSlide Number 167

All Ceramics - Dental

Education

Transcript of All Ceramics - Dental