This document provides an overview of dental ceramics and CAD-CAM systems. It discusses the historical background, classification, composition, properties, and fabrication methods of ceramic restorations. Key points include that ceramics are classified based on their content, use, processing method, and firing temperature. Their composition includes feldspar, kaolin/clay, quartz, glass formers, modifiers, and coloring agents. Fabrication involves condensation, firing, and glazing techniques. All-ceramic restorations such as porcelain jacket crowns, alumina-reinforced ceramics, castables, pressables, infiltrated ceramics, and CAD-CAM systems are summarized.

1. GOOD MORNING

2. DENTAL CERAMICSDENTAL CERAMICS & CAD-CAM

3. FLOW CHART
-INTRODUCTION
-HISTORICAL BACKGROUND
-CLASSIFICATION
-COMPOSITION OF CERAMICS
-GENERAL PROPERTIES OF CERAMICS
-FABRICATION OF CERAMIC RESTORATIONS
- METAL CERAMIC RESTORATIONS

4. ALL CERAMIC RESTORATIONS
_ PORCELAIN JACKET CROWNS
- HI – CERAM
_LEUCITE INFILTRATED CERAMICS
- DUCERAM LFC
- OPTEC HSP
_ CASTABLE CERAMICS
- DICOR
-CERA PEARL
_ PRESSABLE CERAMICS :
- OPTEC OPC
- IPS EMPRESS

5. -INFILTRATED CERAMIC
RESTORATIONS
IN –CERAM
- MACHINED CERAMIC RESTORATIONS
• CAD- CAM SYSTEMS
-CERAC –I
-CERAC – II
-CERAC –III
- CAVITY PREPARATION FOR CAD CAM
- FABRICATION OF CAD CAM RESTORATIONS
- PORCELAIN INLAYS :
- ADVANTAGE / DISADVANTAGE
- INDICATION /
CONTRAINDICATION

6. • CAVITY PREPARATION OF CERAMIC INLAY:
-CLASS I
-CLASS II
-CLASS III
-CLASS IV
-CLASS V
- FABRICATION OF CERAMIC INLAYS
• PORCELAIN LAMINTAES AND VENEERS
• INDICATION / CONTRAINDICATION
• ADVANTAGE / DISADVANTAGE
• PREPARATION TECHNNIQUE
• FABRICATION OF VEEENR

7. CLASSIFICATIONCLASSIFICATION

8. Classification of ceramics :
1. By content :
- Regular feldspathic porcelain
-Aluminous porcelain
- Leucite reinforced porcelain
- Glass infiltrated alumina
-Glass infiltrated spinel

9. 2.By use :
-Artificial teeth
-core ceramic
-veneer ceramic
3. By processing method :
-sintering
-casting
- machining

10. 4. By their firing temperature :4. By their firing temperature :
-high fusing : 1300 c
- medium fusing : 1100-13000 c
-low fusing : 850 – 1100 c
-ultra low fusing : less than 850C
5. By method of firing ;5. By method of firing ;
- Air fired
-vaccum fired
- diffusable gas

11. 6.6. By their area of application :By their area of application :
-core porcelain
-body dentin porcelain
- gingival dentin porcelain
-incisal enamel

12. Composition of ceramics :
1. Feldspar :
-when mixed with metal oxides and fired, it forms a
glass phase that is able to soften and flow slightly
-This softening of glass allows porcelain particles to
coalesce together. This is called sinteringsintering
-. Seen in concentration of 75-85 %.
1. Kaolin / clay :
-it acts as the binder.
-When mixed with water , it forms a sticky mass which
allows unfired porcelain to be easily worked and
molded.

13. -On heating it reacts with feldspar and gives
rigidity.
-Its white in color and reduces
translucency .so its added only in
concentration of 4-5 %.
3. Quartz :
-It imparts more strength, firmness and
translucency.
-It gives stability of mass during heating by
providing a frame work.13-14%

14. • GLAZES:
It decreases pores on the surface of fired porcelain.
• This increases strength by decreasing the crack
propagation.
if glaze is removed by grinding, the transverse strength
is half of glazed porcelain.
1. self glazing :
-External glaze layer is not applied here.
-the completed restorations is subjected to glazing here.
2.Add on glazes:
-external glaze layer is applied here.
-They are uncolored glasses whose fusing temperature is
lowered by the addition of glass modifiers.
-Disadvantages : low chemical durability, difficulty to
apply evenly, difficult to get exact surface characteristics.

15. • 6.Colouring agents :
-These coloring pigments are produced by
fusing metallic oxides together with fine glass
and feldspar -Ex : iron / nickel oxides- brown ,
copper oxides-green, titanium oxide –yellowish
brown, cobalt oxide – blue.
7.Opacifying agents:
-Opacifying agents consists of a metal oxide
ground to a very fine particle size .
ex :cerium oxide, titanium oxide, zirconium oxide
–most popular.

16. 8.Stains:
-These powder is mixed with water and the wet mix is
applied with brush to the surface of porcelain before glazing.
-Internal staining is preferred as it gives life like results and
prevents direct damage to stains by surrounding
environment.
9.Glass former :
Glass formers are silica.
1.crystalline quartz
2.crystalline cristobalite
3.crystalline tridymite
4.non crystalline fused silica

17. 10.Glass modifiers :
- Potassium oxide , Sodium oxide , Calcium
oxide are used as glass modifiers
- they act as fluxes by lowering the softening
temperature of a glass
11. Intermediate oxides :
-Glass modifiers reduces the viscousity of
porcelain .
-It needs a high viscosity as well as low firing
temperature. This is done by the addition of AL 2
O3 and B2O3 .

18. GENERAL PROPERTIES OF CERAMICS
1.BIOLOGICAL PROPERTIES :
-They have excellent biocompatibility .
2. CHEMICAL PROPERTIES :
- It resist attack by chemicals.
-They have to be roughened by etching with hydrofluoric
acid or sand blasting to improve the retention of a cement to
the internal surface of the restoration
3.MECHANICAL PROPERTIES :
- Low tensile strength
-Exhibits little plastic deformation
-Have good compressive strength

19. 1.Compressive strength : 50000psi
2.tensile strength : 5000psi
3.shear strength:16000psi
4.elastic modulus : 10 × 106
psi
5.knoop hardness : 460
6. C T E :12 × 10 -6
psi
7. R.I : 1.52 – 1.54
4. THERMAL PROPERTIES :
-They have insulating capacity.
5. OPTICAL PROPERTIES :
-They have good optical properties
-They are translucent because of absence of free
electrons.

20. FABRICATION OF CERAMIC RESTORATIONFABRICATION OF CERAMIC RESTORATION
Condensation of porcelainCondensation of porcelain :
• POWDER + LIQUID BINDERPOWDER + LIQUID BINDER→ CONDENSATION→ CONDENSATION
• The process of packing the powder particles together and
removing the liquid binder is known as condensation.
• The main objective of building porcelain is to achieve maximum
packing density of the powder so as to reduce porosity and
shrinkage during firing.
Types of binder :Types of binder :
1.distilled water : most popular binder
• 2.propylene glycol: used in alumina core build up
• 3.alcohol or formaldehyde based liquids:for core build up

21. Building up of porcelain :Building up of porcelain :
1.The powder is mixed on a glass slab
2.Mix should not be over stirred to avoid air bubbles
3.High room temperature and dry atmosphere avoided as
powder can dry out rapidly due to which air spaces are
created in powder bed.
Methods of condensation :Methods of condensation :
1.vibration ; mild vibrations are used to pack wet powder
.vibra brush is used
2.spatulation : small spatula is used to apply and smoothen
the wet porcelain.this brings excess water to surface.
3.Dry brush technique : dry powder is placed with a
brush.water is drawn towards the dry powder and wet
particles are pulled together
4.ultrasonic: mild vibrations given electrically

22. • FACTORS DETERMINING EFFICIENCY OFFACTORS DETERMINING EFFICIENCY OF
CONDENSATION:CONDENSATION:
1. SIZE OF THE POWDER PARTICLES:
If only one sized particles are used – 45% voids
two sized particles _ 25% voids
three sized particles_ 22% voids
system that use 3 sized particles is called Gap grading
system
2.SHAPE OF THE POWDER PARTICLES
Round particles give better packing than angular
particles.

23. Firing of dental porcelain:
-During firing, the glass particles soften at their
contact areas and fuse together. this is referred to
as sintering.
-Temperature is raised gradually to the desired
one, to allow the air and gas bubbles to escape via
the grain boundaries. The powder becomes dense
and shrinks.

24. CHANGES DURING FIRINGCHANGES DURING FIRING
1-Loss of water which was added to the powder. free and
combined water is lost till a temperature of 480 degree
2-With further rise in temperature, particles starts fusing
together by a process called sintering.
3-Firing shrinkage – decrease in volume
32% for low fusing porcelain
28% for high fusing porcelain
4-Glazing occurs
at temperatures of 965 – 10650
c

25. Stages of firing :Stages of firing :
1.Low bisque :
-The surface of porcelain is porous.
- Porcelain has started to soften .
-Shrinkage will be minimal and fired body is extremely
weak and friable.
-Lacks translucency and glaze.
2.Medium bisque :
-The surface will be slightly porous
- The flow of glass grains will have increased.
-Definite shrinkage would have happened.
-Lacks translucency and glaze.
3.High bisque :
-Porcelain has smooth surface with a shine
-Shrinkage is complete.

26. • FIRING TECHNIQUESFIRING TECHNIQUES
- Temperature method
- Temperature time method
• MEDIAS FOR FIRINGMEDIAS FOR FIRING
• AIR
• VACCUM
• DIFFUSABLE GAS

27. AIR FIRINGAIR FIRING
- All porcelain mixes have some amount of porosity in
them. So once in air furnace, the furnace atmosphere
occupies the voids.
- More chance of porosity
VACCUM FIRINGVACCUM FIRING
- Reduces porosity
- Vaccum removes air from the interstitial spaces
before surface sealing occurs.
- Vaccum is then removed when porcelain is in hot
zone of furnace, and then when the air gets in, it
exerts a compressive effect on the surface, which
compresses the internal voids to 1/ 10 th of its original
size.

28. DIFFUSIBLE GAS FIRINGDIFFUSIBLE GAS FIRING
• Air is driven out of porcelain powder and diffusible
gasses like helium , hydrogen are used
• With these gases interstitial spaces donot enlarge under
increasing temperature , but decrease in size or
disappear.
• This is beacause the gases diffuse outwards through the
porcelain or actually dissolve in the porcelain.

29. Glazing :Glazing :
-glazing seals the open pores on the surface
-gives polish and smoothness to the surface
overglazeoverglaze ::external glaze layer has to be applied. These
are ceramic powders containing more amount of glass
modifiers thus lowering fusion temperature.
self glazeself glaze : All the constituents on the surface are melted
to form a molten mass of about 25 µm thickness.
Procedure :Procedure :
Introduce into muffle entrance for 1 minute. Place on firing
platform at 800c for 2 minutes. Hold for 940c for 2 minutes
and air fire.

30. • PORCELAIN POWDER FOR METAL CERAMICPORCELAIN POWDER FOR METAL CERAMIC
RESTORATIONS:RESTORATIONS:
- Greater quantity of feldspar is required to increase
the thermal expansion to a level compatible with the
metal coping.
- Increased amounts of metallic oxide opacifiers to
conceal the underlying metal
BONDING MECHANISMS BETWEEN CERAMICBONDING MECHANISMS BETWEEN CERAMIC
AND METAL :AND METAL :
1. Mechanical entrapment
2. Compressive forces
3. Vander vals forces
4. Chemical bonding – chromic oxide with base metals,
tin oxide and iridium oxide with noble metals

31. Advantages/ Disadvantages
Advantages:
– Metal reinforcement
– Better fracture resistance
– Better marginal fit due metal frame
Disadvantages
- Less esthetic
- Margins may appear dark due to metal

32. Anterior teethAnterior teeth
• Depth orientation grooves- flat end taper
• Incisal reduction – 2mm, flat end taper
• Facial reduction, incisal half- flat end taper
• Facial reduction, gingival half-flat end taper
1.2-1.4mm to compensate for porcelain
• Wing to be given if only porcelain facing is there with
metal backing. It is given lingual to contact area.

33. • Contra indications for wing:Contra indications for wing:
– If tooth structure is less due to caries proximally, then
wing is not to be used
– If there is over all full coverage of porcelain then wing
is not to be prepared.
– Functions of wing :Functions of wing :
• Preserve tooth structure
• Add torque resistance to preparation
• Reinforce the restoration
• Helps the lab person to know the exact point
where ceramic and metal meets

34. • Lingual reduction : small wheel diamond
• Lingual axial reduction : torpedo diamond
• Chamfer and shoulder finishing;
• Torpedo carbide finishing bur for metal
• No.171 bur for shoulder area
• RADIAL SHOULDER GIVENRADIAL SHOULDER GIVEN
• since it decreases the stress concentration
• roundened internal angles
• so less chance of fracture.

36. POSTERIOR TEETH
• Occlusal reduction-1.5-2mm for porcelain
• Functional cusp bevel-round end taper( lingual
of upper , buccal of lower), 1.5 mm if only
metal,2mm if porcelain
• Facial reduction ,occlusal half-flat end taper
• Facial reduction , gingival half- flat end taper,1.2
for base metal,1.4mm for noble metal.

38. METAL CERAMIC
RESTORATION

39. BOND FAILURE IN METAL CERAMICSBOND FAILURE IN METAL CERAMICS
BY O BRIENBY O BRIEN
• Between metal and porcelain
• Between metal oxide and porcelain
• Between metal and metal oxide
• Between metal oxide and metal oxide

40. ALL CERAMICSALL CERAMICS

41. CLASSIFICATION:
1.CONVENTIONAL POWDER & SLURRY CERAMICS
1. HI-CERAM ( ALUMINA REINFORCED)
2.OPTEC HSP(LEUCITE REINFORCED)
3.DUCERAM LFC
2. CASTABLE ALL CERAMIC RESTORATIONS
1. DICOR
2.CERAPEARL
3.PRESSABLE ALL CERAMIC RESTORATIONS
1.IPS EMPRESS
2.OPTEC PRESSABLE CERAMIC
4.INFILTRATED ALL CERAMIC RESTORATIONS
1.IN- CERAM
5. MACHINABLE ALL CERAMIC RESTORATIONS
1.CAD- CAM, COPY MILLING
2.EROSION TECHNIQUE

42. CONVENTIONAL POWDERCONVENTIONAL POWDER
AND SLURRY TECHNIQUEAND SLURRY TECHNIQUE

43. 1. PORCELAIN JACKET CROWNS:1. PORCELAIN JACKET CROWNS:
- they were very brittle and fractured easily.
-They were called as half moon fractures.
-they also showed poor marginal adaptation.
Processing :
- PJC are made using platinum foil technique
-a platinum foil is first adapted to the dye. The foil
acts as a matrix and supports the porcelain during
firing.

45. ALUMINOUS PORCELAIN JACKETALUMINOUS PORCELAIN JACKET
CROWN ( HI – CERAM )CROWN ( HI – CERAM )
• -so McLean and Hughes in1965, introduced porcelain
jacket crown with aluminous core to improve the strength
of traditional PJC.
• -Increased content of alumina ( 40-50%) in the core
strengthened the porcelain by interruption of crack
propagation.

46. --Factors affecting strength & opacity ofFactors affecting strength & opacity of
aluminous porcelain:aluminous porcelain:
1.1. Finer the grain size, greater the strength.
2.2.coarse grains are less opaque.
-so there is a compromise between strength and
esthetics.
-so average grain size to be 25mm which allows
light transmission of atleast 15%

47. 3.3.size of glass powder is less than 40 mm as this
sized powder softens and flows more easily
around alumina grains producing high sintered
densities.
4.4.Rounded grains are preferred over angular
ones, since angular ones interfere with the flow of
glass phase producing flaws around the grains and
reducing the strength.

48. 5.5.Alumina concentration should be around 40-50%
by weight . Concentration higher than this would
prevent complete flow and wetting by glass matrix.
PROPERTIES :PROPERTIES :
Compressive strength: 3,16000 psi
Transverse strength : 20000 psi
Shear strength : 21 000 psi
Modulus of rupture : 15000 psi

49. UsesUses ::
-- Due to reduced translucency , aluminous
porcelain is limited to forming refractory framework
capable of supporting weaker more translucent
dentin and enamel porcelains
- Only these two types of all ceramic restorations
are called porcelain jacket crowns.
-The rest of them were called ceramic jacket
crowns or CJSCJS or glass ceramic crowns.

50. UsesUses ::
-- Due to reduced translucency , aluminous
porcelain is limited to forming refractory framework
capable of supporting weaker more translucent
dentin and enamel porcelains
- Only these two types of all ceramic restorations
are called porcelain jacket crowns.
-The rest of them were called ceramic jacket
crowns or CJSCJS or glass ceramic crowns.

51. CASTABLE CERAMICSCASTABLE CERAMICS
OROR
GLASS CERAMICSGLASS CERAMICS

57. 1.A metal stable glass is first formed
after casting.
2. during subsequent heat treatment controlled
crystallization occurs with nucleation and
growth of internal crystals.
3. this conversion process of a glass to a partially
crystalline glass is called ceramming.ceramming.
Thus a glass ceramic is a multiphase solid
containing residual glass phase with a finely
dispersed crystalline phase
- It decreasing the crack propagation .

58. DICORDICOR
• It is composed of Sio2, K2o,Mgo, Mgf2
• Alo2, Zro2.added for durability
• Flourescing agent for esthetics
• Flouride acts as a nucleating agent and improve
fluidity of molten glass.
• After ceramming material is 55% crystalline

59. Fabrication :
-wax pattern made
-invested in phosphate bonded refractory material.
-molten glass (1358ºc)is then cast to the heated mold after
dewaxing.
-cast restoration is then freed from investment , covered by
protective embedment materialembedment material and made to ceramming.
- It takes 114 minutes to reach casting temperature of
1075ºc and maintain this for 1 hour. embedment tray is
then removed.
- cerammed glass is then build up with enamel and dentin

60. Properties :
compressive strength : 120000 psi
modulus of elasticity : 10.2 ×106
ps
esthetics :
- Esthetic due to their translucency which matches
that of natural tooth enamel
- Its made entirely of 1 material , and so no opaqueIts made entirely of 1 material , and so no opaque
substructuresubstructure
-- It gives a chameleon effect in which theIt gives a chameleon effect in which the
restoration acquires part of color from adjacentrestoration acquires part of color from adjacent
teethteeth
-Precision fit is seen with dicor

61. -durability: it can withstand 20 years of tooth brush
abrasion without any changes
-Tissue acceptance : it is high to periodontal
tissues because ,
1. there is no need for opaque porcelain to cover
metal substructure
2.absence of opaque layer helps clinician to2.absence of opaque layer helps clinician to
obtain natural translucency in gingival areaobtain natural translucency in gingival area
little discomfort occurs on contact with hot orlittle discomfort occurs on contact with hot or
cold foods because of its extreme low thermalcold foods because of its extreme low thermal
conductivityconductivity

62. Advantages :Advantages :
-excellent marginal fit
-high strength
-surface hardness & occlusal wear similar to
enamel
-can reproduce wax pattern precisely with lost wax
technique
-excellent esthetics
inherent resistance to plaque accumulation
disadvantages :disadvantages :
-chance of losing the low fusing feldspathic
shading porcelain, which have been applied for
good colour matching

63. MACHINABLE CERAMICSMACHINABLE CERAMICS

64. From 1988, machined ceramics came into
being. there are 2 major systems for the
fabrication of this technique
1. Analogous systems:
-Copy milling / grinding technique
-Erosive techniques
2.digital systems:
-cad-cam technology

65. COPY MILLING TECHNIQUE :
CELAY,CEROMATIC II,
-copy milling uses a replica like wax, plastic, stone or
metal of the desired form as a guide for a milling machine.
the surface of the replica is traced by turning the pattern
and touching the patterns surface with a finger stylus. Thus
the block of appropriate size is copy milled from the
ceramic block.
-The cavity receiving the restoration should be free ofThe cavity receiving the restoration should be free of
any undercutsany undercuts..
-The pro-inlay is scanned with a scanning device and a
coarse diamond coated disc (124mm grain size)

66. simultaneously roughens out the shape of the
restoration. A fine white powder is applied to the
inlay and the scanning is done again using a
smooth disc and fissured and tapered burs.
- matching fine diamond discs and burs (60-70 mm
thick) refine the shape of the gross ceramic
restoration.
Once the white powder is completely taken off, the
milling is considered to be complete. Stains and
glazes may be added before the restoration is
etched and silanised. Copy milling takes aboutCopy milling takes about
20-30 minutes20-30 minutes..

67. CAD – CAMCAD – CAM
RESTORATIONSRESTORATIONS

68. STAGES IN CAD- CAM FABRICATIONSTAGES IN CAD- CAM FABRICATION ;;
1.computerized surface digitization
2.computer aided design
3.computer assisted manufacturing
4.computer aided esthetics
5.computer aided finishing

70. Mormann and BrandestiniMormann and Brandestini was the first ones to use cad-
cam device in 19881988.the first model which came was called
cerec I.
--CEREC ICEREC I (1988)(1988)
-cannot prepare the occlusal anatomy of the preparation .
-camera not good
--CEREC –II: ( 1994)CEREC –II: ( 1994)
-They had better image processing systems .
-it also has a cylindrical diamond stone which is able to
finish off undercuts at buccal extensions
-occlusal anatomy could be produced here
disadvanatage-
- has many parts ,so the operator had to move around
-impression not good
-marginal fit not good.

71. • CEREC 3 :CEREC 3 :
-different parts could be magnified in detail
• more finer details noted
• disadvantage: not capable of producing
margins of restoration
• CEREC 3-DCEREC 3-D
• marginal fit good
• contacts can be chosen
• 3 dimensionally movable camera

72. CERECCEREC IIII CEREC IIICEREC III

73. CAVITY CONSIDERATION FOR CAD- CAM :
- NNo convexitieso convexities should be present on the pulpal and
gingival walls .
-The occlusal step should be 1.5mm – 2mmocclusal step should be 1.5mm – 2mm in depth
- Isthmus should be at least 1.5mmIsthmus should be at least 1.5mm wide to decrease the
possibility of fracture of the restoration.
-Buccal and lingual walls of the preparation mayBuccal and lingual walls of the preparation may
converge towards the occlusal.converge towards the occlusal.
-This feature is unique to cerec systems as it canunique to cerec systems as it can
automatically block out any undercutsautomatically block out any undercuts during optical
impression.

74. -axial walls should be straightaxial walls should be straight and not follow the convex
contour of the proximal surface of the tooth
-no cavo surface or marginal bevels should be given.no cavo surface or marginal bevels should be given.
VARIOUS INGOTS USED FOR MACHINABLE
CERAMICS ARE :
1.cerec vitablocks mark I1.cerec vitablocks mark I :its composition strength are
similar to that of feldspathic porcelain. Used first with cerec
system.
2.2. Cerec vita blocks mark II:Cerec vita blocks mark II:
high strength feldspathic porcelain with grain size finer than
that of mark I composition.
-less abrasive wear of the opposing tooth

75. • 3.Dicor Mgc:3.Dicor Mgc:
glass ceramic with fluorosilicate mica crystals in a glass
matrix.flexural strength higher than castable dicor and
cerec systems.
• softer and less abrasive than cerec vitablocks mark I ,but
not as much as cerec vita blocks mark II.

76. ADVANCES IN ALL CERAMICADVANCES IN ALL CERAMIC
RESTORATIONSRESTORATIONS
• Procera
• Shrink free ceramic
• Cad-cim restoration
• Copy milling with bcelay on extracted
teeth
• Porcelain inlays
• Porcelain veneers

77. conclusionconclusion