brief description about pressable ceramicsCONTENTS: • Introduction • Definition For Dental Ceramics • Definition For Pressable Ceramics • History • Various All Ceramic Systems • Classification • Pressable Ceramics • History • Generation Of Pressable Ceramics • Cerestore – Development Fabrication Advantage Disadvantage 2 3. IPS Empress - Materials And Composition Special Furnace Fabrication Advantage Disadvantage IPS Empress 2- INDICATION Properties Fabrication Method Advantage Disadvantage IPS Emax Press - Microstructure Composition Properties OPC 3G- Development Indication Properties 3 4. INTRODUCTION There have been significant TECHNOLOGICAL advances in the field of dental ceramics over the last 10 years which have made a corresponding increase in the number of materials available. Improvements in strength, clinical performance, and longevity have made all ceramic restorations more popular and more predictable 4 5. DEFINITION FOR DENTAL CERAMICS⁶ An inorganic compound with non metallic properties typically consisting of oxygen and one or more metallic or semi metallic elements (e.g ;Aluminium, Calcium, Lithium, Mangnesium, Potassium, Sodium, Silicon, Tin , Titanium And Zirconium)that is formulated to produce the whole or part of a ceramic based dental prosthesis 5 6. DEFINITION FOR PRESSABLE CERAMICS ⁶ • A ceramic that can be heated to a specified temperature and forced under pressure to fill a cavity in a refractory mold 6 7. HISTORY OF DENTAL CERAMICS ⁶ • 1789-first porcelain tooth material by a French dentist De Chemant • 1774- mineral paste teeth by Duchateau in England • 1808-terrometallic porcelain teeth by Italian dentist Fonzi • 1817- Planteu introduced porcelain teeth in US • 1837- Ash developed improved version of porcelain teeth 7 8. • 1903 – Dr.Charless introduced ceramic crowns in dentistry he fabricate ceramic crown using platinum foil matrix and high fusing feldspathic porcelain excellent esthetics but low flexural strength resulted in failure • 1965- dental aluminous core Porcelain by Mclean and Huges • 1984- Dicor by Adair and Grossman 8 9. 9 10. VARIOUS ALL CERAMIC SYSTEMS  Aluminous core ceramics  Slip cast ceramics  Heat pressed ceramics  Machined ceramics  Machined and sintered ceramics  Metal reinforced system 10 11. MICROSTRUCTURAL CLASSIFICATION⁵ Category 1: Glass-based systems (mainly silica) Category 2: Glass-based systems (mainly silica) with fillers usually crystalline (typically leucite or a different high-fusing glass) a) Low-to-moderate leucite-

1. 1

2. CONTENTS: • Introduction
• Definition For Dental Ceramics
• Definition For Pressable Ceramics
• History
• Various All Ceramic Systems
• Classification
• Pressable Ceramics
• History
• Generation Of Pressable Ceramics
• Cerestore – Development
Fabrication
Advantage
Disadvantage
2

3. IPS Empress - Materials And Composition
Special Furnace
Fabrication
Advantage
Disadvantage
IPS Empress 2- Indication
Properties
Fabrication Method
Advantage
Disadvantage
IPS Emax Press - Microstructure
Composition
Properties
OPC 3G- Development
Indication
Properties 3

4. INTRODUCTION
There have been significant technological advances in
the field of dental ceramics over the last 10 years which
have made a corresponding increase in the number of
materials available. Improvements in strength, clinical
performance, and longevity have made all ceramic
restorations more popular and more predictable
4

5. DEFINITION FOR DENTAL CERAMICS⁶
An inorganic compound with non metallic properties typically
consisting of oxygen and one or more metallic or semi
metallic elements (e.g ;Aluminium, Calcium, Lithium,
Mangnesium, Potassium, Sodium, Silicon, Tin , Titanium And
Zirconium)that is formulated to produce the whole or part of
a ceramic based dental prosthesis
5

6. DEFINITION FOR PRESSABLE CERAMICS ⁶
• A ceramic that can be heated to a specified temperature and
forced under pressure to fill a cavity in a refractory mold
6

7. HISTORY OF DENTAL CERAMICS ⁶
• 1789-first porcelain tooth material by a French dentist De
Chemant
• 1774- mineral paste teeth by Duchateau in England
• 1808-terrometallic porcelain teeth by Italian dentist Fonzi
• 1817- Planteu introduced porcelain teeth in US
• 1837- Ash developed improved version of porcelain teeth
7

8. • 1903 – Dr.Charless introduced ceramic crowns in dentistry he
fabricate ceramic crown using platinum foil matrix and high
fusing feldspathic porcelain excellent esthetics but low
flexural strength resulted in failure
• 1965- dental aluminous core Porcelain by Mclean and Huges
• 1984- Dicor by Adair and Grossman
8

9. 9

10. VARIOUS ALL CERAMIC SYSTEMS
 Aluminous core ceramics
 Slip cast ceramics
 Heat pressed ceramics
 Machined ceramics
 Machined and sintered ceramics
 Metal reinforced system
10

11. MICROSTRUCTURAL CLASSIFICATION⁵
Category 1: Glass-based systems (mainly silica)
Category 2: Glass-based systems (mainly silica) with fillers usually crystalline
(typically leucite or a different high-fusing glass)
a) Low-to-moderate leucite-containing feldspathic glass
b) High-leucite (approx. 50%)-containing glass, glass-ceramics (Eg: IPS
Empress)
c) Lithium disilicate glass-ceramics (IPS e.max® pressable and machinable
ceramics)
Category 3: Crystalline-based systems with glass fillers (mainly alumina)
Category 4: Polycrystalline solids (alumina and zirconia)
11

12. PRESSABLE CERAMICS
12

13. History
• Early 1990 - pressable glass ceramic(ips impress) containing
approximately 34 vol% leucite was introduced that provide a
strength and marginal adaptation similar to dicor glass
ceramic but do not require no specialized crystallization
treatment
• They are not indicated to produce FPD
13

14. • Late 1990- Ips Empress 2 more fracture resistant with 70 vol %
Lithia Disilcate crystal was introduced
• used for 3 unit FPD up to premolar
• The fracture toughness of Ips Empress 2 glass ceramic(3.3mpa
m⅟2)is 2.5 times grater than that of Ips Empress glass ceramic
(1.3 mpa m⅟2)
14

15. VARIOUS GENERATION OF PRESSABLE
CERAMICS
BY PRESURE MOLDING AND SINTERING
• Shrink free ceramics –
e.g.; cerestore
alceram
BY HEAT TRANSFER MOLDED
• Leucite reinforced glass ceramic- e.g.; Ips empress
Optec opc
• Lithia reinforced glass ceramic – e.g.; Ips empress 2
Ips emax empress
15

16. CERESTORE
16

17. Development
• - developed by the Coors Biomedical Co. and later sold to
Johnson & Johnson.
• Shrink free ceramic
composition
• Consist of – Al₂O₃ and MgO mixed with barium glass frits
• Flexural strength approx 150 Mpa
17

18. FABRICATION
• Transfer molding process
• The Cerestore crown was veneered with conventional
porcelains
18

19. Preheated ,uncured molding compound is placed in the transfer
pot
19

20. • A hydraulically powered
plunger pushes the molding
compound through the
sprue in to the preheated
mould cavity
• The mold remain closed
until the material inside is
cured or cooled
20

21. • The mold is split to free the
product with the help of
ejector pins
21

22. • The splash and sprue
material is trimmed off
22

23. ADVANTAGE OVER PJC
• The use of a shrink-free ceramic coping formed on an epoxy
die by a transfer molding process overcame the limits and
firing shrinkage of conventionally produced aluminous
porcelain jacket crown.
• On firing transformation produces Magnesium Aluminate
spinel which occupies a greater volume than the original
mixed oxides compensate for the conventional firing
shrinkage
23

24. ADVANTAGE
• Good dimensional stability
• Better accuracy of fit and marginal integrity
• Esthetics
• Biocompatible
• Low thermal conductivity
• Low coefficient of thermal expansion
24

25. DISADVANTAGE
• Complexity of the fabrication process
• Need for specialized fabrication equipment
• Inadequate flexural strength
• Poor abrasion resistance
• High clinical failure rates
25

26. ALCERAM
• Modification of cerestore with high flexural strength is
marketed under the name alceram
26

27. IPS EMPRESS⁴
27

28. DEVELOPMENT
• First described by wohlwend and scharer
• The IPS-Empress system was developed at the University of
Zurich, Zurich, Switzerland, in 1983.
• Ivoclar Vivadent took over the development project in 1986
and presented it to the profession in 1990.
28

29. • First generation heat-pressed ceramics contain between 35
and 45 vol % Leucite as crystalline phase
• Flexural strength and fracture toughness values that are about
two times higher than those of feldspathic porcelains
29

30. MICROSTRUCTURE AND COMPOSITION
COMPOSITION IN WT%:
• 63% - sio₂,
• 17.7 % - AI₂0₃
• 11.2 % - K₂O,
• 4.6 % - Na₂O,
• 0.6 % - B₂O₃
• 0.4% - CeO₂
• 1.6% - CaO,
• 0.7 % - BaO,
• 0.2 % - TIO₂,
• The crystalline part of the
ceramic consists of leucite
crystals,
30

31. PROPRETIES
• Flexural strength - 112±10 mpa
• Fracture toughness - 1.3±0.1 mpa˙m⅟2
• Thermal exoansion coefficient - 15.0±0.25 ppm/ ⁰c
• Chemical durrability - 100-200 ug/cm²
• Pressing temperature - 1180 ⁰c
• Veneering temperature - 910 ⁰c
31

32. USES
• Laminate veneers and full crown for anterior teeth
• Inlays ,onlays and partial coverage crowns
32

33. Ingots
• Leucite containing Glass ceramic provided as core ingots that
are heated and pressed until the ingot flows into a mold
• It contains a higher concentration of leucite crystals that
increase the resistance to crack propagation
• The hot pressing process occurs over a 45 min period at a
high temperature to produce the ceramic substructure
• This crown can be either stained and glazed or built up using
a conventional layering technique
33

34. A SPECIAL FURNACE - (EMPRESS EP 500)
34

35. AUTOMATIC FURNACE
35

36. A SPECIAL FURNACE - (EMPRESS EP 500)
contains an:
• enlarged heat dome,
• a pneumatic pressure system,
• a reducing valve,
• a manometer to control the pressure;
• an inductive displacement transducer is mounted on top of
the furnace and is connected to the pneumatic plunger
36

37. 37

38. FABRICATION
• The crown or inlay was waxed and placed on a specially
designed cylindrical crucible former and invested using a
phosphate-bonded investment.
• The mold was heated in a burnout furnace to 850°C.
• The cylindrical opening into the mold was filled with a ceramic
ingot and an Al₂O₃ pushing rod.
• The assembly was then placed into the preheated furnace
38

39. • The inlays must be waxed
and placed on a specially
designed cylindrical crucible
former
• Ceramic ingots are
preshaded and
precerammed.
• For the inlay technique,
translucent material is used.
39

40. • After filling the cylindrical opening with an already
preheated ceramic ingot and an AL₂O₃ pushing rod, the cast
must be placed into the preheated Empress furnace.
• The aluminium oxide pushing rod is used to transfer the
pressure to the ceramic material
40

41. • After the press procedure, the inlays are devested and
prepared for further treatments
41

42. • The occlusal surface and the inner surface can be covered
with a thin layer of surface stains. The occlusal surface will be
covered with a glaze
42

43. • Inlays can be made more simply and have good marginal
integrity when placed
43

44. • The main advantage of the IPS-Empress system is that through the
injection-molding process, which involves the use of heat and
pressure,
• The leucite crystals incorporated in the material create barriers that
counteract the buildup of the tensile stresses that predispose to
formation of micro cracks.
• Thus the added leucite crystals improve flexural strength and
fracture resistance through so-called dispersion strengthening.
44

45. • The crystals act as “roadblocks” in preventing crack
propagation, so that the restoration does not undergo
catastrophic failure during function.
• In addition, the combination of heat and pressure used in the
casting process reduces the amount of ceramic shrinkage and
results in higher flexural strength.
45

46. AUTOMATIC FURNACE
• Rate of temperature increase varied from 5°C to 2O⁰C/min,
• Furnace can be heated to 1,200°C,
• Holding time at the final temperature varied from 0 to 60
minutes.
• If the pneumatic plunger does not continue to move more
than 0.3 mm/min, the pressure maintenance time will be
activated.
46

47. • A pressure maintenance of 1 to 4 minutes is necessary
depending on the thickness of the cavity that has to be filled;
the time can be varied from 1 to 20 minutes,
• The press procedure is performed in a vacuum, and the
beginning and ending points for the vacuum application can
be programmed
47

48. • When the start button is pushed, the furnace heats up
automatically to the programmed press temperature
(1,150°C),
• After a 20-minute holding time at this temperature the press
procedure was activated and the then-plastic glass-ceramic
material was pressed (0.3 to 0.4 Mpa) into the mold.
• The mold was filled with the glass-ceramic material and the
furnace stopped automatically.
• The ceramic restorations were devested and prepared for
further treatments
48

49. ADVANTAGE
• Lack of metal
• Translucent ceramic core
• Moderately high flexural strength
• Fracture resistance
• Excellent fit
• Excellent esthetics
• Etchable
49

50. DISADVANTAGE
• Potential to fracture in posterior areas
• Need to use resin cement to bond the crown
micromechanically to tooth structure
50

51. IPS EMPRESS 2
51

52. IPS EMPRESS 2
• Second generation of heat pressed dental ceramics
• contain about 65 vol % lithium Disilcate as the main crystalline
phase.
• The material is pressed at 920⁰c and layered with a glass containing
some dispersed apatite crystals
• Their strength is more than twice that of first generation leucite-
reinforced all-ceramics and their good performance has led to their
expanded use to restorations produced by machining.
52

53. MICROSTRUCTURE HEAT-PRESSED
LITHIUM DISILCATE GLASS-CERAMIC
53

54. PHYSICAL PROPERTIES
• Flexural strength - 400±40 mpa
• Fractural toughness - 3.3±0.3 mpa˙m⅟2
• Coefficient of thermal expansion - 10.6+0.25 ppm/ ⁰c
• Chemical durability - 50 ug/cm²
• Press temperature - 920⁰c
• Firing temperature - 800⁰c
54

55. INDICATIONS
• Anterior and posterior Crown
• Anterior three unit FPDs
• Inlays and onlays
• Premolar FPD
Other application: cosmopost and Ips empress cosmos ingot –
core built up system with the prefabricated zircon oxide root
canal posts and the optimally coordinated ingot
55

56. FABRICATION PROCEDURE
• Wax the restoration to final contour ,sprue, and invest as with
conventional gold casting
• If the veneering technique is used, only body porcelain shape
is used
• Heat the investment to 800⁰c to burn out the wax pattern
• Insert a ceramic ingot of the appropriate shad and alumina
plunger in the sprue and place the refractory in the special
pressing furnace
56

57. • After heating to 1165⁰c, the softened ceramic is slowly
pressed into the mold under vacuum
• After pressing recover the restoration from the investment by
airborne particle abrasion ,remove the sprue and refit in to
the die .
• Esthetics can be enhanced by applying an enamel layer of
matching porcelain or by adding surface characterization
57

58. 5
1.Wax and invest 2.Press ceramic
4.Framework 5.Veneer buildup 6.Final Bridge
3.Divest pressing

59. ADVANTAGE
• Excellent translucency corresponding to natural teeth
• High mechanical strength
• Superior opalescence/ fluorescence
• Wear comparable to natural dentition
• Low bacterial adhesion
• Opacity
• Controlled crystallization
• Can be bonded as well as conventionally cemented
• Superior fracture toughness
59

60. IPS EMAX PRESSⁱ
60

61. IPS e.max is an all-ceramic system that consists of the
following five components:
• • IPS e.max Press (lithium Disilcate glass-ceramic ingot for the
press technique)
• • IPS e.max ZirPress (fluorapatite glass-ceramic ingot for the
press-on technique)
• • IPS e.max CAD (lithium Disilcate glass-ceramic block for the
CAD/CAM technique)
• • IPS e.max Zircon (zirconium oxide block for the CAD/CAM
technique)
• • IPS e.max Ceram (fluorapatite veneering ceramic)
61

62. INGOTS
• IPS e.max Press is a lithium Disilcate glass ceramic ingot for
use with the press Technique
• The ingots are available in two degrees of opacity
62

63. 63

64. • These ingots have been developed on the basis of a lithium silicate
glass ceramic .
• The ingots are produced by bulk casting.
• A continuous manufacturing process based on glass technology
(casting/pressing procedure) is utilized in the manufacture of the
ingots.
• This new technology uses optimized processing parameters, which
prevent the formation of defects (pores, pigments, etc) in the bulk
of the ingot.
64

65. MICROSTRUCTURE
• The microstructure of IPS e.max Press consists of lithium
Disilcate crystals (approx. 70%), which are embedded in a
glassy matrix.
• Lithium Disilcate, the main crystal phase, consists of needle-
like crystals
• The crystals measure 3 to 6 μm in length.
65

66. COMPOSITION
Standard composition: (in wt %)
• SiO₂ 57.0 – 80.0
• Li₂O 11.0 – 19.0
• K₂O 0.0 – 13.0
• P₂O₅ 0.0 – 11.0
• ZrO₂ 0.0 – 8.0
• ZnO 0.0 – 8.0
• other oxides 0.0 – 10.0
• +coloring oxides 0.0 – 8.0
66

67. INDICATIONS
• Thin veneers (0.3 mm)
• Inlays , onlays, occlusal veneers
• Crowns in the anterior and posterior region
• Bridges in the anterior and premolar region
• Implant superstructures
• Hybrid abutments and abutment crowns
67

68. PHYSICAL PROPERTIES
68

69. FLEXURAL STRENGTH
69

70. • The strength values of IPS e.max Press and IPS Empress2,
which are higher than IPS Empress, are attributable to the
composition of these materials (lithium disilicate crystals).
70

71. FRACTURE STRENGTH OF ANTERIOR BRIDGES
• The fatigue strength of IPS e.max Press by far surpasses the
maximum load that may be exerted on the material under
natural conditions.
• It can be assumed that three-unit anterior bridges made of
IPS e.max Press are long lastingly resistant to fracture, if
constructed according to the Instructions for Use
71

72. 72

73. FRACTURE STRENGTH OF THREE-UNIT
POSTERIOR BRIDGES
• The highest fracture strength was measured for anatomically
pressed bridges.
• The fracture strength of veneered frameworks is higher than
that of frameworks without veneering.
• This increase in fracture load may be attributed to the size of
the cross-section, which is larger in veneered frameworks
than in non-veneered ones.
73

74. FRACTURE STRENGTH OF PARTIAL CROWNS
• The fracture strength measured in the posterior region did
not significantly differ from that of the natural, unprepared
teeth.
MARGINAL FIT
• Marginal gap in IPS emax empress - 29.22 um
74

75. 75
BIOCOMPATIBILITY
• All-ceramic materials are known for their high levels of
biocompatibility
CYTOTOXICITY
• No cytotoxic potential has been observed in IPS e.max Press
SENSITIZATION, IRRITATION
• Ceramic has no or, compared to other dental materials very
little potential to cause irritation or sensitizing reactions.

76. ADVANTAGES
• Cost-effective, esthetic alternative to full cast crowns
• High esthetics, even with different preparation shades
• Wide range of indications from thin veneers to three unit
bridges
• Highly esthetic alternative to ZrO2-supported crowns
• Self-adhesive or conventional cementation of crowns and
bridges
76

77. OPC 3G
77

78. DEVELOPMENT
• Third generation pressable ceramics
• Porcelain is twice the stregnth of previous generation pressed
ceramics
• Size of leucite crystals reduced and improved its distribution
without reducing the total crystalline content
78

79. PROPERTIES
• Optimally pressed cermic is comprised of combination of
materials that enhance ability to mimic natural dentition
• Compressive strength -23,000psi
• Provides high degree of fit to the tooth
• Increase load bearing capacity
79

80. CEMENTATION
• Variolink II – DUAL CURING
• Variolink veneer- LIGHT CURING
• Multilink automix
• Speed cem
• Variolink speed
80

81. MULTILINK® AUTOMIX
• is a universal, self-etching composite system that is directly
applied without mixing.
• Multilink Primer seals the dentin and ensures a good
marginal seal as well as high bonding strength.
81

82. Multilink speed
Standard composition (in wt%) Base Catalyst
• Dimethacrylates 23.3 26.0
• Ytterbium trifluoride 45.2
• Co-polymer - 22.6
• silicon dioxide 75.0 2.2
• Adhesive monomer - 3.1
• Initiators, stabilizers and pigments 1.7 0.9
82

83. 83

84. Variolink II
Monomer matrix:
• Bis gma
• Urethrane dimethacrylate
• Triethylene glycol dimethacrylate
Inorganic fillers :
• BARIUM GLASS
• Yettrium trifluoride
• Ba-al fluorosilicate glass
• Spheroid mixed oxide
Additional contents:
Catalyst ,stabilisers , pigments 84

85. SPEED CEM
Self adhesive , self curing resin cement with light curing
option
Advantage
• No phosphoric acid etching
• No primer , bonding agents or adhesives for enamel and
dentin
• Good bonding values
• High strength
85

86. 86

87. Standard composition (in wt%) Base Catalyst
• Dimethacrylates 23.3 26.0
• Ytterbium trifluoride 45.2
• Co-polymer - 22.6
• silicon dioxide 75.0 2.2
• Adhesive monomer - 3.1
• Initiators, stabilizers and pigments 1.7 0.9
87

88. 88

89. 89

90. • Flexural strength – force per unit area at the point of fracture of a
test specimen subjected to flexural loading
• Tensile strength- tensile stress at the point of fracture
• Fracture toughness – the critical stress intensity factor at the
beginning of rapid propagation in a solid containing a crack known
of shape and size
• Coefficient of thermal expansion - change in length per unit of
original length of a material when its temperature raised to 1⁰k
90

91. COMPARISION OF IPS EMPRESS IPS
EMPRESS 2 IPS EMAX EMPRESS
91

92. Ips empress Ips empress 2 Ips emax press
Microstructure leucite crystals lithium Disilcate glass
ceramic
lithium Disilcate glass ceramic
crystals measure 3 to 6 μm in
length.
Indication •single-unit
restorations
•Crown
•Anterior 3 unit FPDs
•Inlays and onlays
• veneer , Inlays/onlays,
• Crowns and bridges in the
anterior and posterior region,
• Implant superstructures,
• Hybrid abutments and
abutment crowns
Properties Flexural strength
- 112±10 mpa
Fracture toughness
-1.3±0.1mpa˙m⅟2
Thermal expansion
coefficient -
15.0±0.25ppm/⁰c
Chemical durrability
-100-200 ug/cm²
Pressing temp
- 1180 ⁰c
Veneering temp
- 910 ⁰c
Flexural strength
- 400±40 mpa
Fractural toughness
- 3.3±0.3 mpa˙m⅟2
Coefficient of thermal
expansion -10.6+0.25
ppm/ ⁰c
Chemical durability
- 50 ug/cm²
Press temperature
- 920⁰c
Firing temperature
- 800⁰c
•Flexural strength – 400±40
mpa
•Fracture toughness 2.5 –
3.0 Mpa.m⅟₂
•Coefficient of thermal
expansion – 10.55±0.35
10‾⁶k‾ ˡ
•Chemical solubility 40±10
ug/cm²
92

93. Advantage •Translucent
ceramic core
•Moderately
high flexural
strength
•Fracture
resistance
•Excellent fit
esthetics
•Excellent translucency
• High mechanical
strength
•Superior opalescence/
fluorescence
•Wear comparable to
natural dentition
•Low bacterial adhesion
•Cost-effective,
• High esthetics,
•Self-adhesive or
conventional
cementation of crowns
and bridges
93

94. CONCLUSION
• Restorative dentistry faces new challenges in adopting
emerging technologies related to dental materials and in
meeting patient demand . with the increasing clinical success
of such alternative restorative materials, the use of metallic
restoration in the posterior teeth is declining .
94

95. REFERENCES
1. Ips emax press –scientific documentation ivocular vivadent
2. Ceramics for dental application- a review;isabella denry ,materials -
January 2010
3. Longevity and clinical performance of Ips empress ceramic restorations a
literary review jean François brochu –journal of Canadian dental
association April 2002,vol.68,no.4
4. Heat pressed ceramics –j.k.dong –international journal of prosthodontics
–vol.5 number 1 ,1992
5. Ceramics in dentistry – narashima ragavan ,
6. Philips science of dental material -11th edition –kenneth j anusavice
95