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7. Definition of Ceramics
• Compounds of one or more metals with a non-
metallic element, usually oxygen, they are formed
of chemically and biochemically stable substances
that are strong, hard, brittle and inherent non
conductors of thermal and electrical energy.
• In an inorganic compound with a non-metallic
properties consisting oxygen and one or more
metallic or semi metallic elements that is
formulated to produce whole or a part of ceramic
based dental prosthesis.www.indiandentalacademy.com
8. Composition of Dental Porcelain
• Feldspar: It is a precursor of common clay.
• Natural feldspar is a mixture of albite
(Na2Al2Si6O16) and ortho clayse microcline
(K2Al2Si6O16) with three crystalline cords.
• It is a crystalline and opaque with an indefinite
color between gray and pink.
• Chemically it is designated as potassium
aluminium silicate.
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9. • On heating it fuses at an about 1290°C.
• Potassium feldspar and sodium feldspar are
naturally occurring materials composed of Potash
(KO2), Soda (Na2O), Alumina (Al2O3) and Silica
(SiO2)
• Potash feldspar is used in most dental porcelains
due to its increased resistance to pyroplastic flow
and increased viscosity.
• Potassium feldspar is mixed with various metal
oxides and fired at high temperatures, it can form
a leucite and a glass phase that will soften and
flow slightly.
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10. Silica
• Pure quartz crystals (SiO2) are used in dental
porcelain as strengthener of 13-14%.
• Silica can exist in 4 different forms.
- Crystalline quartz
- Crystalline trydynite.
- Crystalline crystobalite.
- Non crystalline fuse silica.
• It prevents the crown from slumping during the
liquid phase.
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11. • Johns (1970) determined the strength of
porcelain bodies containing 10% by weight
of quartz and found a marked reduction in
the flexural strength of the fired bodies.
• He suggested that the high coefficient of
thermal expansion and inversion of quartz
crystals were the determining factors in the
lower strengths observed.
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12. Kaolin
• It serves as a binder and is included in small
concentration of 4-5%.
• It gives a property of opaqueness.
• When mixed with water it forms a sticky mass
alloying unfired porcelain to be easily worked and
moulded.
• When subjected to high heat during firing it
adheres to the frameworks of quartz particles and
shrinks considerably.
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13. Colour Pigments
• The colour pigments are added to the
porcelain mixture are called ‘color frits’
• To produce lifelike dentin and enamel
colors and help the finished restoration to
resemble the natural teeth color.
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14. Colour pigments used in dental
porcelain
• Titanium oxide – Yellow-brown shade.
• Indium – Yellow/Ivory.
• Iron oxide & Nickel oxide – Brown
• Copper / Chromium oxide – Green
• Chromium-tin / chromium-alumina – Pink
• Iron oxide / Platinum – Grey.
• Manganese oxide – Lavender.
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15. Opacifying agents
• Opacifying agents generally consists of metal
oxides 8%-15% and grown to a very fine
particle size (<5µm) to prevent a speckled
appearance in porcelain.
• Commonest oxides used are-
a. Zirconium oxide.
b. Cerium oxide.
c. Titanium oxide.
d. Tin oxide.
e. Zircon oxide. www.indiandentalacademy.com
16. Stains and Color modifiers
• Stains are generally low fusing colored porcelains
used as surface colorants or to provide imitate
markings, enamel check lines, decalcification
spots, fluoresced areas etc.
• Color modifiers are less concentrated than stains
used to obtain gingival affect or high light body
colors and are best used at the same temperature
of dental porcelains.
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17. Glass modifiers
• Potassium, sodium and calcium oxides are the
most commonly used glass modifiers.
• It acts as a fluxes by interrupting the integrity of
silica tetrahedra network.
• More glass modifiers and thus low firing
temperatures.
• High proportions of glass modifiers tends to
reduce the resistance of the applied glaze.
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18. Glazes and Add-on Porcelain
• The main purpose of glaze is to seal the
open pore in the surface of the fired
porcelain.
• Dental glazes consist of colorless low
fusing porcelains which can be applied to
the surface of fired crown to produce a
glazy surface.
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19. • Glazing can be two types:
1. Self glazing (Autoglazing).
In self glazing procedure an external glaze
layer is not applied but the completed
restoration itself is subjected to glazing
2. Add on glazing
In add on glazing an external glaze layer is
applied on the surface.
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20. Other additions in dental
porcelain
• Boric oxide (B2O3): It serves as a glass
modifiers as well as glass former.
• Alumina (Al2O3).
• Magnesium oxide (MgO).
• Lithium oxide (Li2O): May be added as
additional fluxing agent.
• Phosphorous pentoxide (P2O5): added to
induce opalescence.
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22. Properties of Porcelain
• Compressive strength – 50,000psi
• Tensile strength – 5,000 psi
• Shear strength – 16,000 psi
• Elastic modulus – 10x106 psi
• Knoop hardness no. – 460
• Linear coefficient of TE – 12x10-6/°C
• Specific gravity - 2.2-2.3
• Thermal conductivity – 0.0050°C/cm
• Linear shrinkage - High fusing – 11.5%
- Low fusing – 14.0%
• Refractive index – 1.52 – 1.54
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23. Recent Advances
All Ceramic restorations :
These newer all ceramic restorations have lower
incidence of clinical fractures to three important
reasons
1. Made of stronger materials and include better
fabrication techniques.
2. They can be etched and bonded t o the underlying
tooth structure with new dental adhesives
3. Greater tooth reduction that provides lab technicians
with enough room to create thicker and stronger
restoration
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27. Conventional powder slurry ceramics
• These ceramic products are supplied as powders to
which the technician adds water to produce slurry,
which is built up on a die material to form the
contours of the restorations.
• The powder are available in variety of shades and
translucencies, also with stains and glazes.
optec HSP :
Developed by Jeneric Inc / USA sometimes before
it was established in the Germany market by
Keppeler and Whor.
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28. Optec ceramic is a feldspathic composition glass filled
with crystalline leucite (potassium aluminum silicate )
The leucite concentration in optec was 50.6% > IPS
impress ceramic (23.6% / wt.% or 41.3 wt.%)
This ceramic has high level of leucite hence got a greater
strength than traditional feldspathic porcelain: Leucite is
dispersed in a glassy matrix.
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29. Leucite and glass fuses together during
firing at a temperature of 1020 C .
Increased wear of natural tooth i.e., seen
because of increased leucite content (high
abrasive property)
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31. Advantages
More translucent than alumina core crowns
Good flexural strength – 146 mpa.
Does not require special processing
equipment.
Lack of metal or opaque sub-structure
Can be etched to allow optimum bonding to
Enamel or Dentine
Restorations fit accurately
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32. Disadvantages
Increased wear of opposing teeth
Potential marginal inaccuracy caused
by porcelain sintering shrinkage
Potential to fracture in posterior teeth
Require special die material
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34. Duceram LFC
Hydrothermal low fusing ceramic
It is composed of an amorphous glass
containing hydroxyl ions.
These hydroxyl ions allow a greater flexural
strength due to ion exchange mechanism,and
also promote healing of surface micro cracks.
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35. The restoration made in two layers– the
base layer is Duceram metal ceramic (a
leucite containing porcelain)wich is placed
on refractory die using powder slurry
technique and backed at 930 deg.C.
Second layer is applied over balsal layer
using same tech. and baked at 660 deg. C.
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38. Advantages
Good flexural strength – 110 mpa.
Greater density
Greater fracture resistance
Decreased abrasion of natural tooth
Disadvantages
Need a special die material
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39. Castable Ceramics
This product is supplied as solid ceramic ingots.
These ceramic are used to fabricate cores and
full contour restorations using the lost wax and
centrifugal casting tech.
Generally one shade of material is available
which is covered by the conventional
feldspathic porcelain or it can be stained to
obtain proper shading characterization of the
final restoration.
eg: Dicor (Dentsply)
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40. Dicor
• The use of glass ceramics in dentistry was first
proposed by Macculloch in 1968.
• The first description of Dicor Castable ceramic was
given by Adari & Grossman in 1984 and was
marketed by Dentsply Int
• This is a poly-crystalline glass ceramic material,which
is casted in a similar manner to alloy castings.
• Once the glass crown is cast(at about 1350 deg. C) it is
then heat treated at 1075 deg. C for 10 hrs.this heat
treatment is known as “Ceramming”
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41. • This causes partial crystallisation of tetrasilicic
mica crystals to produce a glass ceramic
material.
• These crystals function in two ways –
– A) creating a relatively opaque material out of the
initially transparent glass crown
– B) they significantly increase the fracture resistance
and strength of the ceramic
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43. Dicor plus:
It is a shaded feldspathic porcelain veneer
applied to the Dicor substrate for
fabrication of Willi’s glass crowns (crown
of venerred Dicor ceramic)
marginal openings of 30-60m compared
to those of metal ceramic crowns
Restoration is etched with 10%
ammonium-bifluoride
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44. Advantages
Good flexural strength (152 mpa.)
Good fracture resistance.
Less abrasion of natural tooth
Can be etched to bond to natural tooth.
Easy adjustments.
Inherent resistance to plaque accumulation
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45. •Disadvantages
• Special investment & casting equipment is
recquired
•Uses
Inlays, Onlays
Full contour restorations or cores
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46. Pressable Ceramics
First described by Wohlwend et.al. in 1989
Commercially available as IPS Empress and Optec
OPC
The ceramic is available in the form of ingotes and is
primarily a Precerammed glass reinforced with Leucite
that prevents crack propagation wioth out significantly
diminishing its translucency
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47. Injection Molded Glass Ceramic
(IPS Empress)
IPS Empress is a precerammed glass Ceramic that is
heated in a cylinder form and injected under pressure
into a mold over 45 min. period .
The Ceramic is primarily a glass filled with crystalline
leucite (23.6%wt .colored & 41.3%wt. opaque)
produce the Ceramic sub-structure.
This crown form can be either stained and glazed or
controlled with an investment having appropriate
expansion
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48. Build up using conventional layering tech.
High concentration of Leucite crystals that
increase the resistance to crack propagation
Advantages
Lack of metal or opaque Ceramic core
Moderate flexural strength
Excellent fit of the restoration
Excellent esthetics
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49. Disadvantages
• Potential to fracture in poterior areas
• Need for special laboratory equipment
(pressing oven & die material )
• Single anterior crowns
• Inlays
• Onlays
• Veneers
Uses
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52. Optec Opc :
Leucite reinforced hot pressed ceramic.
A type of feldspathic porcelain with increased
leucite content
Supplied in the form of ingots. The restoration
is waxed , invested & placed in a specialized
mold with an aluminium plunger & ceramic
ingot is placed under the plunger .
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53. The entire assembly is heated to 1150 dgr c and
plunger is released which presses the molten
ceramic in to the mold .
The pressed ceramic is then baked & the pressed
form can be made to full contour or as a
substrate on which conventional feldspathic
porcelain can be built up .
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57. Empress 2 (E – 2 )
This system consist of 2 components
1. First component is a compressed core material of
lithium – di – silicate glass ceramic & lithium
orthophosphate crystals with a flexural strength of 350
mpa .
The scope of use of empress 2 for small bridges
&posterior teeth has widened compared to emp- 1 due
to its increased flexural strength .
2. The second component is a new layer / laminated
material comprised of a fluoraptite –glass crystals .
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58. A higher volume of crystalline phase result in incresed
strength of IPS empress –2 compared to the original
IPS empress .
The pressed ceramic material is translucent such that
the color of the underlying tooth structure is trnsmitted
through out.
The shade of the prepared tooth is determined with a
specially formulated shade guide ‘
“CHROMOSCOPE”& the restoration can be
completed in one of the 2 ways .
A) surface staining technique
B) layering technique
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59. Surface staining technique :
Used in posterior region for inlays , onlays &few
posterior crowns .
Specifically developed shading porcelain which
is painted on to the base-colored restoration .
firing cycle – 850 dgr c for 2 mins in vacume .
The shaded restoration is tried on the dentin
shaded die .
The shading may require 2-4 firings for the final
intrinsic characterization to be developed.
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60. It was developed by willi geller .
The restoration is not waxed to contour , so that
sufficient space can be provided after ceramic
pressing for the layering translucency &individual
characterization .
If in sufficient space exists a cut back of the ceramic
core is possible.
Layering technique
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61. A specifically developed porcelain with a
lower coefficient of thermal expansion is
used for layering
The incisal and enamel layers are backed
separately on the core before final stain
characterization of finishing
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62. • INFILTRATED CERAMIC
• conventional feldspathic porcelain :
• This system utilized aluminum as the core
material
• This porcelain is supplied as a two –component
system i. e. a powder (aluminum oxide /spinal
)which is fabricated into a substrate and then
infiltrated at high temperature with molten glass
infiltrate .
• The infiltrate ceramic is then veneered using the
technique .
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64. • INCERAM :
• Developed by sadoun (Paris) &sold by vita
company &was presented in 1989 for first
time.
• The powder containing fine –grained particles
of aluminum oxide and magnesium oxide is
mixed with water to form a suspension, known
as a ‘slip’.
• Slip is placed on a gypsum die and baked at
1120 dgr c for 10 hrs to produce opaque porous
core .
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65. • At this stage the material is fragile and must be
handled very carefully .
• Next appropriate shade of glass is applied to the
core and baked again at 1100 dgr c for four hrs .
• During this process the molton glass infiltrates
the porous alumina by capillary action and
increases strength of the core by 20 times .
• Aluminum oxide limits the crack propagation
and glass infiltration reduce porosity .
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67. • This core is then veneered using aluminous
veneering porcelain by convetional powder
slurry tch. To create a restoration with proper
contour .
USES
• single anterior & posterior crowns
• anterior 3- unit bridge
• implant supported bridge
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68. ADVANTAGES
• Lack of metal substrate
• Extremely high flexural strength – 450 mpa
• Strongest of all ceramic dental restoration
• Excellent fit
• DISADVANTAGES :
• Opacity of the material & hence can be used
only as core .
• Special die material &high temp oven is required
• Unstable for conventional acid etching .
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70. TECH CERAM :
• It is developed by a British team (tech ceram
ltd,Shipley , u.k)
• A thin (0.1 – 1mm)alumina core base layer is
produced using a thermal spray tech ,resulting in
a density 80 – 90 % .
• Optimum strength &translucency are achieved
by a sintering process at 1170 dgr c .
• The range of base layer thickness makes this tech
versatile &appropriate to a range of restoration
types .
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71. • Subsequent reproduction of esthetics is achieved
by incremental application of a range of
specially developed porcelain in the traditional
manner .
• The inner surface is rough &according to
manufactures , it does not require etching or
silane bonding . GIC or dual core resin –
composite luting agent are recommended .
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72. MACHINABLE CERAMICS :
• Supplied as ceramic ingots available in various
shades .
• These ingots are placed in a machinable
apparatus to produce desired contours .
• Restoration is checked for fit on the tooth .
• Occlusal adjustment is done followed by
polishing etching and bonding the restoration to
the prepared tooth .
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73. • In september 1987 the ceramic ingots were
introduced in to market .
• Frist generation of these blocks cerec vitabloc
mark 1. Developed by vita in close co-opration
with professor hormann .
• CEREC VITABLOC MARK 1 :
• Coposition, strength &wear chreterstics similar
to that of porcelain .
• Used for porcelain fused metal restoration .
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74. • CEREC VITABLOC MARK 2:
• Introduced in 1991 .
• Incresed strength & has finer grain size than
mark 1 composition .
• Produces less abrasive wear of opposing tooth .
• DICOR MGC :
• it is composed of fluoro silicate mica crystals in
glass matrix .
• It has greater flexural than cast dicore .
• Produce less abrasive wear than mark 1 more
than mark 2 .
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76. • CELAY :
• fine grain size feldspathic porcelain similar to
vita bloc mark 2.
• Requires a celay copy milling system .
• Properties of these feldspathic ceramics are:
• Machinability
• High degree of esthetics
• Mechanical properties like strength &wear
resistance are similar to natural tooth .
• It can easly etched to produce retentive surface
for adhasive cementation .
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78. CAD – CAM TECHNOLOGY
• It is termed as computer aided designing and
computer aided machining
• CAD – CAM SYSTEMS :
• The first cad – cam intraduced was DURET
system by HENNSON .
• CEREC SYSTEM (siemens) this was first fully
operational system developed by BRAINS .
• Its use was limited to inlays , onlays, &veneers.
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80. ADVANTAGES :
• This system enabled dentist to desing and
fabricate ceramic restorations at chair side in a
single appointment .
• DISADVANTAGES :
• This system allowed restoration to be produced
with wide gaps between the tooth and
restoration interface .this gap allows degrade
easily .hence surface seal or bond was lost .
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81. • A newer CAD – CAM system was introduced
by siemens called the CEREC – E or the
ceramic recotouring system with electric
milling machine .this system produces smaller
marginal gaps
• The restoration were bonded using resin cement
that were more resistant to degradation .
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82. • Denti CAD system (Bego) this is the latest
system that comes along with an intraoral
pen digitiger .
• PROCERA system (Biocare) this CAD –
CAM system was use to design crowns by
combining titanium substructure with a low
fusion veneering porcelain .now used to
produce theprocera all ceramic crown .
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83. CEREC SYSTEM
• Cerec system developed in Zurich, Switzerland .
• It is an application –oriented synthesis of 3 –D
imaging ,computer aided design & numerically
controlled machining
• The basic philosophy of the cerac unit is to
combine the scan head for optical impression
with the reconstruction & fabrication module in a
single mobile work station .
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84. CEREC –1 :
• It is an eletrically driven milling machine with
amore efficient cutting disc .
• Accuracy of cut was improved by finer grit &by
increased rigidity of the disc during cutting due
to increased disc thickness .
• It allowed 3-D shaping of the fitting surface of
the restoration against the cavity floor ,
improving the level of fit &allowing a wider
range of shapes to be accommodated .
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85. • The main limitation was not being able to cut
concave surfaces &also extending veneers in to
areas of missing tooth structure proved
problematic .
• Minimal wear of the opposing tooth.
• Due to its strongly translucent nature of ceramic
a light activated composite material as luting
agent .
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88. BENEFITS OF CEREC – 2
SYSTEM
• BENEFITS FOR THE PATIENT :
• Esthetics & cosmetics restoration
• Best material properties in dental ceramics
• Bio compatible
• Cost effective
• Quick turn around time (1 day lab time )
• Perfect occlusion
• High marginal integrity
• No metal in the mouth
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89. BENEFITS FOR THE DENTIST
• Economic production in the laboratory
• Increased precision
• Better inter proximal integrity
• No polishing needed
• Contacts optimized in the laboratory
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90. CEREC – 3 :
• Technique was developed in 1984 .
• Restoration with sound marginal seal
• Used for fabrication of ceramic inlays,onlays
veneers, and quarter,half & complete crowns
for anterior & posterior teeth .
• Technical improvements over CEREC – 3 intra
oral camera , manipulation of the picture &the
grinding unit .
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91. • Proper occlusion is established accurately &
quickly .
• The CEREC – 3 system net work & multimedia
ready and in combination with an intra oral color
video camera (or) digital radiography unit can be
used for patient education &for user training .
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96. OTHER DENTAL CAD/ CAM
METHODS
• HOLODONTOGRAPHY :
• Reported by altschuler in 1971
• Used for tooth prints records with combination
of computer & laser holography .
• serve for diagnostic & forensic purpose
• Applicable to prosthetic &restorative work
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97. • THE DURET / HENNSON / SOPHA system :
• It was introduced in 1985 by Duret a dentist in
• grenoble (France) in cooperation with the French
company HENNSON int .
• It is used for fabrication of crowns
• MICRODENTA SYSTEM :
• The system consist of a 3-D line scanning station &
uses separate operating &machining stations for the
milling of the crowns, copings and bridges,the material
being ceramic & titanium .
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98. CERAMATIC AUTOMATIC COPY – MILLING
SYSTEM :
The system uses cerec vita blocs
In the first step a proinlay is prodused in
patient mouth (or)on a model , which is then
fixed on the scanning side of machine with
scaning 7 machining executed simultaneously
&automaticaly .
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99. • THE CELAY MANUVALLY OPERATED
COPY MILLING SYSTEM :
• Feldspathic ceramic & aluminum oxide is used
in this system
• Inlays, onlays, copings &3-unit bridge
substructures can be milled
• The unit is labor intensive
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100. • THE UNIVERSITY OF SHOWA / NISSAN
CAD / CAM SYSTEM :
• First presented at the tokyo dental show in 1995
• Uses a 4 eye laser spot scanner . Scanningtime
is about 10 mins .
• Titanium &glass ceramic are used as restorative
materials .
• Milling of full crown takes about 1 hr 30 min .
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101. ADVANTAGES OF
CAD/CAM
• Negligible porosity levels in the CAD/CAM
core ceramics .
• The freedom from making impression .
• Reduced assistant time associated with
impression procedures .
• Need for single patient appointment .
• Good patient acceptance .
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102. DIS-ADVANTAGES
• Need for costly equipment
• Lack of computer control processing
support for occlusal adjustments
• Technique sensitive nature of surface
imaging required for prepared teeth.
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103. Procera
• They were produced by noble biocare Goteberg
Sweden and was first described in 1993.
• Original procera system was designed to fabricate
crowns, fixed partial dentures by combining a
titanium substructure with the low fusing
veneering porcelain.
• These all ceramic individual restorations comprise
a densely sintered alumina core.
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104. • A die is first created by a computer controlled
milling process and aluminium oxide powder is
compacted onto the die to form the inner surface of
the coping.
• The outer surface is milled before sintering takes
place. Final creation of anatomic forms and esthetics
is achieved by the buildup of conventional
porcelains.
• Restorations of this system shown to have a precise
fit with marginal openings of less than 70µm and
produces minimal wear of the opposing dentition
provided the material is suitably polished.
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105. PROCERA ALL TITAN
• Its low thermal conductivity, low density,
high strength, biocompatibility make
titanium a desirable restorative material.
• The external contours of the individual
titanium cores for procera all titan bridges
are milled and graphite electrodes create the
fitting surface by a spark erosion process.
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106. • Individual components of the bridges are welded
by laser before the structure is finally veneered
with special porcelain.
• In this way application of CAD-CAM technology,
coupled with traditional spark erosion is set to
enable the production of accurately fitting
titanium-base restoration, while eliminating the
need for costly and technically difficult casting
procedure.
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107. New Shrink Free Ceramics
• The shrink free ceramic is used to form a coping on a
epoxy die by a transfer moulding process. This ceramic
was developed in an attempt to overcome the limitations
of platinum foiled matrices when used beneath
aluminous porcelains i.e. improper fit of crown, firing
shrinkage of porcelain.
• The unfired ceramic is composed of a mixture of
alumina magnesia, alumina silicate and glass frit, wax
and silicone resin plasticizer.
• Some of the alumina reacts with the magnesium oxide to
form magnesium aluminate spinal crystals. This is
accomplished by an increase in volume which of cells
selts sintering shrinkage
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108. Disadvantages:
• Improper marginal fit.
• Leaving a marginal gaps of around 84µm.
• To overcome this double sprue technique
was used firing temperature maintained at
128°C.
• Newer shrink free all ceramic.
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109. Hybrid Ceramics
• These ceramics are latest additions to existing ceramic
restorations.
• Estenia (Kurary Dental) is an esthetic resin based
crown and bridge material that provides the advantages
of ceramics (esthetics and durability) and ease of use of
composite materials.
Uses:
- Jacket crowns.
- Inlays.
- Onlays.
- Bridges. www.indiandentalacademy.com
110. Composition
• This ceramic has a resin matrix I.e. strengthened by
loading 0.02 micron superfine microfiller.
• Filler content 92 wt percent loading that cannot be
accomplished by conventional composite materials.
The prepared tooth surface should allow 1.5-2.0mm
space for material.
• The tooth surface is etched with phosphoric acid.
• Then a saline primer is applied on the teeth and air
blown.
• Mix cementing agent Panavia F (increase fillers) and
remove the excess cement.
• Light cure.
• Apply oxyguard wash.www.indiandentalacademy.com
111. Steps for fabricating estenia restoration:
• On a die - apply opaque primer.
- Apply opaquer and light cure.
- Form a body of restoration
and polymerize by light cure.
Following a complete buildup of restoration, heat
cure then finish and polish. Heat curing at 100-
1100°C for 15 minutes.
Properties:
1.Compressive strength – 613 Mpa.
2.Flexural strength – 202 Mpa.
3.Hardness – 200KHN.
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112. ORMOCERS
• Ormocers an acronym for organically modified
ceramics are a new type of materials which
chemically are methacrylate substituted
alkosilanes.
• That is they are organic copolymers the alkylsilyl
groups of the silane allow the formation of an
inorganic Si-O-Si network by hydrolyses and
condensation polymerization reaction to give
cross-linked structures and their properties may be
modified by filler-particle substitution.
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113. • A material is based on this concept has
recently become available (Definite :
Degussa Dental, Hanau, Germany). The
manufacturers claim low shrinkage, high
abrasion resistance, condensability, timeless
aesthetics biocompatibility and protection
against the caries. No long term clinical trial
results are yet available.
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115. References
• Rosenblum M.A., Schulman A. : A review of All-
Ceramic Restorations. JADA, 128: 1997; 297-307.
• Anusavice K.J. : Recent Developments in Restorative
Dental Ceramics. JADA 124: 1993; 72-84.
• Qualtrough A.J.E. and Piddock V. :Recent advances in
ceramic materials and systems for dental restorations.
Dental Update 1999; 65-72.
• Qualtrough A.J.E. and Piddock V.: Ceramics Update.
J. Dent. Res. 1997; 25(2): 91-95.
• Christensen G.J.: A state of the art in esthetic
restorative dentistry. JADA 128: 1997; 1315-1317.
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116. • Mormann W.H. and Bindl A. : The Cerec 3-A
quantum leap for computer-aided restorations: initial
clinical results. Quintessence Int. 31: 2000; 699-712.
• Seghi R.R., Denry I.L. and Rosensteil S.F. : Relative
fracture toughness and hardness of the new dental
ceramics. J. P.D. 74: 1995; 145-150.
• The dental Clinics of North America. Ceramics, 1985,
29:4.
• Anusavice K.J. : Phillip’s Science of Dental Materials.
11th edition.
• Sikri V.K. : Textbook for operative Dentistry, C.B.S.
Publication and distributors, New Delhi, India.
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