This document discusses various ceramic materials used for CAD/CAM milling systems in dentistry. It describes feldspathic ceramics like Vita Mark I and Mark II that were among the first used for CAD/CAM produced inlays and onlays. Mica-based ceramics like Dicor and leucite-reinforced ceramics were also introduced. More recently, lithium disilicate reinforced ceramics with higher flexural strengths have been used for restorations. Glass infiltrated alumina and zirconia ceramics like InCeram are also discussed. The document also briefly mentions titanium and zirconia blocks used for crown and bridge frameworks.

1. Ceramic used in milling
system

2. CAD/CAM-compatible feldspathic ceramics
• The first CAD/CAM produced inlay was fabricated in 1985 using a ceramic
block comprising fine grain feldspathic ceramic (VitaTM Mark I, Vita
Zahnfabrik, Bad Sackingen, Germany) .
• The clinical performance of these CAD/CAM inlays and onlays was
evaluated in a 10-year prospective study and a success rate of 90.4% was
achieved. However, a much higher breakage rate of up to 36% after 2 years
was also reported

3. • VitaTM Mark II (Vita Zahnfabrik, Bad Sackingen, Germany), introduced
specifically for CEREC (CerecTM 1 – Siemens GmbH, Bensheim, Germany)
in 1991, exhibited better mechanical properties with a reported flexural
strength from about 100 MPa to 160 MPa when glazed
• have excellent aesthetic properties
• recommended for use in fabricating veneers , inlays/onlays and single anterior
and posterior crowns.
• However, the material is not considered to be strong enough for posterior
load bearing areas although, when used in premolar region, the fracture load
was found to be similar to natural teeth

4. CAD/CAM and mica-based ceramics
• The mica minerals are a group of sheet silicate minerals, consisting of varying
complicated formulae of Si, K, Na, Ca, F, O, Fe and Al
• DicorTM (Dentsply, York, USA) is a mica based glass ceramic marketed for both
laboratory ceramming and machining.
• The machinable version DicorTM MGC is industrially produced and has up to 70%
crystalline phase, as compared to the 45% crystalline content of DicorTM which
may explain the reported increased flexural strength to about 229 MPa
• Its machinability is made possible by the presence of tetrasilicic fluormica, K2 Mg5
Si8 O20 F4, crystals which are highly interlocked within the glassy matrix

5. CAD/CAM with leucite-reinforced ceramics
• It was developed for chair-side single unit restorations
• has a flexural strength of about 160 MPa.
• Clinically it is recommended for single tooth restorations and is available in
High Translucency , Low Translucency

6. CAD/CAM milling lithium disilicate reinforced
ceramics
• Lithium disilicate, Li2SiO5, glasses have their flexure strength between 350
MPa and 450 MPa. This is higher than that of leucite-reinforced dental
ceramics
• The material has been recommended for use in fabricating inlays, onlays,
veneers, anterior and posterior crowns and implant supported crowns

7. CAD/CAM and glass infiltrated alumina and
zirconia ceramics
• It is the most translucent material of the group , recommended especially for anterior
crowns.
• CAD/CAM InCeramTM Alumina has been recommendded for single anterior and
posterior crowns.
• CAD/CAM InCeramTM Zirconia is an example of glass infiltrated zirconia (ZrO2)
toughened alumina (ZTA) and has the highest strength of this group of materials
• However, the opacity of zirconia has limited its use to the posterior region as
substructures for crowns or bridges with one pontic .
• The flexural strength of CAD/CAM InCeramTM Zirconia was found to be favourable
for fixed partial denture (FPD) frameworks

8. Titanium block
• Biocompatible
• Translucence
• Light in weight
• High strength
• Low thermal conductivity
• Used for frames of crowns and bridges

9. Zirconia blocks
1. HPC: zirconia free shrinkage
• Biocompatible and high strength
• used for crown and bridge framework (ant &post crown)
2. HIP zirconia:
Indicated for long span , post , bridge
Biocompatible
High flexural strength

10. 3. DC{SHRINLC ZIRCON}
Soft and chalk used for bridge and single crowns
4. CERCON SMART ZIRCONIA
5. ZS COLORED ZIRCONIA
Zircon block that can by coloured by 5 colours of vita system