Ivoclar Vivadent IPS Empress CAD Chairside - de-en-es-it-ru - Manual (Page 52)

4
Empress CAD –
Product Information
IPS
Material
IPS Empress CAD is used for the fabrication of highly aesthetic, fully
anatomical single-unit restorations by means of the CAD/CAM
technology.
IPS Empress CAD blocks are made of a leucite-reinforced glass-
ceramic which consists of a glass and a crystal phase. Leucite crystals
of few microns evenly grow in a multi-stage process directly from the
amorphous glass phase. During the fabrication of the blocks, the
semi-finished product in powder form is pressed to blocks in a fully
automated procedure, which enables a maximum of homogeneity.
Given the difference in the coefficients of thermal expansion (CTE)
between the glass phase and the crystal phase (leucite), cooling after
sintering produces compressive stress in the glass phase. This
mechanism results in an increase in strength and enables IPS Empress
CAD to achieve a flexural strength of 160 MPa. This type of material
has been successful, as well as proven for almost 20 years. The
milled restorations feature excellent accuracy of fit and a
homogeneous surface. Subsequently, the restorations may be
stained using IPS Empress Universal Stains and/or veneered using
IPS Empress Esthetic Veneer.
CTE (100–400°C) [10 -6 /K] 16.6
CTE (100–500°C) [10 -6 /K] 17.5
Flexural strength (biaxial) [MPa]* 160
Fracture toughness [MPa m 0.5 ] 1.3
Vickers hardness [MPa] 6200
Chemical resistance [µg/cm 2 ]* 25
*according to ISO 6872