Ivoclar Vivadent Zenostar - Manual (Page 5)

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Product information
Material
Zenostar materials are partly sintered zirconia discs stabilized with 3 mol% yttria and designed for use in conjunction with the
CAD/CAM technique. The discs are available in both pre-shaded and non-shaded versions. When sintered to full density, the
material forms a polycrystalline oxide ceramic that consists mainly of a tetragonal zirconium oxide phase as its main constituent (3Y - TZP).
After final sintering, Zenostar demonstrates strength of more than 900 MPa and its fracture toughness exceeds that of glass-
infiltrated ceramics by a factor of more than two. Zenostar can be processed very easily in a suitable CAD/CAM unit in its partly
sintered "chalk-like" state. Milling is carried out with an enlargement of the restoration of approximately 20-25%. Subsequently,
the milled restorations are shrunk to their final dimension in a sintering process. Given the controlled manufacturing process of the
discs, combined with an optimized sintering process in a high temperature furnace from Ivoclar Vivadent or the Wieland Dental
Zenotec range, the shrinkage of the slightly enlarged restorations can be exactly controlled so that excellent accuracy of fit can be
achieved. The zirconia materials attain their final material-specific properties only during the hard sintering process, during which a
structure that is densified to more than 99% forms. This structure features a high fracture resistance and toughness and thus fully
stands up to the clinical challenges presented by the masticatory forces of the posterior region in particular.
Zenostar ideally supplements the range of indications of the IPS e.max materials. For instance, IPS e.max ZirPress can be pressed
onto the high-strength Zenostar frameworks and/or the frameworks can be veneered using IPS e.max Ceram.
CTE (100-500°C) [10 -6 /K] 10.5 ± 0.5
Flexural strength [MPa] 1.) 2.) ≥ 900
Fracture toughness [MPa*m 0,5 ] ≥ 5.0
Chemical solubility [μg/cm²] 1.) <10
Type / Class Type II / Class 6
1.) In accordance with ISO 6872:2008
2.) Typical flexural strength values are:
Zenostar MO 1150 ± 150 MPa, Zenostar T 1200 ± 200 MPa
Micrograph of ZrO
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structure