Ivoclar Vivadent IPS e.max ZirPress - Manual (Page 36)

e.max
® ZirPress
Cut-Back Technique
IP
S
In the cut-back technique, IPS e.max Ceram Impulse and Incisal materials are applied in the incisal and/or occlusal area
of the reduced IPS e.max ZirPress. The limited application of layering material permits achieving highly esthetic restora-
tions in an efficient manner.
Finishing
It is of critical importance to use the correct grinding instruments for finishing and adjusting high-strength glass-ceramics. If
unsuitable grinding instruments are used, chipping of the edges and local overheating may occur (please observe the
Ivoclar Vivadent Flow Chart ”Recommended grinding tools for PS e.max glass-ceramics2.
Observe the following procedure for finishing IPS e.max ZirPress restorations:
– Even though adjustment by grinding of pressed IPS e.max ZirPress restorations is possible, it should be kept to a
minimum.
– Separate the sprues with a fine diamond disk under permanent water cooling of the cutting area.
– Overheating of the ceramic must be avoided. Low speed and light pressure is recommended.
– Smooth out the attachment points of the sprues.
– Do not ”post-separate” the framework connectors with separating disks. This may result in undesired predetermined
breaking points, which will subsequently compromise the stability of the all-ceramic restoration.
– If a fully anatomical wax-up was pressed, the restoration is now cut back. Cut back the restoration to make room for the
application of the subsequent layers of Incisal and Impulse materials. Make sure that the minimum thicknesses are
maintained even after the cut-back.
– If the reduction was already carried out on the wax-up, the surface requires slight finishing.
– Make sure that the minimum thickness of 0.6 mm for the pressed ceramic is maintained. If this is not the case, shade
deviations may occur.
– To clean the restoration, briefly blast with Al
2
O
3
at 1 bar (15 psi) pressure and clean with the steam jet.
– Some blasting devices may require different pressure settings to accomplish this procedure.
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Separate the sprues with a thin diamond disk and fit the restoration on the model.
Smooth out the attachment points of the sprues using low speed and light pressure and
finish the surfaces. IPS e.max ZirPress restoration with cut-back