Processing of zirconia
Must Zirconia be ground with water cooling (e.g. correction when trying on the frame structure)?
- Water cooling is recommended, but not mandatory.
How does the bonding between ceramic and Zirconia develop?
- Mechanical retention. Compressive stress and surface fusion.
By what means can Zirconia work be cemented?
- Phosphate cement or glass ionomer cement.
Are edge extensions possible after trying-in?
- Edge extensions after trying-in the frame structure are possible by using ceramic shoulders. However it is better to try in the frame-work before milling.
Zirconia frame structures are always friction-free and always fall from the mouth of the patient when trying-in.
- Friction is technically feasible, but not recommended. It would be better to thinly coat the frame structures with Vaseline before trying-in.
The crown edges on Zirconia objects are too thick.
- This is not a material problem, but a processing error. After milling and before sintering the ICE Zirconia blank, the crown edges must be manually and thinly prepared by the technician.
How well does Zirconia fit?
- If the processing is correct, precise fittings in the hundredth range are standard with the Zirkonzahn system. The marginal integrity amounts to 20 μm as with gold work.
What happens when grinding off and/or correction grinding of Zirconia takes place?
- There are no problems, if it is ground off under water cooling and any resulting sharp edges are rounded off.
Is the tangential preparation officially safe enough for Zirconia works?
- There are no objections on the part of Zirkonzahn against tangential preparations when the frame design is appropriate.
Is a Zirconia crown stable enough or possibly unusable after trepanation?
- Using water cooling and with appropriate tools no structural frame damage should occur.
Which drilling tools are recommended for trepanation of Zirconia crowns?
- Zirconia diamond burs are recommended.