Sometimes prosthetic solutions that once were the state of the art become unacceptable for patients. This patient, for example, came to replace his old metal- ceramic crowns on his lateral incisors.
Fig.1
Provisional resin crowns were fabricated and used as a prototype
Fig.2
An impression of the preparations was taken, and the model was scanned. In the picture you can see the buccal and palatal views of preparation on the master model.
Fig.3
CAD design project from palatal and buccal views after occlusion and virtual check
Fig.4
Also the CAD design thickness was checked, in order to comply with material prescriptions and soft tissue health, while keeping preparations as conservative as possible.
Fig.5
It is very important to replicate a natural morphology, in order to create a correct design also respecting soft tissues.
Fig.6
After sintering and checking the zirconia crowns on the model, it is possible prepare the surface with a fine grain rubber to reduce the margin line off-set and finish surface texture.
Fig.7
Sandblasting was carried out with aluminum oxide 50 micron particles, at 1.5 atm.
Fig.8
The staining technique allows us to increase the chroma and the value effect of the enamel.
Fig.9
In the picture, you can see the final result after baking.
Fig.10
After a couple of staining steps you can improve texture and gloss with a diamond paste or an extra-fine diamond rubber. Polishing perfectly is also important to obtain a non-abrasive surface.
Fig.11
Here you can see the final result after palatal mechanical polishing.
Fig.12
And the amazing result after cementation.
Fig.13
The polarized filter is very useful for an accurate, final color check.
Conclusions
The new generation zirconia materials allow us to accomplish highly aesthetic results in the anterior area by applying a single-layer conservative approach.
Credits
The clinical part of this case was performed by Walter Devoto.
Bibliography
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3. Burgess J, Cakir D. Tooth wear against ceramic. School of Dentistry UAB, 29 Jan 2010
4. Piconi C, Maccauro G. Zirconia as a ceramic biomaterial. Biomaterials. 1999 Jan;20(1):1-25. Review.
5. Garvie RC, Nicholson PS. Structure and thermodynamical properties of partially
