Press ceramic, rediscovered

Despite the advent of digital processes, analogue press ceramics remain an economical method of fabricating dental restorations today. With VITA AMBRIA, the new generation of press ceramic, Mr Ömer Gençtürk (Turkey) successfully constructed a cosmetic veneer restoration for four upper incisors of a young patient in combination with veneering ceramic, VITA LUMEX.

Everyone is talking about CAD/CAM, which plays an even greater role in the fabrication of dental restorations. However, analogue press ceramics are still used in many laboratories. It remains an established, economical and efficient fabrication method.

Until now, a reaction layer with the investment material could lead to surface imperfections and fit issues and has been a challenge. The lithium disilicate that is used often appears greyish and lifeless, due to its crystalline structure.

However, that issue is not something practitioners have to settle for, according to dental technician Mr Ömer Gençtürk, owner of Da Vinci Dental Studio in Antalya, Turkey.

He was given the new generation of press ceramic, VITA AMBRIA, made of zirconia-reinforced lithium disilicate for testing, in collaboration with Dr Ahmet Emre Gülerik, a dentist from DentGroup Clinic in Antalya, Turkey.

In combination with veneering ceramic, VITA LUMEX, Mr Gençtürk achieved a highly aesthetic result from the first application and shares his experience in using VITA AMBRIA in fabricating a cosmetic veneer restoration.

Many dental technicians are reluctant to implement new materials in their laboratory. What was your experience with VITA AMBRIA press ceramic?

There are always concerns, especially if processes have generally been working well in the past. In the end, curiosity prevailed. I wanted to see whether I could achieve better results by using the VITA AMBRIA material system.

In fact, I simply followed the instructions for use and there was no learning curve. During the first use, I could see that VITA AMBRIA delivers what it promises. So, there is no need for concern when shifting to this new product.

When working together with the dental practice, how important is absolute shade accuracy of the material to the VITA shade standards?

The VITA shade guides are a standard worldwide. Of course, the material also has to precisely match the corresponding shade tabs. If I determine an A3.5 on the patient, there should also be an A3.5 in the press and veneering ceramic.

This is the only way I can reproduce the shade appropriate for the patient and be confident that my clients are satisfied with my work. VITA AMBRIA, as the shading element, proved to be true to the shade in this patient case.

Removing the mould is always a tense moment. What was your experience with this process?

Removing the mould is the moment of truth because I have never tried VITA AMBRIA before. And, of course, it is also the moment when you hope that the ceramic will come out of the investment material without any damage. The thin veneers in this case study proved to be robust during the removal process.

Another thing I noticed right away was the minimal reaction layer with the investment material and the flawless ceramic surfaces at the right furnace temperature. The restorations came out perfectly.

How did you establish a shade gradient with the veneering ceramic VITA LUMEX AC and reproduce the dentin core?

I managed to use VITA AMBRIA in producing the dentin core in the correct base tooth shade, so I did not have to do much more on the anatomically reduced surfaces to get a three-dimensional result.

For the shade gradient, I layered some OPAQUE DENTINE A1 cervically so it would be less chromatic after the incisal DENTINE A1. I created the mamelon anatomy effect using MAMELON saffron and highlighted it with intermediate layers of a one-to-one mixture of DENTINE A1 and ENAMEL clear.

How exactly did you proceed with the enamel layering using VITA LUMEX AC? What is your advice for creating a halo effect in the process?

I followed with alternating layers of translucent ENAMEL light, neutral ENAMEL clear, light blue OPAL TRANSLUCENT opal-azure and light yellow TRANSLUCENT light-blonde to establish a natural play of colour and light.

After the first firing, the incisal final layering was then carried out with a light blue TRANSLUCENT waterdrop. I was able to achieve a halo effect from the palatal plate using a balanced mixture of OPAQUE DENTINE A1, ENAMEL light and highly fluorescent FLUO INTENSE cream. There you have it: high aesthetics with only two firings.

VITA® and the names of the VITA products mentioned are registered trademarks of VITA Zahnfabrik H. Rauter GmbH & Co.KG, Bad Säckingen, Germany.

Published in Dental Asia July/August issue.