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vangelis · 07-09-2008, 02:50 AM

In the past few days I did some internet research. This is what I found out:

1. As I understand the radiation values in yittrium stabilized zirconium differ greatly depending the manufacturer, but are usually several hundred times lower than what you get by drinking milk for example. Radiation is not the major problem.
2. Most of Zirconium diokside is Yittrium stabilized. Yittrium is highly toxic (dust must not get in to the lungs). That is a major thread to the technitian, especially those using manual milling such as Zirkonzahn, Girbach, Schick. It can also be a thread to a patient if a bridge will at some later time be cut in the mouth.
3. Alumina is NON-TOXIC, NON-RADIACTIVE and with several hundred times lower Photoelectric potential. All other parameters (Vickers hardness, Weibull modulus, Compressive strength,...) seems to be equal or in some cases greater than Yittrium stabilized zirconium.
4. The only thing that is therefore questionable is flexural strength. On the official web page I saw that full span bridge could be made, I wonder if this is true and to what extend.
TURKOM-CERA� Ceramic Gallery

On this web pages:
http://www.turkom-cera.com/v3/lang/e...st_tc-vita.pdf
Characterization of Glass-infiltrated Alumina-based Ceramics
you can see interesting thing. First link shows results of flexural tests for Turkom-cera and Vita. TC mean value is 535 while Vita is 318. On the second link the values are upside down. I would suggest that there is a good possibility that research on the second link was done this way on purpose or by mistake. You see, there is a warning in the Turkom-Cera manual NOT to delude the Alumina to much as the flexural strength goes down dramatically. Therefore one can delude alumina on purpose or by mistake, we can not know that. However on the other hand, it would be interesting to callculate Weibull modulus based on flexural tests that were done for Turkom-Cera company.

My first impressions? There are several mistakes made by company:
- I got Trial package, manual inside said it is not for sale. The label on 3 jars inside of a trial package says "Not for sale". But I paid 180 EUR
- I also got Mini pack as well (not the small pack! but mini). The price was OK, cca 2550 EUR, it was promo price. But on the box and on the manual in the box it says you get 1 x 35g Alumina (actually you get 2 x 35g) and it says 2 x Crystal hardener (you actually get 4)

It doesn't say there should be a blue Testing liquid, and so there is no testing liquid. But the manual strongly suggests to use it (?!?). Fine, I'll get it separately.

How is it to work with the material... its like a mixture of water, honey and chewing gum. You have to get used to it. I did several crowns yesterday, today I'll try the pontics and in a few days infiltration and some calculations... See ya!

07-09-2008, 02:50 AM	#12 (permalink)
vangelis Junior Member Join Date: Jul 2008 Posts: 9 Gallery: 0 Rating: 0% (0) Rep Power: 0	In the past few days I did some internet research. This is what I found out: 1. As I understand the radiation values in yittrium stabilized zirconium differ greatly depending the manufacturer, but are usually several hundred times lower than what you get by drinking milk for example. Radiation is not the major problem. 2. Most of Zirconium diokside is Yittrium stabilized. Yittrium is highly toxic (dust must not get in to the lungs). That is a major thread to the technitian, especially those using manual milling such as Zirkonzahn, Girbach, Schick. It can also be a thread to a patient if a bridge will at some later time be cut in the mouth. 3. Alumina is NON-TOXIC, NON-RADIACTIVE and with several hundred times lower Photoelectric potential. All other parameters (Vickers hardness, Weibull modulus, Compressive strength,...) seems to be equal or in some cases greater than Yittrium stabilized zirconium. 4. The only thing that is therefore questionable is flexural strength. On the official web page I saw that full span bridge could be made, I wonder if this is true and to what extend. TURKOM-CERA� Ceramic Gallery On this web pages: http://www.turkom-cera.com/v3/lang/e...st_tc-vita.pdf Characterization of Glass-infiltrated Alumina-based Ceramics you can see interesting thing. First link shows results of flexural tests for Turkom-cera and Vita. TC mean value is 535 while Vita is 318. On the second link the values are upside down. I would suggest that there is a good possibility that research on the second link was done this way on purpose or by mistake. You see, there is a warning in the Turkom-Cera manual NOT to delude the Alumina to much as the flexural strength goes down dramatically. Therefore one can delude alumina on purpose or by mistake, we can not know that. However on the other hand, it would be interesting to callculate Weibull modulus based on flexural tests that were done for Turkom-Cera company. My first impressions? There are several mistakes made by company: - I got Trial package, manual inside said it is not for sale. The label on 3 jars inside of a trial package says "Not for sale". But I paid 180 EUR - I also got Mini pack as well (not the small pack! but mini). The price was OK, cca 2550 EUR, it was promo price. But on the box and on the manual in the box it says you get 1 x 35g Alumina (actually you get 2 x 35g) and it says 2 x Crystal hardener (you actually get 4) It doesn't say there should be a blue Testing liquid, and so there is no testing liquid. But the manual strongly suggests to use it (?!?). Fine, I'll get it separately. How is it to work with the material... its like a mixture of water, honey and chewing gum. You have to get used to it. I did several crowns yesterday, today I'll try the pontics and in a few days infiltration and some calculations... See ya! Last edited by vangelis : 07-09-2008 at 02:52 AM.