New zirconia generations tested: Central findings from everyday laboratory work
Master Dental Technician Hans Jürgen Lange (Darmstadt, Germany) has tested the new, highly translucent zirconia blanks VITA YZ ST and VITA YZ XT (VITA Zahnfabrik, Bad Säckingen, Germany). For the two zirconia variants, translucencies of 46 and 50 percent were determined in laboratory tests. Thanks to their particularly high translucency, the new zirconias are particularly suitable for monolithic and vestibular partial veneer reconstructions in the anterior and posterior region. In the following interview, Hans Jürgen Lange reports on his first experiences with these zirconia blanks.
DV: In your experience, what are the indications for the new super and extra-translucent zirconia VITA YZ ST and XT?
Hans Jürgen Lange, MDT: In the posterior region, I am now using VITA YZ ST instead of lithium disilicate monolithically. Although the bond is greater, VITA YZ ST has a more translucent effect, allowing a natural vitality. After minimal cut-back and individualization, VITA YZ XT is my highly esthetic choice for the anterior region. Due to the high translucency, however, the stumps must not show any discoloration here.
DV: How do you rate the light-optical properties of the new VITA zirconias in comparison with zirconia and glass ceramics from other manufacturers?
Hans Jürgen Lange, MDT: The light-optical properties and the play of light are very good in the VITA YZ ST and XT variants and compare favorably to the competition. Compared to the glass ceramics, I like the play of light of the translucent zirconia variants even better.
DV: The new zirconias are offered both as uncolored white and as a pre-dyed shade variant. When do you prefer which variant?
Hans Jürgen Lange, MDT: I prefer the prestained shade discs here. Due to the high shade fidelity, I experience no surprises in the reproduction during my everyday work in the laboratory, and I have a standardized and safe handling procedure for all my employees.
DV: A prerequisite for reliable shade reproduction is the shade fidelity of the materials used. How do you rate the shade fidelity of the color blanks to the VITA classical A1-D4 shade guide?
Hans Jürgen Lange, MDT: The VITA YZ Color blanks I have processed so far show a very high agreement with the dentin shade of the VITA shade standard. VITA YZ restorations have an increasingly brighter and more vivid effect after incision of the tooth stump from the incisal and occlusal direction.
DV: With VITA YZ SOLUTIONS, a complete zirconia package is now available for every indication. What influence does that have on your material assortment?
Hans Jürgen Lange, MDT: Since VITA YZ XT and ST are each available as pre-dyed color blanks in 16 VITA classical shades, I now have the right zirconia for every patient and for every indication, from the single crown to the multi-unit bridge. This means I have a greater variety in stock and can quickly and efficiently implement any case. Because of this, lithium disilicate will be used less and less in the future.
Report 07/18
