In July 2021, Kuraray Noritake Dental Inc. introduced KATANA™ Zirconia YML (yttria multi-layered). With KATANA™ Zirconia UTML, STML, and HTML PLUS already available, it is the fourth multi-layered zirconia in the company’s portfolio – and for dental technicians striving for simplification and standardization, it is the only zirconia they will need.
Its inner structure is different from the other options in that it features the next generation multi-layer technology with not only colour, but also translucency and flexural strength gradation. This makes KATANA™ Zirconia YML a true all-rounder covering every zirconia indication. While translucency and flexural strength gradation is key property differentiating KATANA™ Zirconia YML from other zirconia options within the KATANA™ Zirconia Multi-Layered Series, there are many factors that differentiate it from other materials in the market. One important point is its perfect adjustment to Kuraray Noritake Dental’s specialized products for polishing, staining, glazing and porcelain veneering. In order to learn more about the differentiating factors, we had a conversation with Antonio Corradi, Scientific Marketing Manager at Kuraray Noritake Dental.
Antonio Corradi, who should consider using KATANA™ Zirconia YML?
Offering strength and translucency exactly where needed in the blank, KATANA™ Zirconia YML is suitable for the whole range of indications from crowns to monolithic long-span bridges. With these properties, it is the perfect choice for anyone who would like to use one single zirconia for the production of any kind of ceramic restoration. Instead of playing with different blanks depending on the indication and patient-specific needs, the increasing fan base of KATANA™ Zirconia YML uses the same zirconia every time, and plays with the position of the restoration in the blank to make it particularly strong or translucent.
KATANA™ Zirconia YML: layers and their translucency and flexural strength values.
What are the finishing options available for users of KATANA™ Zirconia YML within the Kuraray Noritake Dental product portfolio?
Kuraray Noritake Dental offers a well-aligned portfolio of feldspathic ceramics for various finishing techniques. Purely natural aesthetics are obtained by full porcelain layering. The framework is milled from KATANA™ Zirconia YML and afterwards, different layers of CERABIEN™ ZR Shade Base Porcelain, Opacious Body, Body and Enamel Porcelain, Internal Stain and Luster Porcelain are applied and fixed in various bakes. For morphological corrections and final polishing, suitable products from Kuraray Noritake Dental like Noritake Meister Finish Point and Pearl Surface Z are available.
However, a highly aesthetic zirconia like KATANA™ Zirconia YML usually does not require such a complex finishing approach. Instead, a micro cut-back on the vestibular side of the restoration or even a monolithic design with a thin or ultra-thin layer of (liquid) ceramics is sufficient. For the micro-layering approach, we offer a set of CERABIEN™ ZR Internal Stain and Luster Porcelain materials that are usually applied in a two-step procedure. The occlusal and lingual surfaces not covered by porcelain are merely polished e.g. with Pearl Surface Z. For the further simplified ultra-microlayering approach, CERABIEN™ ZR FC Paste Stain is the perfect choice. The liquid ceramic is able to create texture and a 3D effect on the monolithic surface without adding too much volume to call for a reduction of the zirconia.
Purely natural aesthetics are achieved with a complex combination of porcelains.
For highly aesthetic zirconia like KATANA™ Zirconia YML, a simplified micro-layering approach is usually sufficient.
An even more simplified approach is ultra-microlayering on monolithic surfaces with liquid ceramics such as CERABIEN™ ZR FC Paste Stain.
Which of these finishing approaches do you recommend to users of KATANA™ Zirconia YML?
All three approaches are suitable, and I think that ultra-microlayering is often the best option with a highly aesthetic zirconia, when weighing the time and effort involved against the aesthetics of the outcome. However, a dental technician should always take into account the indication-specific requirements and the needs of the patient (e.g. regarding treatment cost, time available and aesthetic demands), as well as the dentist for the selection of the appropriate material combination and finishing approach. A monolithic design finished with ultra-microlayering is definitely worth a try for those who start working with KATANA™ Zirconia YML!
Are there other materials in the Kuraray Noritake Dental portfolio that perfectly match KATANA™ Zirconia YML?
There are many additional products that are perfect for use with KATANA™ Zirconia YML. One such material is KATANA™ Cleaner, which removes saliva or blood from (zirconia) restorations and from prepared tooth structures after try-in. With its high cleaning effect, it is the ideal product for everyone striving for an optimized bond quality and streamlined adhesive procedures. For adhesive bonding carried out in the laboratory or in the dental office, different types of resin cements are offered by Kuraray Noritake Dental. As some dental practitioners might ask for recommendations regarding cement selection and restoration pretreatment, it is worth knowing these products and their range of indications. For KATANA™ Zirconia, we recommend using the self-adhesive resin cement PANAVIA™ SA Cement Universal for restorations with a retentive design and an adhesive cementation procedure with PANAVIA™ V5 for all other types of zirconia restorations.
Resin cement recommendations depending on the indication, preparation design and margin position.
What else differentiates KATANA™ Zirconia YML from similar materials?
Kuraray Noritake Dental is a true expert in the processing of dental zirconia. This profound knowledge has been leveraged to align the different layers within KATANA™ Zirconia YML with their varying yttria concentrations , so that shrinkage ratios and CTE values are harmonized, and a smooth transition from one layer to the next is achieved. This adjustment is only possible as an end-to-end in-house production process has been established, which provides full control over every detail. Unlike other companies purchasing readily mixed powder, Kuraray Noritake Dental uses natural ores to produce the required metal oxides and its own proprietary additive combination for powder production. In addition, an extremely meticulous pressing process is used to minimize the risk of contamination by airborne particles, and specific ingredients are added to increase blank stability. All this leads to high-quality blanks without transition lines and impurities for well-balanced mechanical and optical properties, a high accuracy of fit, a brilliant surface quality and edge stability, and a high design flexibility users will love.
Why do you recommend KATANA™ Zirconia YML to potential users?
To my mind, the new material is definitely worth testing in the own laboratory environment. It offers many properties that have the potential to reduce the inventory and streamline procedures, without compromising the outcomes. Material selection is simplified, sintering may be accelerated, and finishing becomes a lot easier with the proposed techniques and adjusted materials. However, words alone are not enough to reveal the real difference, which can only be sensed when processing the material and creating impressive outcomes.
"Kuraray Noritake Dental is a true expert in the processing of dental zirconia"
Antonio Corradi during the interview.
