Interview with DT Giuliano Moustakis

The percentage of restorations made of zirconia in a full-contour (monolithic) design is steadily increasing. As an enabler of this development, companies like Kuraray Noritake Dental Inc. have introduced high-performance zirconia materials with well-balanced optical and mechanical properties along with innovative finishing solutions. A popular example is KATANA™ Zirconia YML with its multi-layered flexural strength, translucency and colour structure. Combined with Esthetic Colorant for KATANA™ Zirconia and CERABIEN™ ZR FC Paste Stain, it is very well suited for a simplified approach to zirconia aesthetics: The Zero-Bake Technique. We had a conversation with DT Giuliano Moustakis about its benefits and areas of application.

Giuliano Moustakis, why is there a need for a new technique related to the finishing of monolithic zirconia restorations?

Like many manufacturers of restorative materials, I truly believe that the trend towards monolithic zirconia restorations is here to stay. The reason is that there is a huge number of patients who place great value on high-quality dental treatments, but have a limited budget. Many of them are interested in metal-free restorations that blend in nicely with the surrounding dentition and are able to withstand the test of time. Reasonable cost is more important to them than highest-end aesthetics. The new materials available on the market allow us to produce restorations with the desired properties, but we need to think about how to combine them in the most effective way to be able to respond to all those demands including the financial one.

Please describe the Zero-Bake Technique.

This technique is based on a monolithic restoration design carried out in the preferred design software. In this step, it is already important to focus on a natural surface morphology – about 80 percent of the morphology are realized in the digital manufacturing procedure. After milling, some morphological details (the last 20 percent) are added with hand instruments. My personal set of instruments consists of two kinds of diamond discs used for the interproximal area of bridges (with virtually no pressure), a round-end straight carbide bur (fine), Panther stones and a zirconia-blade carving instrument. However, any set of instruments that feels comfortable in the hands of its user may be selected for this task. Taking into account the volumetric shrinkage during sintering and the final polishing and glazing, the structure created is ideally slightly over-contoured and clearly defined. It is definitely worth investing time in this preparatory step, as it will make our lives much easier later in the process. After surface texturing, selected colours of Esthetic Colorant for KATANA™ Zirconia – specific dyeing liquids designed for the imitation of natural optical effects – are applied to the surface.

Fig. 1. Working out the details in the interproximal area with rotating disc-shaped instruments.

Fig. 2.  Integration of the micro morphology with a round-end straight carbide bur.

Do you have any recommendations on how to proceed with this set of liquids?

Just follow the colour reproduction of the adjacent natural teeth. With Esthetic Colorant, we want to create beautiful illusions, and nature is our best source of inspiration. To be able to copy what we see, however, we need to understand the properties and behaviour of the materials we use. Consequently, I strongly recommend to test them extensively. For example, you may train on remnants of zirconia blanks before moving on to real patient cases. The duration of the testing period should depend on the outcomes produced, which should be highly predictable at the moment the first patient case is started. I experimented and practiced with Esthetic Colorant for about six months, and did use it on the first real case after one moth of practicing.

Nowadays, there are five effect liquids which I use on a daily basis in almost every case:

• A Plus: Used mainly in the vestibular cervical and palatal cervical and mamelon areas to increase the chroma of A dentin shades
• Blue: Used to reproduced the blueish enamel colour found in the area of the incisal edge and occlusal cusps
• Gray: Used (often in addition to Blue) to reproduce the grayish enamel colour found on the incisal edge and cusps
• Orange: Used to give an orange appearance to the cervical area and to intensify the contours of the mamelons
• Brown: Used to reproduce the dentin colour in the cervical area and to darken the colour in the main groove

In addition, there is a liquid with a special function I value highly: Opaque. This modifier liquid is applied on the intaglio of a restoration to mask discoloured or metal abutments. In order to intensify the effects of this and other liquids, they may be applied to a single spot up to three times.

Fig. 3.  Basic chromatic map for Individualization in the anterior region.

Fig. 4.  Restoration after sintering.

Fig. 5.  Frontal view of a complex restoration including gum parts with information on where to apply which type of Esthetic Colorant.

Fig. 6.  Basal view of the restoration with Opaque applied to mask the screws, and Violet and Pink to add colour to the gums.

Fig. 7.  Occlusal view with colour recommendations.

How do you apply Esthetic Colorant and what are the steps that follow once you have applied them?

For application, I use the dedicated Liquid Brush Pen for Esthetic Colorant. They allow for a controlled application of the desired amount of liquid and thus support predictable outcomes. Once all Esthetic Colorant liquids are applied, it is essential to dry the zirconia at a temperature between 80 and 200° C for a minimum of 30 minutes. During application of the liquids and drying, any contact with metal must be prevented. Therefore, the brushes used during application must be metal-free, and the same holds true for the tray. By adhering to this rule, discolouration is effectively prevented. The subsequently selected sintering protocols are not affected by the effect liquids – and the same for all types of zirconia from the KATANA™ Zirconia Multi-Layered series. Once sintered and cooled down, the surface of the restorations is finished with a set of polishing instruments. My tip in this context is to be careful not to destroy the micro morphology created in the pre-sintering step. To add the final gloss and natural fluorescence, the surface is treated by sandblasting for the application of CERABIEN™ ZR FC Paste Stain, fixed in a single glaze firing procedure.

Does the technique also work without glazing?

Yes, it is definitely possible to do without this step. In this case, however, the restoration will not offer a fluorescent effect. Whenever a restoration is finished without glazing, the surface must be perfectly polished. If completely smooth, the hardness of the material will not cause any harm to the opposing dentition.

What are the main indications for the Zero Bake Technique?

Personally, I use it most often in the context of complex reconstructions and in the posterior region, especially when the available space is limited. It allows for minimal wall thicknesses and the surface is – when well-polished – more antagonist-friendly than a lithium disilicate surface. In other cases, and depending on the financial budget, digitally produced dentin-core crowns are a great option. The dentin core is milled from KATANA™ Zirconia YML, the enamel added using CERABIEN™ ZR Luster Porcelains. Esthetic Colorant, internal stans and CERABIEN™ ZR FC Paste Stain may be added for individual effects. Compared to traditional full porcelain layering, this concept is quicker, involves a lower shrinkage, offers a high stability due to the specific framework design and requires a thinner wall thickness (e.g. 0.6 mm strength of the dentin core plus 0.6 mm porcelain).

Fig. 8.  Example of a dentin-core restoration. The surface morphology is refined with a Panther stone.

Why is it important to develop new design and finishing concepts nowadays?

To my mind, a lack of time is the greatest issue of modern dental technology. Due to a lack of skilled personnel and an expected decrease in the number of dental laboratories in many countries around the globe, we have to keep looking for concepts that help us reduce the time pressure and make our lives easier. While simplifying procedures, however, we need to provide for the same or even a higher quality of the outcomes. This is exactly what I wanted to achieve when starting to develop the Zero-Bake Technique. My personal gain is more free time.

Why do you share your ideas with others by working as an instructor and lecturer?

I simply enjoy interacting with colleagues, equipping them with knowledge and letting them benefit from good ideas.

Dentist:

DT GIULIANO MOUSTAKIS

Giuliano Moustakis has more than 30 years of expertise as dental technician. He was born in Greece but currently resides in Germany, where he has a lab in Falkensee. Giuliano studied at the School of Dental Technology (SBIE) in Athens, Greece. Over the years he completed several other studies in Germany and Japan, including: the maxillofacial prosthetic technician (IASPE), advanced education in functional diagnosis of the temporomandibular joint, Curriculum implant prosthetics for dental technicians (DGZI). He has been a global instructor at Kuraray Noritake Dental Inc. since 2019. Last but not least it is important to note that he is also a gifted and enthusiastic photographer.

Article by Michael Braian DDS, CDT, PHD

Digital advancements revolutionized dentistry, providing efficient, precise dental care¹. Intraoral scanners replace traditional impressions, enabling virtual models for procedures like implant placement, orthodontics, and prosthodontics². Scan bodies aid in digitizing implants, while CAD/CAM improves prosthesis design and fabrication³. Milling and 3D printing offer speed, accuracy, and complexity in creating dental prostheses⁴. These innovations promise a bright future for dental professionals and patients.

The integration of digital technologies in dentistry has brought about significant advancements in dental care1. This case study presents a comprehensive dental rehabilitation of a patient utilizing a digital workflow, including extraction, dentures, implant surgery, intraoral scanning, 3D printed try-ins, and the fabrication of the final monolithic prosthetic construction.

EXTRACTION OF SEVERELY DECAYED TEETH

The first step in the patient‘s dental rehabilitation involved the extraction of severely decayed teeth. This procedure was necessary to eliminate the source of infection and discomfort and to prepare the oral cavity for the subsequent steps in the rehabilitation process. The dentures are later used to simplify the guided surgery planning⁵. Following the extraction, the patient was provided with appropriate postoperative care instructions and a healing period was allowed before proceeding with the next steps (Fig.1).

Fig. 1. Severely decayed teeth prior to extraction.

DENTURES DURING THE HEALING PERIOD

During the healing period of approximately seven months, the patient was fitted with dentures to replace the extracted teeth. This temporary solution allowed the patient to maintain oral function, appearance, and confidence while the extraction sites healed, and the oral tissues prepared for the implant surgery⁶.

IMPLANT SURGERY

In the upper jaw, six implants were placed, while only four were placed in the lower jaw (Fig.2). This decision was based on the patient‘s individual needs and oral anatomy. Studies have shown that the number of implants required for optimal support and stability depends on various factors, including bone quality and quantity, implant position, and prosthesis design⁷. Research suggests that six implants in the upper jaw and four in the lower jaw are sufficient to provide adequate support for a full-arch fixed prosthesis, with high success rates and patient satisfaction reported⁷. Additionally, placing fewer implants can help reduce surgical time and cost, as well as minimize the risk of complications associated with multiple implant placements. Therefore, this approach was deemed appropriate for this particular patient‘s case.

Shortly before KATANA™ Zirconia ML was launched at the IDS in Cologne ten years ago, I had the pleasure to be invited to Japan. We visited the KATANA™ Zirconia production facilities and learned from Kazunobu Yamada and Takuro Nagura how the new material worked. So far, all dental zirconia I had used was white and quite opaque.

I was immediately impressed by the complexity of the production procedure including all the measures taken by Kuraray Noritake Dental to provide for an extremely high material and blank quality. The blanks appeared to have an extremely homogeneous multi-layered structure and a high density responsible for stable edges and smooth surfaces. What we were told in the manufacturing plant was confirmed by Kazunobu Yamada, who shared his experience and showed us several full-contour cases. I was pleasantly surprised by the fact that he was able to produce impressive outcomes without adding any colour. Moreover, Kazunobu Yamada was obviously able to polish the surface of his restorations within seconds. The perfectly smooth surface would allow us avoid the use of glaze, which usually wears off very quickly, leaving a potentially rough surface that may harm the antagonist.

Based on what I had learned in Japan, I went back to Italy and started experimenting with the amazing new material. While Kazunobu Yamada had identified KATANA™ Zirconia ML as the solution for monolithic restorations in the posterior area, I started using it in every region of the mouth – with different design concepts from full-contour to micro-cutback with micro-layering in the vestibular area. The occlusal contact area was always held in plain, polished zirconia.

Fig. 1. Early example of anterior restorations made of KATANA™ Zirconia ML individualized with CERABIEN™ ZR using the new micro-layering technique.

Fig. 2. Possible cutback design.

During the testing period, I learned a lot about the new zirconia, which was so different from earlier generations. The most important insight was that that the processing conditions have a huge impact on the final outcome. Kuraray Noritake Dental provided valuable support e.g. in the form of sintering protocols and processing and finishing recommendations. This helped me develop my own workflow and concept based on a full-contour design in the posterior and different micro-cutback options with micro-layering in the anterior region. For me, this is a perfect combination of the new type of zirconia (KATANA) and the traditional porcelain material (CERABIEN™ ZR Luster Porcelain and Internal Stain).

In May 2013, at a meeting of the Noritake Study Club in Florence, Italy, I presented the new approach for the first time. Many colleagues were enthusiastic about it and started adopting it. While further developments like more translucent (cubic) material variants and a new generation multi-layered zirconia with a flexural strength and translucency gradient increased the application options and aesthetic potential, micro-layering became a truly popular approach used by dental technicians all over the world. In 2016, it was recognized as a relevat workflow during a closed meeting of the European Academy of Aesthetic Dentistry.

Fig. 3. Perfectly polished palatal zirconia surfaces of anterior restorations.

Fig. 4. More recent case showing a patient who received restorations made of KATANA™ Zirconia STML …

Fig. 5. … finished with CERABIEN™ ZR Internal Stains and a micro-layer of CERABIEN™ Luster Porcelain LT1.

But what is the major reason for the success of the concept and of multi-layered zirconia with KATANA™ Zirconia ML as the pioneer? In my opinion, it should not be implemented for greater simplicity or economic reasons, as one might assume at first thought. The time saved in the layering procedure should be spent on other tasks such as surface texturing and a fine-tuning of the processing procedure. The real benefit is that KATANA™ Zirconia ML and its successors allow for better solutions adapted to the patient’s needs. First of all, they enable us to save natural tooth structure, as the required wall thickness is reduced. They also offer mechanical advantages, as chipping is avoided, and the occlusal contact area remains smooth over time. In my dental laboratory, we changed our workflows completely and – preferring a more conservative approach whenever indicated for the case on hand – we often abandon full layering.

KATANA™ Zirconia can be considered as a great contribution to the digital workflow in the dental laboratory and office, which increases the efficiency of prosthodontic procedures. With the KATANA™ Zirconia Multi-Layered series, it is easy to hold our promise of delivering the best possible quality and aesthetics. The reason is that the materials support us in an ideal way, delivering the perfect combination of tradition and innovation.

TIPS AND TRICKS

Case by MDT Daniele Rondoni and MDT Roberto Rossi

Recently, Kuraray Noritake Dental Inc. has introduced Esthetic Colorant for KATANA™ Zirconia – dyeing liquids applied after milling of the company’s multi-layered zirconia. Enthusiastic users of the KATANA™ Zirconia Multi-Layered Series may wonder when and how to use the innovation: In combination with external stains, veneering porcelains or liquid ceramics, or as a replacement of those products? On the monolithic surface or on a dentin structure (framework)? And how much liquid produces the desired effect? Some technical guidance is provided in this article.

The good news: Esthetic Colorant fits perfectly into any existing approach, no matter whether you prefer a full-contour or cutback design. You may apply the liquids solely in a zero-bake technique – just individualize the milled restorations with Esthetic Colorant, fix the colours during the final sintering procedure and polish the surface. On the other end of the spectrum of options is the use underneath different layers of internal stains, porcelains and glaze.

WE UTILIZE ESTHETIC COLORANT MAINLY FOR THREE PURPOSES:

1. To add specific individual characteristics to the restoration, which are not generated by the multi-layered material structure, yet difficult to create with internal stains (examples are a more chromatic body area of a canine in comparison to the adjacent lateral incisor or pronounced mamelon structures). As the liquids diffuse into the structure, a depth effect is created.
   
   Eight liquids are available for the abovementioned purpose: A, B, C and D Plus for changing the brightness and creating shadows, BLUE, GRAY, ORANGE and BROWN for general characterization.

2. To pre-treat tissue areas to produce a perfectly shaded basis for the application of liquid ceramics (CERABIEN™ ZR FC Paste Stain) or Tissue Porcelain.
   
   Two liquids are available for this purpose: PINK AND VIOLET.

3. To prevent a greyish effect caused by the shining through of discoloured abutment teeth or metal parts (posts or implant abutments) – in this case, Esthetic Colorant OPAQUE or WHITE is applied to the intaglio of the restoration. The effect: the incoming light is blocked on the side of the dark element, while the natural translucency in the outer surface area of the restoration is maintained.

PURPOSE 1

An example of how to add specific individual characteristics to the surface of the restoration is the following full-arch case. After sintering, we just added a micro-layer of CERABIEN™ ZR Luster Porcelain and CERABIEN™ ZR FC Paste Stain Clear Glaze.

Fig. 1a. Frontal view of the complex restoration made of KATANA™ Zirconia HTML Plus after milling and the application of different shades of Esthetic Colorant.

Fig. 1b. Occlusal view of the complex restoration after milling and the application of different shades of Esthetic Colorant. Important: Every restoration characterized with Esthetic Colorant should be left to dry for at least 30 minutes prior to sintering.

Fig. 1c. Frontal view of the restoration after the final sintering procedure.

Fig. 1d. Occlusal view of the restoration after sintering.

Fig. 1e. Addition of a micro-layer of CERABIEN™ ZR Luster Porcelain.

FINAL SITUATION

Fig. 1f. Frontal view of the definitive restoration finished with CERABIEN™ ZR FC Paste Stain Clear Glaze.

Fig. 1g. Occlusal view of the final restoration.

Fig. 1h. Great incisal translucency.

PURPOSE 2

The effect of a pre-treatment of the tissue area of a complex restoration is illustrated with the aid of the following example case. Again, we opted for a nearly monolithic design with a minimal cutback in the incisal area of the teeth. The appearance of the originally tooth-coloured tissue area is modified visibly through the application of Esthetic Colorant in the shades PINK and GRAY. Some individual effects are added to the teeth as well.

Fig. 2a. Vestibular view of the milled restoration (material: KATANA™ Zirconia YML).

Fig. 2b. Palatal view of the milled restoration.

Fig. 2c. Vestibular pattern of application of Esthetic Colorant.

Fig. 2d. Palatal pattern of application of Esthetic Colorant.

Fig. 2e. Vestibular view of the restoration after the final sintering procedure.

Fig. 2f. Palatal view of the restoration after the final sintering procedure.

PURPOSE 3

Comparison of restorations on an implant abutment with and without Esthetic Colorant (EC):

HOW TO APPLY ESTHETIC COLORANT?

Essentially, Esthetic Colorant may be applied with any metal-free brush or pen. In our opinion, the best results are obtained by using the Liquid Brush Pen that has been specifically developed for the dyeing liquids. The pen’s housing is filled with the selected shade of Esthetic Colorant and allows for a controlled application, as the tip always dispenses the right amount of liquid and does not dry out. We utilize a separate Liquid Brush Pen for every shade that is frequently in use.

SINTERING PARAMETERS

After drying, which is essential for a good outcome, the restorations treated with Esthetic Colorant may be put into the sintering furnace and sintered according to the schedule recommended for the KATANA™ Zirconia Multi-Layered series. The parameters do not need to be adjusted.

CONCLUSION

The controlled application of Esthetic Colorant is easily accomplished by using the appropriate equipment, while the desired effects are obtained predictably. The liquids’ ease of use, the appropriate number of shades available and the achievable effects are just a few of the many benefits you will find when trying out the new system in your dental laboratory.

Dentists:

THE COMBINATION OF EFFECT LIQUIDS AND MICRO-LAYERING ON HIGHLY AESTHETIC ZIRCONIA IS THE EFFECTIVE WAY TO ACHIEVE OUTSTANDING RESULTS

Case by Leonidas Dimitriou, MDT

As an addition to its well-aligned portfolio of multi-layered zirconia (KATANA™ Zirconia Multi-Layered series) and veneering porcelain for zirconia (CERABIEN™ ZR), Kuraray Noritake Dental Inc. has recently introduced a set of dyeing liquids. Esthetic Colorant for KATANA™ Zirconia is applied to the surface of the monolithic or anatomically reduced zirconia restoration prior to the final sintering procedure. In this way, it is possible to imitate typical internal colour effects of natural teeth quite easily. Depending on the desired outcome, users may add just a final layer of glaze, liquid ceramics or stains and porcelains to their zirconia restorations treated with Esthetic Colorant. The following two case examples are used to demonstrate two different procedures involving the use of the effect liquids.

CASE EXAMPLE 1

In the first case, we produced three two-unit splinted crown restorations for six maxillary anterior teeth. The zirconia crowns (made of KATANA™ Zirconia YML) were anatomically reduced and individualized with Esthetic Colorant mainly in the incisal and cervical areas immediately after milling. For the application of the selected liquids, we used the Liquid Brush Pen specifically developed for Esthetic Colorant. The restorations were dried for half an hour, placed in the sintering furnace for sintering according to the recommended protocol for KATANA™ Zirconia and subsequently finished with CERABIEN™ ZR porcelains. Finally, CERABIEN™ ZR Paste Stain Glaze was applied for the final high-gloss finish.

Fig. 1. Pre-sintered anatomically reduced crowns after milling.

Fig. 2. Esthetic Colorant applied to the milled restorations.

Fig. 3. Appearance of the individualized restorations after the final sintering procedure.

Fig. 4. Restorations after porcelain layering.

FINAL SITUATION

Fig. 5. Final restorations with a natural appearance. The effects created with Esthetic Colorant shine from deep within the restorations.

Fig. 6. Lateral view of the final restorations from the left.

Fig. 7. Lateral view of the final restorations from the right.

CASE EXAMPLE 2

In this second case, two three-unit restorations were produced using KATANA™ Zirconia YML in the colour A3. We designed and milled them in full contour, then reduced them with hand instruments by 0.2 mm and added some texture effects to the surface before applying Esthetic Colorant. In this case, we played with different shades of Esthetic Colorant. Even when applied on a minimally reduced or monolithic surface, the liquids are able to create a nice depth effect as they diffuse into the zirconia structure. The amount of liquid applied is easily controlled with the Liquid Brush Pen, so that the intensity of the colours is predictable. After sintering, we added some internal stains, CERABIEN™ ZR Luster Porcelain and a final layer of CERABIEN™ ZR FC Paste Stain Glaze to finish the restorations. The outcome speaks for itself.

Fig. 8. Milled monolithic restorations with a pronounced surface texture.

Fig. 9. Vestibular and palatal surfaces individualized with Esthetic Colorant to create and intensify some natural colour effects.

Fig. 10. Appearance of the restorations immediately after sintering.

Fig. 11. Restorations after internal staining.

Fig. 12. A layer of luster porcelain applied to the minimally reduced restorations.

FINAL SITUATION

Fig. 13. Final outcome after glazing.

Dentist:

LEONIDAS DIMITRIOU, MDT

Interview with Yoshihisa Yamada
General Manager, Technology Division of Kuraray Noritake Dental Inc.

KATANA™ Zirconia ML was introduced ten years ago, at the IDS 2013 in Cologne, as the dental industry’s first zirconia product with a multi-layered colour structure. Since that event, KATANA™ Zirconia ML blanks have become very popular. Continued development efforts have led to the current line-up of multi-layered materials, KATANA™ Zirconia UTML, STML and HTML PLUS, and our latest product – KATANA™ Zirconia YML. Our new technology with colour, translucency and strength gradation is found in KATANA™ Zirconia YML.

Photo credits to MDT Giuliano Moustakis.

How important was the invention of the Kuraray Noritake Dental’s original multi-layered technology for the dental market?

Our impression is that the material has had a significant impact on the dental market. Being the first zirconia material with a multi-layered colour structure, KATANA™ Zirconia ML was our first product of its class to offer the properties needed for the efficient production of full-contour zirconia restorations with a natural look. Before its introduction, the “full-contour zirconia” concept had not been widely accepted due to the aesthetic properties of the zirconia materials available so far: Many of them lacked the desired level of translucency, while others needed to be treated with dyeing liquids or stains in a complex procedure to obtain a natural shade appearance. With the launch of multi-layered zirconia blanks, which successfully added natural colour gradation to the structure, aesthetic full-contour zirconia restorations started to become popular among dental technicians worldwide. The high potential of the technology was confirmed at the IDS 2013 show, when we saw not only end-users, but also engineers from competing companies come to look at this product.

4-layer colour structure of KATANA™ multi-layered discs.

Photo credits to MDT Daniele Rondoni.

What changes were driven forward by the introduction of KATANA™ Zirconia ML?

After the introduction of KATANA™ Zirconia ML, many companies started developing multi-layered zirconia discs, creating a new dental product category with an added technical and clinical value. We are convinced that the invention of Kuraray Noritake Dental has played a major role in the shift from zirconia exclusively used as a framework material to alternative approaches including full-contour zirconia restorations. If only monochromatic zirconia discs had been available, we imagine that an increased number of dental technicians would have embraced the concept of using liquid colourants to achieve a natural appearance of full-contour crowns and bridges. That would have prevented monolithic zirconia restorations from becoming as popular as they are today.

How did the KATANA™ Zirconia ML technology evolve over the past ten years?

Based on our unique core technology developed for inventing KATANA™ Zirconia ML, we have been continuing making efforts to create even better products. One of Kuraray Noritake Dental’s great strengths is its ability to develop all the raw materials for its zirconia products inhouse. This makes it possible for us to adjust the boundaries between the layers as inconspicuously as possible, even when discs consist of multiple layers. This enabled us to provide multi-layered discs with the required strength and aesthetic qualities, and with a stable, predictable shrinkage rate. In the past ten years, we have focused on adding new materials with different levels of translucency and strength to offer a portfolio that meets the demands of virtually every dental technician, practitioner and patient.

For example, the advent of KATANA™ Zirconia STML, which has even better aesthetic qualities than KATANA™ Zirconia ML, has made it possible to use it all by itself to create highly aesthetic restorations, with no need to characterize or individualize the restorations. Of course, if you use KATANA™ Zirconia Multi-Layered discs and treat the restorations with a surface staining agent, such as CERABIEN™ ZR FC Paste Stain, you can create even more aesthetic restorations in a shorter time.

What are the benefits of Kuraray Noritake Dental’s multi-layered technology, as compared with other manufacturer’s solutions?

KATANA™ Zirconia multi-layered discs offer the advantage of delivering the proper colour even when they are sintered at high speed. There are two reasons for this. First, we developed unique raw materials with suitable characteristics for high-speed firing. This allows the creation of restorations with the same strength, stability, and aesthetics to be achieved after both short- and long-time firing. The second reason is that we possess the technical know-how concerning excellent shading that Noritake Dental Supply, one of Kuraray Noritake Dental’s predecessors, cultivated during its many years spent developing ceramic materials. Noritake Co., Ltd., parent company of Noritake Dental Supply, is a long-established ceramic manufacturer that is famous for its tableware and other outstanding products. It is this background that allows us to properly control pigment coloration using our inorganic pigment know-how and to provide unique firing schedules. These two strengths enable us to bring unique advantages to our products. That is, they remain stable and retain appropriate colouration even under rapid firing schedules.

CERABIEN™ ZR FC Paste Stain being applied to KATANA™ Zirconia restoration.

Photo credits to MDT Roberto Rossi.

How did you manage to shorten the sintering times so significantly, resulting in your speedy sintering with uniform protocols?

When shorter sintering times became possible, Kuraray Noritake Dental recommended that KATANA™ Zirconia ML be sintered for seven hours. After that, when a new furnace claiming being capable of short-time firing was launched, we used it to fire KATANA™ Zirconia ML on a trial basis. We found, happily, that our zirconia material was uniquely compatible with rapid firing. This was the beginning of our full-fledged study of short-time firing of our zirconia material. You could say that we began investigating short-time firing almost by accident. Then, while developing KATANA™ Zirconia STML and KATANA™ Zirconia UTML, successors of KATANA™ Zirconia ML, we focused on incorporating short-time firing into their features and made various adjustments, finally achieving the optimal combination of factors for the successful short-time firing of zirconia.

What are the benefits of Kuraray Noritake Dental’s second-generation multi-layered technology, as compared with other manufacturer’s solutions?

One advantage of KATANA™ Zirconia YML is that it can be applied to treat a wider range of cases without complex limitations on position within the disc. The reason: it delivers this high level of aesthetics while still maintaining great strength. This advantage of being appropriate for a wider range of cases also simplifies inventory management. In addition, users benefit from our expertise in developing raw materials and reproducing colour with ceramics. This expertise enabled us to develop a zirconia product in which each layer has a different level of translucency, while great strength and admirable aesthetics are maintained throughout the whole blank.

The sintering recommendation is only a guideline; some adjustments may be required depending on each individual furnace. If the furnace cannot be set according to the 54- or 90-minute sintering schedule, speed sintering cannot be used.

* The restorations may be removed at 800°C or less depending on the circumstances.
** For the sintering schedule of KATANA™ Zirconia HT, please refer to the Handy Chart in product packaging.

Is it really possible to address every case using only KATANA™ Zirconia YML?

For every case that can be treated either with KATANA™ Zirconia STML, KATANA™ Zirconia UTML, or KATANA™ Zirconia HTML PLUS, KATANA™ Zirconia YML is also an option. Hence, it is possible to use only KATANA™ Zirconia YML for all your zirconia cases – which is probably one of the reasons for its great popularity. It features both great strength and excellent aesthetics, and – being so versatile – it helps simplify inventory management. Of course, Kuraray Noritake Dental’s other multi-layered materials feature outstanding properties as well. Depending on the features you need, it would also be an option to select from these products - KATANA™ Zirconia STML, KATANA™ Zirconia UTML, or KATANA™ Zirconia HTML PLUS – to realize your ideal restorations.

KATANA™ Zirconia YML, finished with CERABIEN™ ZR.

Photo credits to MDT Giuliano Moustakis.

Why is the KATANA™ brand in general so popular among dental technicians around the world?

We think that dental technicians choose KATANA™ because they find that they can create highly aesthetic restorations using simple, straightforward steps.

Is there any further development potential in multi-layered technology?

On the basis of our technical know-how, there is always room for improvement. That is why we never stop innovating and listening to the voice of our customers. Developing what supports them in improving their outcomes while providing for more predictable, less stressful procedures is our ultimate goal. Right now, we expect to develop products with even greater strength, increased translucency, and outstanding aesthetics that will have a natural look resembling real teeth, even when the material used is full-contour zirconia.

Dentist:

YOSHIHISA YAMADA

We are thrilled to share with you our latest brochure – KATANA Zirconia Restoration System, featuring Kuraray Noritake Dental Inc’s product line-up that is dedicated to creating true-to-live restorations.

The KATANA Zirconia Family brochure features a range of lab-side products that are designed to meet the needs of modern dental professionals.

Our zirconia materials offer excellent strength and aesthetics, making them a top choice for prosthetic dentistry. In the new KATANA Zirconia Family brochure, you can read detailed information, key technical parameters, and suggested indication ranges for all our zirconia products - KATANA Zirconia UTML, STML, HTML PLUS, YML and HT. Also, we look at other products from our range such as CERABIEN ZR Porcelain, FC Paste Stain and  Esthetic Colorant that are and excellent choice for characterization of zirconia restorations, provide an overview of the sintering programs of KATANA Zirconia multi-layered discs and offer useful tips and tricks on how to best handle our zirconia.

With the KATANA Zirconia Family brochure, you will have all the basic information you need to make informed decisions about materials suitable for your dental lab.

Have a read, learn more and stay up to date!

According to Koelnmesse, 120,000 visitors from 162 countries attended the 40th International Dental Show between March 14 and 18, 2023. Being one of the 1,788 companies from 60 countries exhibiting at the show, the Kuraray Noritake Dental Inc. team enjoyed being back on-site, and seized every opportunity to connect with end-users of their products in person again. About 60 percent of the visitors and 75 percent of the exhibitors came from abroad. A highly international, euphoric atmosphere and lots of positive feedback on innovations confirmed that the team is on the right track in developing solutions that support users in improving the lives of their patients. However, the visiting dental professionals were not only interested in products for the dental office and laboratory, but also in smart techniques and approaches for their productive use – presented by renowned experts in lectures and hands-on demonstrations.

Laboratory solutions: The professionals were particularly interested in the brand-new Esthetic Colorant and the whole KATANA™ Zirconia Multi-Layered Series.

Hands-on demonstration of MDT Giuliano Moustakis: Zero Bake Technique with Esthetic Colorant and CERABIEN™ ZR FC Paste Stain.

MDT Nondas Vlachopoulos revealing how to obtain aesthetic outcomes with the One-Bake Technique.

Micro-layering with MDT Daniele Rondoni.

A roadmap to white-pink aesthetics shared by MDT Andreas Chatzimpatzakis.

MDT Alek Aronin describing a handcraft approach to highly aesthetic outcomes.

Indirect workflow solutions: PANAVIA™ Cements meeting every need.

Universal Excellence: CLEARFIL MAJESTY™ ES-2 Universal put to a test.

Handling test with direct restorative materials.

Demonstration of the flowable injection technique by Dr Michał Jaczewski.

Dr José Ignacio Zorzin shedding light on how to achieve reliable adhesion with universal products.

CEREC tips and tricks from MUDr Josef Kunkela, PhD.

Looking forward to seeing you at the next International Dental Show in Cologne in 2025 or elsewhere: The Kuraray Noritake Dental team!

Did you know that humans make up to 30,000 decisions every day? Especially in the busy laboratory environment, decisions often have to be made blazingly fast and under time pressure. At least there is one decision we can spare you: Choosing your all-ceramic material! The reason is that we offer you an all-rounder for everyday laboratory use—reliable, safe and with top colour fidelity—KATANA™ Zirconia YML.

The new KATANA™ Zirconia YML is suitable for every indication and delivers uncompromising outcomes. Its special blank structure results from a combination of newly developed raw materials with different yttrium oxide content. This makes KATANA™ Zirconia YML the all-rounder that allows its users to standardize, streamline and simplify their procedures. Save decision-making time and use the time gained for the really pleasant things in everyday laboratory work, like perfect aesthetic finishing, planning or talking to the patient.

KATANA™ Zirconia YML and the path to perfection

Simply beautiful—the KATANA™ Zirconia story is epitomized by enthusiasm for all-ceramics and a passion for aesthetics. Dental technicians' wishes were taken into account, as were the findings of science and materials technology. The state of the raw materials, the purity of the powders, as well as the homogeneity and density of the blanks—the material properties are specifically matched. In conjunction with a meticulously designed in-house manufacturing process, the result is the dependable high material quality for which KATANA™ Zirconia is known and loved.

The success of KATANA™ Zirconia is based on a remarkable feature: Only KATANA™ Zirconia is made using Kuraray Noritake Dental Inc.'s unique, patented raw material technology*. Kuraray Noritake Dental Inc. is one of the few zirconia manufacturers with exclusive access to its own raw material. On this basis, it has succeeded time and again in setting new pioneering trends on the market. The company was the first to launch multi-layered zirconia—its Original Multi-Layered Technology—on the market. Now, with KATANA™ Zirconia YML, a new era in multi-layered zirconia is beginning.

*EP2024300

What makes KATANA™ Zirconia YML so special?

The answer is easy: predictable outcomes. Users benefit from reliable performance, accurate results and easy use. Its high colour fidelity makes the KATANA™ Zirconia Multi-Layered series so distinctive, as does the precision and perfection that zirconia provides. All the masterly competence of dental specialists in one disc! Dental technicians benefit from high cost-effectiveness and productivity. Assured colour fidelity and precision also provide for relaxed working.

New raw material technology

KATANA™ Zirconia YML is based on a new raw material technology derived from decades of zirconia experience. The zirconia imparts translucency as well as flexural strength, together with its proven multilayer colour structure. The special structure results from a combination of new raw materials with different yttrium oxide content. This makes KATANA™ Zirconia YML the ideal all-rounder with which work processes can be standardized, streamlined and simplified.

KATANA™ Zirconia YML combines raw materials with different yttrium oxide content. The result is an all-rounder material with colour, translucency and strength gradation.

More simplicity in the dental lab

The high density and homogeneity of the material provides for excellent marginal quality and edge stability. Seamless multi-layered technology produces a natural appearance with smooth colour and translucency gradients, no transition lines, and more besides. Highly aesthetic results are achieved with minimal effort. Thanks to the high colour stability, dental technicians achieve the desired aesthetics without laborious post-processing. The reliable predictability of the outcomes makes work even more fun.

Monolithic anterior and posterior crowns are half polished and half individualized with CERABIEN™ ZR FC Paste Stain and then glazed. (Images courtesy of DT Enrico Ferrarelli and MDT Daniele Rondoni)

More assurance in the dental lab

The individual layers in the multi-layered blank are optimally matched and shrink homogeneously in the final sintering process. The result is a high level of dependability and optimum quality of results. KATANA™ Zirconia YML is made using Kuraray Noritake Dental Inc.'s patented raw material technology, whereby even the raw material comes from within the company. This represents a clear advantage over most other zirconia manufacturers, as it allows every parameter to be fine-tuned. The variables are optimized for reliable application—down to the smallest detail. This means highly accurate fitting in everyday laboratory work. Retro-adaption or repeated fabrication do not even arise. And if you need to step up the pace: Harmonious material structure and high zirconia competence are prerequisites for optional high-speed sintering too, which is a valuable asset for every dental lab.

More flexibility in the dental lab

High flexural strength in the dentin area, yet high translucency in the enamel area—these features allow KATANA™ Zirconia YML to cover every all-ceramic indication. The zirconia is suitable for producing long-span monolithic bridges as well as thin-walled crowns, cut-back frameworks for micro-layering and even veneer restorations. Due to this versatility, it is possible to replace other ceramic CAD/CAM materials in the laboratory. This makes inventory management so much easier!

The vacation period is over and we all are slowly returning back to our everyday routines and work. With all the travel and holidays in the last months you might have missed this great article in the LabLine Summer edition: Graftless solutions and implant-supported monolithic zirconia fixed prostheses.

It is an extensive, beautiful and detailed case report created and documented by team of well known and respected KOLs: Fortunato Alfonsi, Antonio Barone, Marco Stoppaccioli, Romeggio Stefano and Vincenzo Marchio.

Check it out by clicking here.