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Every tooth has its unique internal shade structure. Esthetic Colorant enables you to easily and efficiently imitate a variety of these unique characteristics.
It is composed of just 12 shades. They facilitate inventory management yet establish that the typical effects - the lifelike colours of natural teeth can be expressed and controlled even before sintering for natural rendering and oral harmony.
Curious how it works? Check out the video to find out!
Are you interested in a specific material and would like to know how it performs? Are you looking for recommendations on how to exploit its full potential? Or would you like to acquire knowledge about new techniques that support the development of your clinical or technical skills?
During the IDS 2023, eight renowned and experienced speakers offer valuable support by sharing their profound practical and theoretical knowledge in lectures and hands-on demonstrations. Every day between Wednesday and Saturday, an exciting, varied programme is offered at the Kuraray Noritake Dental booth in Hall 11.3 (Booth (E010/F019).
Dental practitioners may be particularly interested in a combined lecture and hands-on demonstration given by Dr. Michał Jaczewski and Dr. José Ignacio Zorzin as well as MUDr. Josef Kunkela, Ph.D.
Dr. Michał Jaczewski is a specialist in minimally invasive and digital dentistry with a private practice in Legnica, Poland. His topic: the flowable injection technique, to explore additional possibilities for direct restorations. He will explain when and why to opt for this non-invasive approach, reveal which materials and tools to select and demonstrate how to obtain aesthetic results.
Dr. José Ignacio Zorzin is an Assistant Professor at the Department of Operative Dentistry and Periodontology at the Friedrich-Alexander-University of Erlangen-Nürnberg in Erlangen, Germany. He will present (in German) proven protocols used to achieve reliable adhesion for more complicated cementation cases using universal products such as CLEARFIL™ Universal Bond Quick and PANAVIA™ SA Cement Universal.
MUDr. Josef Kunkela, Ph.D. founded KUNKELA Campus – a uniquely structured training institute for dentists and dental technicians – in 2012 and runs his own research lab in Jindřichův Hradec, Czech Republic. He will elaborate on KATANA™ Properties and CEREC Tips & Tricks in his presentation, to understand the latest zirconia materials and their potential in clinically. Attendees will learn in what way the material choice has an impact on the quality of indirect restorations.
While the aforementioned presentation of MUDr. Josef Kunkela, Ph.D. may be interesting for dental technicians as well, there will be five speakers who focus exclusively on technical approaches.
Giuliano Moustakis, MDT, who currently runs a dental lab in Falkensee, Germany, will reveal how to produce aesthetic monolithic restorations using KATANA™ Zirconia, Esthetic Colorant and instruments for surface texturing. The dyeing liquids creating individual optical effects are applied immediately after milling and fixed during sintering – a Zero Bake Technique! His lecture will be in German.
A time-saving, yet highly aesthetic One-Bake Technique will be demonstrated by Nondas Vlachopoulos, MDT, the owner of AestheticLab in Athens, Greece, while Daniele Rondoni, MDT from Savona in Italy will introduce his approach to micro-layering to the audience – the 4.4.1 Micro-Layering Technique. Depending on the position in the mouth and the age of the patient, the speaker uses different cutback designs and material combinations from internal stains and luster porcelain to liquid ceramics to finish KATANA™ Zirconia Multi-Layered restorations.
A more complex layering approach will be presented by Alek Aronin, MDT, the owner of the Dental Laboratory and Morphology School in Spain. In a lecture and hands-on presentation titled Internal Stains on Refractory with Noritake EX-3, he equips the audience with knowledge on how to imitate nature as closely as possible with the aid of the Internal Stain Technique.
And last but not least, the owner of ACH Dental Laboratory in Athens, Greece – Andreas Chatzimpatzakis, MDT – will elaborate on White-Pink Aesthetics.
To access the complete schedule, please visit our website, www.kuraraynoritake.eu. The website also offers in-depth information about the speakers. For those who are unable to attend a session that attracts their interest, the lectures and hands-on demonstrations will be broadcasted online and will also be available on demand.
Interview with Dr. Karim Nasr
Zirconia is a popular restorative material with highly beneficial mechanical and meanwhile also optical properties. Due to long processing times, especially sintering, the material was initially not suitable for single-visit dentistry. This changed with the availability of zirconia variants with shortened sintering times and special high-speed sintering furnaces.
We discussed with Dr. Karim Nasr, who is senior lecturer at the University of Toulouse in France and head of CAD/CAM postgraduate training, about his actual practice. His passion for CAD/CAM leads him to use CEREC since 2006 (former CEREC trainer) and to found also iAcademy, a training academy about digital dentistry. He shared his experience with us and we talked about his workflow and indication-specific material preferences as well as specific recommendations regarding the use of KATANA™ Zirconia Block in single-visit dentistry.
Dr. Nasr, which chairside CAD/CAM system do you currently use?
Karim Nasr: I am currently using a chairside CEREC Primescan AC system (Dentsply Sirona) combined with a MCXL milling machine (Dentsply Sirona) in my private practice. In my hospital practice and in the specialized esthetic dentistry consultation that I manage, we use a CEREC Primescan AC system combined with a CEREC Primemill milling machine (Dentsply Sirona).
Why did you opt for those components?
Karim Nasr: The choice of this entire system was guided by several criteria. Working on a proprietary chain certainly locks the possibilities of mixing the equipment, but brings real simplicity and fluidity of use. Moreover, the CEREC Software is certainly the most successful CAD software for a chairside use. It offers personalized and easily modifiable restorations in just a few steps. The simultaneous milling of the top (extrados) and bottom (intrados) surfaces without changing the burs ensures a very short milling time. Finally, a large number of materials are available and can be used with this system.
When did you start working with a chairside CAD/CAM system?
Karim Nasr: I discovered and started working with my first chairside system (CEREC 3) in 2005, shortly after graduating. At that time, everything was new in this field. The intraoral scanner, CAD software, milling unit and ceramic materials had just been introduced. All those components allowed us to deliver aesthetic dental treatments within a single treatment session for the first time.
How did the chairside CAD/CAM systems evolve over time?
Karim Nasr: Of course, with the advances in computer technology, the systems have become more efficient. While it was still necessary to powder the surfaces and possible to record one or two teeth in 2005, powder is no longer required in 2022 and complete arches can be scanned in less than two minutes with an accuracy of less than 20 μm. The design process is highly automated and very well assisted – artificial intelligence is used at all stages, making the work easier.
For what purposes do you use your system today?
Karim Nasr: In more than 15 years, the use of my system has evolved a lot. Nowadays, I reserve it for procedures that can be performed in a single session. This is of the greatest utility for my patients and it allows me to optimize my treatment time. For this reason, not only the milling time, but also the time needed for post-processing is crucial for the decision whether to use my chairside CAD/CAM system or to collaborate with a dental laboratory.
What kinds of materials do you process chairside?
Karim Nasr: I think I have tested all the materials available (at least in France), to be able to select the most suitable ones for daily procedures. Currently, I use different kinds of materials depending on the indications encountered: PMMA for temporary restorations, composites for inlays and onlays, glass-ceramics for onlays, overlays and crowns, and finally zirconia for crowns and bridges.
How do chairside CAD/CAM and zirconia go together?
Karim Nasr: In fact, quite simply. For me, a chairside equipment must be able to produce restorations in the same treatment session. Otherwise, it is a labside workflow. Thus, to use zirconia in chairside systems, the milling procedure must be fast and efficient, but above all, the post-processing (especially sintering) process must be fast. For short processing times, dry milling is recommended, as well as the use of a fast-sintering furnace (such as the CEREC SpeedFire from Dentsply Sirona).
What are the benefits of zirconia compared to other ceramic materials?
Karim Nasr: There are many of them. From a biomechanical point of view, the high mechanical strength of zirconia allows us to work with reduced wall thicknesses, which enables us to be more conservative in dental tissues or to choose any placement method (cementation or bonding). From a biological point of view, perfectly polished, zirconia is the most tolerant ceramic, as it is kind to antagonistic teeth and incredibly well tolerated by periodontal tissues. I prefer zirconia for my crowns on implants for this reason.
What was your first impression when you heard about KATANA™ Zirconia Block?
Karim Nasr: I caught a first glimpse of the new material during an event in 2018. KATANA™ Zirconia STML already existed in discs for laboratories and was well known for its aesthetic qualities. Its block version was highly anticipated. But the most amazing feature was the short sintering times announced (with the CEREC SpeedFire in particular). Testing it, I was immediately amazed by the quality of the ceramic and impressed that it is possible to obtain such an aesthetic result (translucency and shade gradation) within such a short time. This is aesthetic zirconia for everyone!
For which indications would you employ KATANA™ Zirconia Block?
Karim Nasr: I reserve the use of KATANA™ Zirconia Block for crowns and for 3-unit bridges. In some cases, I also use it to produce cantilever bridges with a single-retainer design to replace missing incisors (as described by M. Kern). I particularly like it in my cases where I employ a Biologically Oriented Preparation Technique (BOPT) or Vertiprep.
Are there any material features which are particularly interesting for you?
Karim Nasr: Its biomechanical qualities (which are those of zirconia, already mentioned above) already allow me to extend the indications of my chairside restorations. But, in my opinion, the most interesting property is the degree of translucency. Although it is translucent, KATANA™ Zirconia Block is slightly more opaque than glass-ceramics in their lowest degree of translucency. This allows me to use it on discoloured substrates with higher confidence and to avoid the gray effect without having to use an opaque resin cement.
Do you have any recommendations for an ideal processing of KATANA™ Zirconia Block?
Karim Nasr: The use of zirconia in chairside procedures requires certain precautions to be taken in order to achieve the expected results. I have carried out many tests to identify the mistakes not to be made.
First, dry milling is strongly recommended. Nevertheless, it is quite possible to mill in wet environment. However, in this case, it is fundamental to reserve a tank only for the milling of zirconia, never use any lubricant in water (ideally demineralized water), and to have the filters always clean, which means that they need to be cleaned after each milling procedure. After milling, it is important to remove all the powder of zirconia that may have remained on the surface. After dry milling, the restoration must be sprayed with air. The same is the case after the use of burs or polishers to finish the surface. After wet milling, a demineralized water and ultrasound bath may be indicated but is not mandatory.
(Very) fast sintering with CEREC SpeedFire, for example, gives very satisfactory results comparable to conventional slow sintering, which has also been confirmed by scientific literature. Without an appropriate furnace, it is impossible to perform restorations in the same treatment session. However, I do not use CEREC SpeedFire for staining, glazing or micro-layering, but rather a furnace that can be parameterized. Finally, I advise users to finish and glaze only what is necessary (occlusal grooves, vestibular surfaces if visible) and to polish the rest.
Do you have any tips on how to achieve optimal outcomes with KATANA™ Zirconia Block?
Karim Nasr: In anterior cases, I always recommend to perform shading and staining steps in the mouth because there is no better model than the patient himself. Micro-layering in anterior cases makes it possible to improve the aesthetic result with few steps. The 4.4.1. system, which has been specifically developed for KATANA™ Zirconia, makes micro-layering easy to achieve. For polishing, the use of “twist” polishers is recommended. They make it easier to polish all surfaces, especially the occlusal surfaces, both extra-orally and in the mouth. Just like their counterparts for composite, TWIST™ DIA for Zirconia for Zirconia polishers prove to be very effective.
Dr. Nasr, thank you very much.
DR. KARIM NASR
Stratos Chatzichristos just tested the brand-new Esthetic Colorant on restorations made of KATANA™ Zirconia. This is his verdict:
“For me, KATANA™ Zirconia plus Esthetic Colorant is a true killer combination that leaves nothing to be desired. I love to apply the dyeing liquids to my monolithic zirconia restorations to intensify characteristic features and create natural shade effects. Usually, those restorations just need a final layer of glaze to look amazing!”
Would you like to know more about Esthetic Colorant for KATANA Zirconia? Watch this short video explaining the product and highlighting its features and benefits:
Case by Aleksandra Łyżwińska, Warsaw, Poland.
ABSTRACT
Indirect overlays are the contemporary restoration standard for posterior teeth with extensive hard tissue loss. They provide for cuspal coverage, which decreases the likeliness of coronal and/or root fracture. At the same time and in contrast to crowns, overlay preparations minimize the removal of sound tooth structure especially in the cervical region, which is a critical factor.1 Modern dental resin composites allow for direct cuspal coverage in a single-visit appointment. The results of in-vitro studies suggest that these direct overlays are a suitable alternative to their indirect counterparts in specific situations.2-6 The following case report is used to describe the direct restoration procedure by means of a maxillary right molar with an extensive, deep MOD lesion.
INTRODUCTION
In the context of treating a tooth with an extensive carious lesion, a biomechanical risk assessment should be performed. The primary method of reducing the likeliness of tooth fracture is treatment with a restoration that provides cuspal coverage. The contemporary gold standard for biomechanically compromised teeth are adhesively cemented overlays as an alternative to crowns.1 Another option that does not involve labwork is a direct overlay restoration.2-6 The direct approach is especially suitable for long-term temporization, which may be required during orthodontic treatment, for example.
For those who are still hesitant, we have listed several good reasons to come. Those already planning to come should have a look at why it is worth visiting the Kuraray Noritake Dental booth in Hall 11.3 | Stand E010!
Article by Peter Schouten.
I am frequently asked questions about the intraoral repair of porcelain chippings. To achieve success in repairs, it is essential to consider several important issues.
Perhaps the single most crucial issue to recognise is why the chipping occurred in the first place. For example, if loading stress is the leading cause, this should be considered during the repair.
Other issues to consider are removal of contamination, optimal roughening and chemical activation of the surface, and the prevention of contamination during the repair. Also, a rubber dam should be used to isolate the working field.
FUNDAMENTALS OF ADHESION
Adhesive procedures can be only successful by using the proper substances and methods. Different kinds of surfaces often need different treatments for success. However, the three basic fundamentals of adhesion must be respected to achieve the best results.
1) Mechanical retention through a roughened surface.
2) Chemical activation through chemically active substances.
3) High energetic bonding surface allowing for optimal interaction (wetting capacity) between the surface and the applied medium. Contamination will lower the bonding capacities and must be avoided or removed in any case.
TYPES OF FRACTURE
The most frequent fractures are porcelain only and those that include exposure of the substructure in PFZ or PFM prosthesis.
Many cases present with only limited chipping to the porcelain, for example, at the incisal edge. To achieve a durable repair in this instance, start by increasing the bonding/repair area using a fine diamond burr to create a large bevel. A fine grit burr is preferable over a medium or coarse version because a higher number of shallow grooves deliver a more optimal bonding surface than lesser deeper ones do. Additional roughening of the adherent surface by sandblasting with alumina (50 µm grain size, 2 bar pressure) is highly recommended to increase the surface area further.
When repairing porcelain chippings where the substructure is exposed, it is essential to be aware that multiple substrates are dealt with, indicating a need to adjust the repair protocol accordingly.
Clean the roughened fractured surface thoroughly. KATANA™ Cleaner is the product of choice. It is a safe and easy to use product with high cleaning power. It can be used both intra and extra orally on all kinds of dental substrates. After rinsing and thorough drying, the surface is ready for the next step, chemical activation.
CLEARFIL™ CERAMIC PRIMER PLUS contains both silane and MDP and effectively treats both silica-containing ceramics and metal oxides (zirconia) and metals. After application and thorough drying, the composite restoration can be carried out immediately without an extra bonding step. The composite of choice is a durable flowable, CLEARFIL MAJESTY™ ES Flow. It has high flexural strength, even higher than most paste-type composites. Besides that, it adapts to the surface better and easier. Quick and easy polishing and gloss retention are other highly valuated qualities of CLEARFIL MAJESTY™ ES Flow.
HINTS AND TIPS
REPAIR OF PORCELAIN CHIPPINGS VIDEO
Why should you have Esthetic Colorant in your lab?
Esthetic Colorant for “KATANA™ Zirconia” is a set of easy-to-use shading liquids diffusing into the zirconia structure and enabling imitation of variety of internal shade structures.
It is an excellent choice for creating initial characteristics of the restoration before the sintering procedure, and by doing so laying groundwork for the final fast and easy individualization.
Check out the video to learn about the features of Esthetic Colorant and the resulting benefits.
Case by Dr. Yohei Sato, DMD, PhD, Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, JAPAN and Dr. Keisuke Ihara, CDT, i- Dental Lab, JAPAN.
Fig. 1. The patient visited us with a chief complaint of a desire for improved esthetics of the maxillary right and left lateral incisors.
Fig. 2. A core fabricated from a diagnostic wax model was applied and the necessary clearances were determined.
Fig. 3. Since the teeth are microdonts, the preparation of each abutment was completed by simply exposing a fresh surface to be covered by the laminate veneers.
Fig. 4. A layer of porcelain was applied on the lithium disilicate glass substrate, to make a complete laminate veneer.
Fig. 5. After a trial fitting, the inner surface of the laminate veneer was cleaned with KATANA™ Cleaner. The inner surface was conditioned according to the prosthesis‘ IFU.
Fig. 6. Milling. CLEARFIL™ CERAMIC PRIMER PLUS was applied and dried to silane couple the restoration.
Fig. 7. After a trial fitting, KATANA™ Cleaner was applied to the abutment, and rubbed for more than 10 seconds. Then, it was washed off sufficiently (until the cleaner color had completely disappeared), and dried with compressed air.
Fig. 8. K-ETCHANT Syringe was applied and left for 10 seconds before water-washing and compressed air-drying.
Fig. 9. PANAVIA™ V5 Tooth Primer was applied and left for 20 seconds before compressed-air drying.
Fig. 10. PANAVIA™ Veneer LC Paste was applied to the inner surface of the laminate veneer.
Fig. 11. The laminate veneer was seated and the fit checked. Then, the excess cement was tack-cured (not more than 1 second at any one point) and removed. Finally, the restoration was light-cured and finished.
FINAL SITUATION
Fig. 12. This photo shows the laminate veneer restorations one month after placement. The morphology and color of the right and left lateral incisors have been improved, providing a good balance to the entire anterior dentition.
A discoloured abutment tooth, a metal post or tooth-coloured gum areas: It is not always possible to meet the target tooth or gum shade with a pre-shaded zirconia framework. Porcelain layering on a differently coloured base, however, is likely to deliver unexpected outcomes. The “CERABIEN™ ZR” Shade Base line-up has been developed and recently extended by Kuraray Noritake Dental Inc. for those who would like to avoid surprises and provide for a favourable framework colour, right from the start of porcelain layering. The five new opaque shades deliver approximately five times higher opacity than conventional “CERABIEN™ ZR” Shade Base porcelains, and can mask the base colour much more effectively for even more lifelike restorations.
The “CERABIEN™ ZR” Shade Base opaque shade line-up consists of three shades that reproduce tooth colour: Opaque White as a bleaching shade, Opaque Light as an A2 shade, and Opaque Dark as an A3.5 shade. They may be mixed or applied as delivered to the zirconia framework in thin layers to mask severely discoloured or metal areas. In most situations with a severely discoloured base, a precise matching of the target shade is achieved by applying an opaque shade as a first layer and a target-coloured “CERABIEN™ ZR” Shade Base as a second layer.
The other two new opaque shades – “CERABIEN™ ZR” Opaque Light Tissue and Opaque Dark Tissue – are used in a similar way to create a pink-opaque base in the gum areas of tooth-coloured zirconia frameworks (e.g. made of KATANA™ Zirconia Multi-Layered discs), which is perfect for reproducing gingival colour. Applied as a thin coating, the opaque tissue shades neutralise the tooth colour and their moderate reflection improves the colour effect of the subsequently applied tissue porcelains.
With their high masking ability, the new opaque shades make it even easier to adjust zirconia framework colours for highly aesthetic porcelain layering – no matter whether the base colour of a tissue or tooth area needs to be optimized.