429 Too Many Requests

Testimonial article by Dr. Michael Teitelbaum, DMD, MAGD, FACD

A self-adhesive resin cement that contains MDP and LCSi monomers, allowing it to adhere to virtually every material without the need for a separate primer.

Ready to say goodbye to complicated bonding procedures, Dr. Michael Teitelbaum said hello to simplicity with Kuraray Noritake Dental Inc.‘s PANAVIA™ SA Cement Universal, a versatile cementation solution that simplifies his restorative workflow without sacrificing long-term bond strength. “PANAVIA™ is a name I’ve known and trusted since my prosthodontic program over 30 years ago,” shared Dr. Teitelbaum, who said PANAVIA™ SA Cement Universal allows him to confidently cement restorations because of its long-term reliability.

ALL-IN-ONE CEMENTATION SOLUTION

A self-adhesive resin cement that eliminates the need for a separate primer, PANAVIA™ SA Cement Universal contains a unique LCSi monomer that delivers a strong, durable chemical bond to porcelain, lithium disilicate, and composite resin, while a MDP monomer chemically reacts with zirconia, dentin, and enamel. “When I find myself cementing zirconia, my go-to cement is PANAVIA SA™ Cement Universal because it contains MDP, the magic ingredient that lets it actually bond to zirconia,” Dr. Teitelbaum explained. Thanks to a single-step bonding formula, PANAVIA™ SA Cement Universal is an easy-to-use, all-in-one cementation solution, and the material is available in both automix and handmix options. “One of the nice things about PANAVIA™ SA Cement Universal is if you’re in a hurry, maybe doing multiple units or working alone, you can use the automixing syringe tip and inject it into each crown,” said Dr. Teitelbaum. “Or if you’re naturally fast, like my assistant of over 20 years, you can hand mix the cement and load it directly into the crowns.”

“My go-to cement is PANAVIA™ SA Cement Universal because it contains MDP, the magic ingredient that lets it actually bond to zirconia.”

- Michael Teitelbaum, DMD, MAGD, FACD –

VERSATILE AND EASY TO USE

PANAVIA™ SA Cement Universal adheres to virtually all restorative materials without the need for a separate primer, silane, or etchant, simplifying the cementation workflow for clinicians and saving time for patients. “I have a patient who not only gags but makes more saliva than the Colorado River,” joked Dr. Teitelbaum. “It was nearly impossible [with other cements] to keep No. 31 dry long enough to sandblast, etch, prime, mix cement, load the crown and seat it. PANAVIA™ SA Cement Universal was the only cement I could get to work for him.” After the restoration is placed, any excess cement is easy to clean up after a quick 2 to 5 second light cure. “Once you’ve fully seated the crown, you can wave the curing light over the margins for a couple of seconds to just start the set. The excess material easily pops off while still in the rubbery phase,” said Dr. Teitelbaum. PANAVIA™ SA Cement Universal comes in 3 shades, universal (A2), translucent and white, which Dr. Teitelbaum says are suitable for most situations. “For translucent restorations, like inlays where the margins might be visible, I prefer a translucent or universal shade cement,” he said. “But where I may need to see the cement again someday, like an opaque crown or post, I prefer straight white.” Suitable for crowns, bridges, inlays/onlays, posts, and adhesion bridges, PANAVIA™ SA Cement Universal is a versatile cementation solution for virtually every material.

Dentist:

MICHAEL TEITELBAUM
DMD, MAGD, FACD

Is it possible to reduce the number of different cements used in a dental office? In most cases, it is. Kuraray Noritake Dental Inc. is convinced that one or two resin cement systems are usually enough to cover every indication and every need for general cementation. The selection of products may be different depending on personal preferences and the focus on specific dental treatments.

That is why the company offers three high-quality resin cements, with which it is possible to meet the needs and desires of every dentist and patient. One product is available for those who would like to keep it as simple as possible while taking advantage of the multiple benefits resin cements offer over conventional cements. Another system is designed for those who demand highest possible bond strength and aesthetics. And finally, a light-curing system has been developed as a specialized solution for veneer cementation.

In order to facilitate decision making, this article provides in-depth information on each of the three systems and their specific strengths.

The everyday cement

Keeping cementation simple and efficient is possible by minimizing the number of work steps and components and solving existing challenges. The self-adhesive dual-cure resin cement PANAVIA™ SA Cement Universal has been designed for these purposes. The challenge of removing sticky excess cement is overcome by a formulation that allows for very easy excess clean-up.

Components are reduced as the product incorporates Kuraray Noritake Dental Inc.’s Original MDP Monomer and original silane coupling agent, the LCSi Monomer, for a strong and durable bond. While MDP establishes a strong and long-lasting chemical bond to enamel, dentin, metal and zirconia, LCSi is responsible for bonding to resin composite, porcelain and silica-type ceramics (like lithium disilicate), eliminating the need for separate primers.

This means that a single component is needed, which streamlines the procedure, leading to time savings and a minimized potential for errors. Due to its properties, PANAVIA™ SA Cement Universal is ideal for everyday procedures such as the permanent cementation of crowns and bridges made of zirconia, lithium disilicate, hybrid ceramic or even metal.

The strong and aesthetic allrounder

For those who place importance on achieving the highest possible bond strength and aesthetics, PANAVIA™ V5 is the solution. The reliable dual-cure cementation system consisting of a tooth primer, a cement paste and a ceramic primer produces the highest bond strength and aesthetics from the PANAVIA™ cement range.

Therefore, it is an excellent choice for a whole range of indirect restorations and for post-and-core procedures. As the well-aligned components are always combined and applied in the same way, standardization is supported, leading to predictable outcomes.

The veneer specialist

When fulfilling such demanding tasks as cementing veneers, every dental practitioner needs time. Especially when placing multiple veneers at once for the best aesthetic outcomes, having to race against the setting time is counterproductive. For this reason, Kuraray Noritake Dental Inc. developed PANAVIA™ Veneer LC, a light-curing resin cement system with an extended working time of 200 seconds* on the primer, which allows users to initiate polymerization whenever they are ready for it.

PANAVIA™ Veneer LC also offers a well-aligned paste viscosity and consistency for easy dispensing and seating, and comes in four highly colour-stable shades for long-lasting aesthetics. Finally, the system provides for easy excess removal after tack-curing and an excellent bond strength over time.

** Working time: sensitivity to light (8000 lux, ISO 4049)

Meeting expectations

The three products mentioned are precisely what is needed to cover every personal preference and specific indication. They are based on Kuraray Noritake Dental Inc.’s long-standing expertise in the development of adhesive resin cements. The first product from the PANAVIA™ brand was introduced in the 1980s and since then, the company never stopped improving the portfolio by combining existing technologies like the original MDP Monomer with newly developed ones, such as the LCSi Monomer and the Touch Cure Technology. All this ultimately resulted in the current lean portfolio of easy-to-use and highly aesthetic resin cements that provide top-level bond strength.

The prerequisite for adhesive luting is a reliable bond between the tooth and the restorative material. The quality of the bond depends on the resin cement and its correct application. The state of the bonding surface also plays a decisive role. The surfaces of the tooth and restoration must be conditioned and clean. We spoke with Dr. Adham Elsayed.

All-ceramic restorations require adhesive luting. Is this true for all restorative materials (zirconia, lithium disilicate, hybrid ceramics, etc.)?

Yes and no, several factors must be taken into account. The first important factor are the material properties, especially the flexural strength. Fortunately, clear guidelines based on scientific studies are available. As a guideline, all materials with a flexural strength of less than 350 MPa should be placed with an adhesively luted. Correct adhesive luting stabilizes the restoration and tooth structure. Restorative materials of higher strength (e.g. reinforced glass-ceramics, lithium disilicate ceramics, zirconia, etc.) can be cemented with conventional methods. However, some studies indicate that an adhesive luting can improve the overall stability, whereas others show no significant difference.

Another factor guiding the decision for or against adhesive luting is the preparation design. For crowns and bridges, the decisive factor is whether the operator has been able to adhere to the preparation guidelines (minimum abutment height of 4 mm and maximum convergence of 15 degrees)1-5 in order to create the required retention and resistance form for conventional cementation. Minimally invasive restorations, such as resin-bonded fixed dental prothesis (FDPs), veneers and inlay FDPs, are based on a non-retentive preparation design. In such cases, only adhesive luting can ensure adequate retention.

Aesthetics is another important factor. Besides the restorative material, the luting material also has a major impact on the optical outcome. For highly translucent ceramics in particular, it is recommended to resort to adhesive luting. While conventional cements are usually only available as opaque materials, resin composites come in different colours with higher colour stability (PANAVIA V5 or PANAVIA SA Universal).

How should the surface be pre-treated or conditioned for adhesive luting?

Pre-treatment of the surface depends on the structure or microstructure of the ceramic. Silicate ceramics (e.g. glass ceramics) have a glass phase and can be etched. Etching increases the surface area, thus preparing it for adhesive luting. In contrast, oxide ceramics like zirconia as well as composites have no or neglectable amount of glass phase. They cannot be etched. Their surface is conditioned by air-abrasion (with aluminium oxide). This is the only current method which is scientifically proven for achieving a dependable bond with these materials.

How important is correct cleaning of the tooth and restoration surface for the quality of the bond?

The restoration surface must be decontaminated immediately prior to luting. Contamination must be removed thoroughly. Rinsing with water or alcohol has been shown to be insufficient. Therefore, cleaning solutions such as KATANA Cleaner have been developed.

Rub it in, rinse and dry—that's all—for optimal bonding procedures. Unlike other cleaning products, which have to be rubbed in for longer and are only suitable for extraoral use due to their high pH value, KATANA Cleaner is applied within 10 sec. and is suitable for both intraoral and extraoral use.

Any contamination is detrimental for the adhesive bond. At try-in of the restoration, for example, its surface becomes contaminated. Saliva, possibly blood, etc. accumulate and the proteins contained act to isolate all subsequently applied components (e.g. the primer). Any contamination must therefore be thoroughly removed prior to the bonding procedure. This is also the case for direct adhesive restorations. KATANA Cleaner offers a simple and quick way to accomplish this task.

What makes KATANA Cleaner so interesting for the user?

The special features of KATANA Cleaner are its integrated MDP salt and mild pH-value. Let's look at the function of the MDP salt. Rubbed in (for 10 seconds), the cleaner causes the contaminant particles (e.g. remnants from the work process, proteins from saliva, blood, etc.) to adhere to the MDP salt, like a magnet. The contamination is flushed out of the surface by rinsing with water. This ability is attributable to the MDP salt and makes KATANA Cleaner interesting and easy to use. In addition, the pH-value allows us to use the cleaning solution both intraorally and extra-orally, which is another special feature. We generally recommend the use of KATANA Cleaner—for both direct and indirect restorations. Thanks to the universal applicability of the cleaning solution, only one material is needed, while the time required is extremely low. Even for bonding abutments on a titanium base, cleaning with KATANA Cleaner is recommendable as it provides for an ideal basis (before applying the primer). In this case, contamination (e.g. finger grease, residues of the air abrasive) could also act as an insulator and impair the quality of the bond.

References:

1. Ladha K, Verma M. Conventional and contemporary luting cements: an overview. J Indian Prosthodont Soc. 2010;10(2):79-88.
2. Edelhoff D, Özcan M. To what extent does the longevity of fixed dental prostheses depend on the function of the cement? Working Group 4 materials: cementation. Clin Oral Implants Res. 2007;18 Suppl 3:193-204.
3. Güth JF, Stawarczyk B, Edelhoff D, Liebermann A. Zirconia and its novel compositions: What do clinicians need to know? Quintessence Int. 2019;50(7):512-20.
4. Smith CT, Gary JJ, Conkin JE, Franks HL. Effective taper criterion for the full veneer crown preparation in preclinical prosthodontics. J Prosthodont. 1999;8(3):196-200.
5. Uy JN, Neo JC, Chan SH. The effect of tooth and foundation restoration heights on the load fatigue performance of cast crowns. J Prosthet Dent. 2010;104(5):318-24.

Are you looking for an easy to use solution for your clinical workflows?

In this short video Swiss dentist Dr. Alessandro Devigus shares his experience using dual curing and self-adhesive cement PANAVIA SA Cement Universal.

CLEARFIL MAJESTY™ ES-2 Universal and CLEARFIL™ Universal Bond Quick have helped me create long-lasting and aesthetic composite restorations with little to no sensitivity for my patients.­

- Donald Jetter, DMD –

Despite getting its start in the early 1900s manufacturing semi-synthetic fibers (former company of Kuraray Co., Ltd.), today, Kuraray Noritake Dental Inc. is known to clinicians as a restorative powerhouse—especially to those who have relied on its advanced material science for years to achieve consistently successful restorations. One reason for Kuraray’s success is the company’s introduction of adhesive monomers to dentistry nearly 4 decades ago. Years of careful research ultimately led to the development of the MDP monomer, whose molecular structure yields greater adhesion and a stronger chemical bond to enamel, dentin, metal, and zirconia. It is the foundation of all products in Kuraray’s CLEARFIL™ and PANAVIA™ product lines, and likely what has led teams of clinicians to crown several of these materials as DPS* Best Products.

CLEARFIL™: A STRONG BOND & AESTHETIC FILL

For restorative dentists, building a strong restoration calls for an artful combination of technique and materials. To satisfy the latter, Donald Jetter, DMD, relies on CLEARFIL™ adhesives and composites. “We have been using Kuraray’s CLEARFIL™ composites and bonding materials in our practice for a very long time now,” he shared. “Our dental supply rep first suggested the material to us as a cost-effective alternative to the composite we were previously using, and that she always received positive feedback from other doctors who had tried it. I reluctantly ordered some and have never looked back.”

After using CLEARFIL MAJESTY™ ES-2 in the A2 shade for several years with success, Dr. Jetter was excited to try out CLEARFIL MAJESTY™ ES-2 Universal, a single-shade composite for posterior restorations. It uses Light Diffusion Technology to mirror the way tooth structure distorts light, resulting in a virtually seamless blend between the restoration and surrounding dentition. Additionally, enamel-like translucency allows for easy polishing to a high gloss. “The new universal shade seems just a bit lighter than the A2 shade but works well to match adjacent tooth structure,” said Dr. Jetter. “I tried another universal shade product that came out prior to CLEARFIL MAJESTY™ ES-2 Universal, but I experienced material failure with it, and it did not handle as well as Kuraray’s material.”

CLEARFIL MAJESTY™ ES-2 Universal pairs well with CLEARFIL™ Universal Bond Quick, a single-bottle adhesive that houses both the original MDP monomer and AMIDE-based chemistry, which rapidly permeates dentin and enamel to eliminate waiting time and dramatically reduce water absorption. Together, the two monomers provide a unique Rapid Bond Technology. Dr. Jetter and his team has been using CLEARFIL™ Universal Bond Quick since it first came to market, after successfully using its predecessor, CLEARFIL™ Universal Bond, for many years. “I like these products because they are single-bottle, fluoride-releasing, universal adhesives with low odor that help achieve less postop sensitivity,” he shared. “I would highly recommend CLEARFIL MAJESTY™ ES-2 Universal and CLEARFIL™ Universal Bond Quick to other dentists, as they’ve helped me create long-lasting and aesthetic composite restorations with little to no sensitivity for my patients.”

PANAVIA™ SA Cement Universal: CEMENTATION SIMPLIFIED

Designed to remove both primer and silane from the cementation procedure, PANAVIA™ SA Cement Universal contains not one, but two monomers: the original MDP monomer and the LCSi monomer, which allows for a strong bond to porcelain, lithium disilicate, and composite resin. “In my 12 years of clinical practice, I have tried using a variety of different cements and what I find myself gravitating toward is the versatile powerhouse of Kuraray’s PANAVIA™, which makes sense since Kuraray revolutionized bonding by introducing the MDP monomer to the world,” said Bilyana Tesic, DDS, who practices in Monterey, CA. After using earlier generations of PANAVIA™ cements, which required mixing several bottles together before application, Dr. Tesic was excited when PANAVIA™ SA Cement Universal changed all that. “PANAVIA™ SA Cement Universal simplified this process into a single step delivered via automix dispenser. Voilà! One cement to rule them all.” Dr. Tesic has been using PANAVIA™ SA Cement Universal for the past two years, and what she appreciates most about the material is its versatility. “It is a self-adhesive, radiopaque, dual-cure resin cement that bonds to enamel, dentin, composite, semi-precious and precious metal, porcelain, fiber posts, and zirconia. It’s easy to dispense and even easier to clean up. Fast setting time, no need to refrigerate, and no postop sensitivity. That all adds up to no headache. I recommend it to anyone looking to simplify their cementation protocols without losing any bond strength.”

PANAVIA™ V5: 'V' IS FOR VERSATILITY

The strongest dentin bonding cement that Kuraray has ever developed, PANAVIA™ V5 simplifies cementation of crowns, bridges, inlays, onlays, veneers, and posts and cores. PANAVIA™ V5’s MDP-based Tooth Primer offers high bond strength in the self-cure mode thanks to unique catalyst technology, while a 1-bottle surface treatment applies to all indirect restorations. “I loved being able to cement a metal post-and-core and ceramic crown all at the same time with the same product,” said Dr. J. Jerald Boseman, who took part in the DPS product review of PANAVIA™ V5. He added that the cement was easier to use, had a longer set time, and was less technique-sensitive than similar products. Available in 5 shades–White, Brown, Universal, Clear, and Opaque–with corresponding try-in pastes, PANAVIA™ V5 offers easy removal of excess cement after light-curing. Just one drop creates a durable bond to hydroxyapatite, metals, composites, and zirconia. “So far, the retention has been good with excellent handling properties,” shared J. Michael Heider, DDS, who has also used previous generations of PANAVIA™ products. “I’m glad to see the best characteristics of PANAVIA™ are being improved further.”

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!

- A commemoration of the company’s 10th anniversary -

Kiyoyuki Arikawa

After graduating from Kyushu University Faculty of Agriculture, Mr. Kiyoyuki Arikawa joined Kuraray. He has been involved in the dental materials business since joining the company, and this year marks his 38th anniversary.

Initially, he led the planning and development of products from the head office, and has won Kuraray's Merit Award for three products, including CLEARFIL™ SE Bond. In addition, since 2006, he has managed the dental materials business as General Manager of each subsidiary in Europe and the United States.

After that, he returned to Japan and served as president of Kuraray Noritake Dental from 2014 to 2020. Currently, he has handed over the president to his junior and is working as CTO.

To commemorate the 10th anniversary of Kuraray Noritake Dental Inc., I have been asked to write an article under the above title. Here in this article, I would like to write about my own impressions and some thoughts I had about the development and commercialization of various products I was directly engaged with. I was an employee of Kuraray before it was integrated with Noritake, so things described in this article will mainly be from the period during which I worked in the Dental Materials Division of Kuraray Co., Ltd. I would like to beg the readers' pardon for my failure to describe in detail Noritake Dental Supply’s products, which originated from that company’s brilliant history in the development and manufacture of dental materials.

PANAVIA™ - A PRODUCT DEVELOPED TO BECOME AN OUTSTANDING BRAND IN THE RESIN CEMENT MARKET

In August 1984, I was assigned to Kuraray’s Dental Materials Division. On that day, when I first came to the office, a celebration was being held in commemoration of PANAVIA™ EX, a dental resin cement released the previous year that had just received the President’s Prize. PANAVIA™ EX was launched with thorough preparation, as a genuine adhesive resin cement, after the company had completed the expansion of the CLEARFIL™ lineup (F, FII, Core, SC and Posterior) that it had begun designing in 1978. PANAVIA™ EX's characteristics, which enable the application of adhesive bridge technique (thanks to its strong adhesion to enamel), were particularly acclaimed by many users around the world, making it a smash-hit product.

Parallel with that great success, we focused on discovering the cause of pulpal stimulation, a problem that sometimes occurred when PANAVIA™ was applied to dentine for luting restorations, and we sought measures to prevent this problem. At first, PANAVIA™ was released with a recommendation to condition the dentine with phosphoric acid in order to increase the strength of its bond to the dentine. However, its highly-hydrophobic paste composition seemed to prevent the MDP monomer from delivering a sufficiently strong bond to dentine. In addition, it appears that the phosphoric acid treatment opened the dentinal tubules, leading to the occurrence of pulpal stimulation. We performed fact-finding surveys and held many conferences with university researchers to resolve this problem of pulpal stimulation. Among the temporary measures we made to prevent the occurrence of pulpal stimulation without changing the existing specifications of the product, we decided to recommend against conditioning the dentine with phosphoric acid, at least in Japan. With the health insurance reimbursement system supplying a good tailwind for PANAVIA™, the common understanding sprang up spontaneously in the dental materials market: "Cases requiring strong adhesion, such as adhesion bridges, should be cemented with PANAVIA™ and those which can be treated with general luting should be cemented with glass ionomer cements."

Since then, five improved versions of PANAVIA™ have been put on the market, to sweep the resin cement markets overseas as well as in Japan. The improvements were made mainly for the purposes of increasing the range of crown restorative materials -- for example to include precious metals and ceramics -- that can be treated with this product, and in order to improve handling ease in the clinical setting. Here, I would like to emphasize that what lay behind our endeavor to improve PANAVIA™ was "realizing a reliable general luting material". In pursuit of this goal, we focused on improving the product by causing the resin cement to make a strong bond to dentine through chemical polymerization. I think that those efforts of ours indeed contributed to the evolution of the PANAVIA™ brand.

The efforts we have made since the launch of PANAVIA™ back there in 1983 have now come to fruition as PANAVIA™ V5, PANAVIA™ SA Cement Universal and, most recently, PANAVIA™ Veneer LC, a light-curing veneer cement with an extra-long working time. When we talk about its PANAVIA™, there is no avoiding mentioning the technologies behind those products, in particular, the development of the indispensable catalyst technology that was incorporated into them. Our catalyst technology is an excellent one that can also be applied to other products, and every day at our Niigata Development Department, R&D activities are still being carried out to improve it further.

Owing to our efforts, these days no complaints are ever heard about pulpal stimulation caused by PANAVIA™. On the other hand, in parallel with developments involving PANAVIA™, glass ionomer cements that have also evolved. These are also widely used and strongly supported by many users around the world.

Providing the characteristics glass ionomer users want is one of the directions we have followed, which has continued since the development of PANAVIA™.

LOOKING TOWARD A UNIVERSAL FUTURE

At a glance, this issue is emblematic of our commitment to continuous innovation and improvement. Many of the articles focus on newly introduced or updated products and clearly demonstrate the science-backed reasoning that have guided their development.

A prime example of this approach is newly launched PANAVIA™ Veneer LC cementation system. By combining tried and tested components of our ever-popular and reliable PANAVIA™ V5 system with new nano-spherical filler technology, this specialist solution possesses excellent clinical and aesthetic properties.

In an illuminating article about how resin cement systems can function during the era of digital dentistry, Dr. Tomohiro Takagaki explains the growing demand for a system that is easy to use and performs up to standards of the modern dentistry, utilising PANAVIA™ SA Cement Universal as an example.

Dr. Clarence Tam provided a clinical case regarding the use of CLEARFIL MAJESTY™ ES-2 Universal to create naturally-blended posterior restorations. An interview with Dr. Adham Elsayed further clarifies the advantages of this composite and how it can be used in everyday dental workflows.

A lively discussion with Dr. Karim Nasr sheds new light on what benefits the multi-layered KATANA™ Zirconia Block can bring to single-visit dentistry. And last but not least, Donald Jetter, provides an insightful overview of the influence that the famed MDP monomer continues to have on Kuraray’s CLEARFIL™ and PANAVIA™ product lines nearly four decades after its introduction to the dental market.

Click here to read. Happy reading!

Start Reading: BOND | VOLUME 9 | 08/2022

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Direct restoration procedures simplified

Some companies mainly make use of basic technologies developed by others to improve their products and introduce new ones, while other companies conduct fundamental research and technology development inhouse. Is this difference relevant for someone who uses the resulting products in the dental practice or laboratory on a daily basis? It is – as companies developing everything from scratch usually have a deeper understanding of the products and their production procedures, which makes it easier for them to modify specific features, solve existing problems and respond to market needs. This article describes the impact of several basic technologies developed by Kuraray Noritake Dental Inc. on the workflow of creating direct composite restorations.

Direct restorations – from complex to simple

Adhesive restorative dentistry using high-performance dental adhesives and resin composites is currently one of the most popular way of treating teeth with carious lesions. Nowadays, a single-bottle universal adhesive and one or two shades and opacities of universal composite are usually enough to create beautiful and durable outcomes, provided that the right materials are selected.

This, however, has not always been the case. For a long time, the techniques used to create direct restorations have been quite complex: adhesives were technique-sensitive multi-bottle and multi-step systems with long application times. Composite filling materials, on the other hand, only produced lifelike outcomes when many different shades and opacities were combined in the right way. And even if the complex procedures were carried out correctly, the risk of microleakage, discolouration and eventually secondary caries was comparatively high. Kuraray Noritake Dental Inc. focused on solving these issues quite early, starting with the utilization of the Original MDP Monomer developed in 1981.

Optimizing the bonding performance

The Original MDP Monomer addressed the issue of limited long-term bonding performance of adhesive systems. MDP’s hydrophilic (phosphate) group forms a particularly strong and long-lasting chemical bond with calcium found in hydroxyapatite, the main component of enamel and dentin. The formed MDP-Ca salt provides the basis for a stable, strong and durable hybrid layer. In combination with the resin in the bonding agent a tight seal of the cavity after light-curing is the result. Down to the present day, MDP is an essential component of any adhesive product from Kuraray Noritake Dental Inc., and it is the key component that made CLEARFIL™ SE Bond become the Gold Standard self-etch adhesive system.

However, convinced that dental adhesives should provide for more than just a strong and long-lasting bond, Kuraray Noritake Dental Inc. started to focus on solving another issue: the risk of demineralization and cavitation caused by bacteria remaining in the cavity. Based on its experience in developing other adhesive monomers, Kuraray Noritake Dental Inc. invented the MDPB monomer that has an antibacterial cavity cleansing effect. Different from antibacterial agents that might impair the bond strength of a subsequently applied adhesive, the MDPB monomer kills remaining bacteria without affecting the bonding performance. It is contained in the primer of the two-bottle self-etch adhesive CLEARFIL™ SE Protect and is immobilized by polymerization.

The bactericidal mechanism of MDPB is presumed to be similar to the well-known antibacterial agent CPC (Cetyl pyridinium chloride), which is in many toothpastes and mouth rinses.

While two-bottle self-etch adhesives has already simplified the adhesive procedure, single-bottle universal adhesives go the extra mile. It is a challenge to bring together ingredients distributed in multi step systems in one bottle without compromising the stability of the product. Current technology now makes this possible. To seal the surface as soon as possible after application, the penetration of the monomers into the dental tissue must be fast and efficient. However, the penetration is usually slowed down by monomers that need time to penetrate the tooth structure – especially wet dentin – and sometimes even need to be rubbed into it. That is why Kuraray Noritake Dental Inc. focused on developing the Rapid Bond Technology. It consists of the Original MDP Monomer combined with newly developed hydrophilic crosslinking amide monomers and is integrated in CLEARFIL™ Universal Bond Quick. The hydrophilic amide monomers provide for a rapid, deep and complete penetration of the dentin and form upon curing a densely cross-linked polymer network responsible for a strong and durable bond. Hence, waiting and rubbing times are eliminated and a tight and long-lasting seal of the cavity is established after light-curing.

Due to their hydrophilicity (water-affinity), the amide monomers of the Rapid Bond Technology penetrate dentin very well. After light-curing, the bond exhibits low water sorption and therefore high aging-resistance.

Optimizing direct restoratives

Combining multiple layers, shades and opacities: The use of highly complex layering techniques for the creation of lifelike composite restorations is luckily a thing of the past in many clinical situations. The reason: highly developed resin composites that blend seamlessly with the adjacent tooth structure. To provide for this favourable feature, Kuraray Noritake Dental Inc. has developed its proprietary Light Diffusion Technology (LDT). The technology is incorporated in special pre-polymerized fillers acting like millions of micro-prisms that transmit and refract light and colour from the surrounding tooth structure. Optimized in size, distribution and refractive index in relation to the matrix, the fillers offer unsurpassed natural blending.

The whole CLEARFIL MAJESTY™ composite line-up contains this proprietary filler technology. Its latest product – CLEARFIL MAJESTY™ ES-2 Universal – in which Kuraray Noritake Dental Inc. makes use of next level LDT allows for a single-shade technique with simplified shade selection: it is available in two shades for the anterior and a single shade for the posterior region, but blends in so nicely that it covers virtually every shade of the VITA classical A1-D4 shade guide.

Refracting and transmitting light in the right way for a great optical integration: light diffusion fillers of CLEARFIL MAJESTY™ ES-2 from Kuraray Noritake Dental Inc.

As a great optical appearance is not only dependent on optical integration and undetectable restoration margins, Kuraray Noritake Dental Inc. also developed fillers that provide for the rest – a natural surface gloss and long-term polish retention. The solution integrated in CLEARFIL MAJESTY™ ES Flow with its three levels of flowability is called Submicron Filler Technology, which consists of glossy submicron-sized fillers. These fillers are so small that light reflections show a natural effect even after wear. Kuraray Noritake Dental Inc.’s exceptional silane technology is used to join millions of those submicron fillers and keep them together over time. It allows for high filler loads in the low-viscosity composites and limits water uptake that would otherwise lead to degradation of the cured composite. The perfect balance between the glossy submicron fillers, light diffusion fillers, resin matrix and proprietary silane technology is responsible for a balanced combination of mechanical and optical properties.

Example of a single-shade restoration made of CLEARFIL MAJESTY™ ES-2 Universal.

Conclusion

Adhesive monomers, filler technologies and silane technology providing for a solid combination of fillers, clusters and resin matrix: Kuraray Noritake Dental Inc. clearly is a trusted expert in the field of adhesive restorations. The proprietary technologies developed during the past decades have definitely contributed to a better (long-term) performance of direct restorations, and to reliable and aesthetic outcomes more easily achieved.

- A commemoration of the company’s 10th anniversary -

Kiyoyuki Arikawa

After graduating from Kyushu University Faculty of Agriculture, Mr. Kiyoyuki Arikawa joined Kuraray. He has been involved in the dental materials business since joining the company, and this year marks his 38th anniversary.

Initially, he led the planning and development of products from the head office, and has won Kuraray's Merit Award for three products, including CLEARFILTM SE Bond. In addition, since 2006, he has managed the dental materials business as General Manager of each subsidiary in Europe and the United States.

After that, he returned to Japan and served as president of Kuraray Noritake Dental from 2014 to 2020. Currently, he has handed over the president to his junior and is working as CTO.

In the early 1980s, shortly after Kuraray entered the dental materials market, Noboru Makino, then Director of the Mitsubishi Research Institute, a major think tank in Japan, made a sensational announcement. He said: "The denture industry will overtake the automobile industry with the advent of an aging society." Many companies, including leaders in the chemical industry that were more or less involved with dental materials, paid attention to this announcement and joined the dental materials market in Japan, one after another.

Now that 40 years have passed since Mr. Makino predicted this thriving dental materials business, we notice that the patient's perception of dentures and the structure of the dental materials market have changed dramatically. First, as the population’s average age gets higher, patients no longer simply accept that inevitably they will end up using dentures. They want to use their own teeth, retaining their natural teeth as long as possible. This has led to an increased demand for implants and resin restorations. Furthermore, patients also began demanding more esthetic effects from their dental treatment and the dental materials market shifted its focus to the more esthetic aspects of adhesion-based dentistry and the development of new types of dental materials, such as those used for the fabrication and bonding of all-ceramic restorations. In parallel, with rapid advances in digital technology, it has become possible to fabricate made-to-order restorations using CAD/CAM systems, instead of using the metal casting method. Under these circumstances, new types of materials, such as zirconia suitable for the fabrication of restorations using CAD/CAM systems, were created to meet the esthetic drive-in dentistry.

This sequence of events illustrates that new technologies are fusing with existing market forces to create new markets based on shifting patient needs, suggesting that the winner in the market will be the company that quickly identifies user needs, creates new technologies, and meets those users' needs. In other words, both Kuraray and Noritake have formed new markets as a result of their earnest efforts to address and solve the problems users have presented to them. In fact, after Kuraray Medical merged with Noritake Dental Supply, I concluded that one thing the two companies had in common was the attitude of taking good care of their products’ users. We all understood their manner of use and the circumstances in which they used the products. We were all making all-out efforts to solve users' problems both before and after the marketing of products. Our determination to stand at the users’ sides and resolve any problems they have with our products as quickly and completely as possible seemed to me to differentiate our approaches from others.

The spread of the novel coronavirus, which caused a global pandemic, has drastically changed patients’ values as related to dental treatment. In the U.S., demand for chair-side zirconia blocks increased as a way to reduce the number of clinic visits, and there was a shift to more expensive treatment options, which was also seen during the Lehman Shock. Therefore, the preference for same-day treatment may become a major trend in dental treatment in the future. In addition, there are many other signs of changing patient needs, such as the widespread use of remote treatment and the rise of ethical consumption in support of sustainability.

In order for us to make further progress and continue to grow for another 20 or 30 years, we have to identify user needs correctly and in a timely manner, and continue to retain these same shared values held by Kuraray and Noritake, embodied in the statement: "We are determined to satisfy user needs”. That is, we need to root our ‘DNA’ within the company’s longstanding body of values, and retain our eternal enthusiasm for developing new markets. I think these ‘genes’ will be indispensable to our future growth.