How to condition ceramic surfaces prior to their cementation? And what are the parameters guiding the decision for adhesive, self-adhesive or conventional systems? Dr. Gerard Chiche and Prof. Dr. Markus B. Blatz know the answers. In this lecture, they shared exactly the knowledge needed to achieve predictable results.

October 7^th, 2022 marked the 10^th anniversary of the dental divisions of Kuraray and Noritake becoming Kuraray Noritake Dental Inc. For this celebration, ten internationally renowned experts shared their scientific, technical and clinical know-how in the virtual symposium titled “Up to now and from now on: From innovation to simplification”.

We prepared and uploaded the recording of this fifth and final lecture so you can watch it at your convenience.

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.

Is it possible to simplify direct restorative procedures without compromising the outcomes? In many situations, it is – provided that the right materials and techniques are selected. In this lecture Dr. Nicola Scotti and Prof. Lorenzo Breschi focused on the single-shade technique, discussing its capabilities and limitations.

October 7^th, 2022 marked the 10^th anniversary of the dental divisions of Kuraray and Noritake becoming Kuraray Noritake Dental Inc. For this celebration, ten internationally renowned experts shared their scientific, technical and clinical know-how in the virtual symposium titled “Up to now and from now on: From innovation to simplification”.

We prepared and uploaded the recording of this fourth lecture so you can watch it at your convenience.

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.”

How to select the best zirconia for a specific case? In this lecture, popular master ceramists RDT Aki Yoshida and DT Nondas Vlachopoulos presented their success strategies. They focused on the selection of the best suitable type of zirconia and finishing technique depending on the indication and on patient-specific needs.

October 7^th, 2022 marked the 10^th anniversary of the dental divisions of Kuraray and Noritake becoming Kuraray Noritake Dental Inc. For this celebration, ten internationally renowned experts shared their scientific, technical and clinical know-how in the virtual symposium titled “Up to now and from now on: From innovation to simplification”.

We prepared and uploaded the recording of this third lecture so you can watch it at your convenience.

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!

Is it a good idea to start processing translucent zirconia in the dental office? Learn why two experts – Dr. Mike Skramstad and Dr. Sameer Puri said that it may change everyone’s way of practicing dentistry for the better. In their lecture, the two experts described their chairside workflow in detail, including finishing and polishing steps.

October 7^th, 2022 marked the 10^th anniversary of the dental divisions of Kuraray and Noritake becoming Kuraray Noritake Dental Inc. For this celebration, ten internationally renowned experts shared their scientific, technical and clinical know-how in the virtual symposium titled “Up to now and from now on: From innovation to simplification”.

We prepared and uploaded the recording of this second lecture so you can watch it at your convenience.

USING THE NEXT-GENERATION SELF-ADHESIVE CEMENTS

by Dr. Tomohiro Takagaki.

INTRODUCTION

In recent years, the use of CAD/CAM systems for the production of indirect restorations has become increasingly popular. The shortage of young, qualified staff in the field of dental technology in Japan¹) is likely to contribute to a further increase of automated production techniques such as CAD/CAM, which require fewer manual production steps compared to traditional manufacturing techniques. Also globally, the number of restorations fabricated using CAD/CAM systems is rapidly increasing. This leads to an even more widespread use of innovative, tooth-coloured restorative materials such as zirconia, silicate ceramics and resins.

Demand for placing restorations using the principle of adhesion by resin cements is more and more increasing in daily clinical settings. However, it is difficult and complicated to condition the tooth and restoration surfaces using many primers correctly. In addition, the combination of many different components is time-consuming, complex and cost-intensive. Self-adhesive resin cements, which do not require conditioning the surface of teeth or some restorations with primers, have been released recently, and have become popular among dental practitioners. However, there are many reports²) on the dislodgement of resin-based CAD/CAM restorations and full-zirconia crowns that have been placed using self-adhesive cements. Hence, demand is high for a resin cement system that is both simple to use and reliable in performance.

In this document, I explain the fundamental technology of resin cement systems and their range of applications. In addition, I will introduce the method of using a next-generation self-adhesive cement, PANAVIA™ SA Cement Universal (Kuraray Noritake Dental Inc., Fig. 1), as an example.

Minimally invasive preparations, aesthetic high-quality materials, patient-centered approaches: these are the key ingredients needed for successful restorative dentistry. Eleven renowned dental clinicians, technicians and scientists from all around Europe shared their own strategies for success during the IN.DIRECT SYMPOSIUM on Aesthetic Dental Collaboration that took place on November 5, 2022 at Kristallwelten Swarovski in Wattens near Innsbruck, Austria.

Kazumitsu Nakatsuka, Head of the Business Unit Medical at Kuraray Europe GmbH, extended a warm welcome to the 132 professionals in Wattens and more than 1,500 online participants. He introduced the two chairmen of the event, Prof. Nicola Scotti from the University of Turin (Italy) and Prof. Dr. Mathias Kern from the University of Kiel (Germany). They guided through the programme with its eight lectures focusing on different aspects of restorative dentistry.

The speakers of the IN.DIRECT Symposium: MDT Daniele Rondoni, Prof. Lorenzo Breschi, MDT Nondas Vlachopoulos, Dr. Claudia Scholz, Dr. Andrea Schädler, Prof. Nicola Scotti, Prof. Dr. Mathias Kern, Dr. Davide Cortellini, DT Laura Canale and MUDr. Josef Kunkela, Ph.D. Missing: Prof. Dr. Benedikt Spies.

Consider a feather-edge preparation for full-coverage crowns

Whenever a patient is in need of full-coverage crowns, a clinician should consider opting for a feather-edge preparation instead of a chamfer or shoulder preparation. This was the key message of Dr. Davide Cortellini from Riccione (Italy), who held his lecture together with DT Laura Canale from Rimini. According to the speakers, the feather-edge preparation allows for greater preservation of healthy tooth structures, provides for stability and aesthetics of the gingival tissues and is effortlessly captured with an intraoral scanner. The technique is technically challenging in that the restorative material needs to be thinned out considerably at the margin. With its low minimum wall thickness, high edge stability and superior mechanical properties, monolithic zirconia seems to be the best suited material for this approach.

DT. Laura Canale and Dr. Davide Cortellini.

Offer single-retainer resin-bonded bridges as an alternative to implants

When a single tooth is missing in the anterior region, single-retainer resin-bonded bridges made of 3Y-TZP zirconia may be the best-suitable option preferred by a patient. As Prof. Dr. Mathias Kern stressed during his lecture, they are the only immediate treatment option for young patients with incomplete dentoalveolar development, fit into narrow edentulous spaces (< 7 mm) and are feasible in cases with angulated roots or insufficient bone quantity. Moreover, they have the same positive impact on the patient’s quality of life as implants, while they are clinically proven with high survival rates of 95.4 percent after 15 years¹. Even in the canine and posterior area, zirconia-based single-retainer resin-bonded bridges offer promising results. Key to success is a meticulous bonding procedure involving low-pressure air-borne particle abrasion and the use of an adhesive resin cement system containing MDP (e.g., PANAVIA™ V5).

Give preference to monolithic restorations on implants

On implants, monolithic restorations seem to have the edge over veneered ones. The reason was presented by Prof. Dr. Benedikt Spies from the University of Freiburg (Germany): technical complications are less likely to occur. Lithium disilicate is the proven solution for single units, while zirconia (with its higher strength) leads to promising results in multi-unit reconstructions. One of the beneficial properties of zirconia is the fact that a perfectly polished surface will remain smooth even after aging and loading, which is an indicator of antagonist-friendly behaviour.

Save tooth structure by choosing cubic zirconia with a zero or micro cutback

With its favourable aesthetic properties, cubic zirconia allows users to reduce the wall thickness of their restorations for minimally invasive treatments. As revealed by Prof. Nicola Scotti and MDT Daniele Rondoni from Savona (Italy), the plastic-elastic behaviour of cubic zirconia is similar to that of enamel, so that it is ideally suited as a replacement of enamel structures. The decision to opt for a purely monolithic design and individualization with liquid ceramics (CERABIEN™ ZR FC Paste Stain) or a micro cutback with a micro-layering approach is mainly guided by aesthetics. The amount of reduction in the case of a cutback should be age-related according to Daniele Rondoni, with slightly more porcelain added in young than in older patients. In any case, the occlusal contact surface should be in zirconia and very well polished.

MDT Daniele Rondoni, Prof. Nicola Scotti and Prof. Dr. Manfred Kern during the discussion.

Open the doors for incredible aesthetics with synthetic feldspathic porcelain

The use of synthetic feldspathic porcelain (CERABIEN™ ZR) – either applied solely for porcelain layering on refractory dies or on top of zirconia frameworks – allows for a precise imitation of natural teeth with all their individual characteristics. Tips on how to exploit the full potential of aesthetic zirconia and veneering porcelain were given by MDT Nondas Vlachopoulos from Athens (Greece). He showed several clinical case examples to explain his philosophy and approach, which is minimally to non-invasive and put emphasis on respecting the biological structures. Particularly with the aid of the internal stain technique, the speaker is able to precisely reproduce virtually every characteristic optical effect – from enamel cracks to white spots – depending on the patient’s desires.

MDT Nondas Vlachopoulos.

Adhere to the recommended protocols for success in adhesive cementation

Achieving a strong and durable bond of indirect restorations to tooth structure is easier as it might seem according to Prof. Lorenzo Breschi from the University of Bologna (Italy). He recommended the use of universal resin cement (like PANAVIA™ SA Cement Universal) in the self-adhesive mode for crowns with retentive features made of non-etchable materials. Whenever retention is insufficient and a lot of dentin is exposed, an additional adhesive should be applied to the tooth structure – preferably after selective etching of the enamel. As PANAVIA™ SA Cement Universal contains silane (the LCSi monomer) and the MDP monomer, a separate restoration primer is not needed even with silica-based ceramics. However, a pre-treatment of the restoration’s bonding surface is strictly required, the method depending on whether the material is etchable or not. In cases with a subgingival preparation margin when isolation is difficult, the speaker suggested to use a selective adhesive approach with application of an adhesive everywhere but close to the gingival fluids, so that additional bond strength is offered precisely where needed.

Solve complex cases chairside step by step

Single-visit treatments are the reason for many patients to opt for chairside dentistry. In fact, various clinical situations can be solved chairside, and in many of them, zirconia is the material of choice. Dr. Claudia Scholz and Dr. Andrea Schädler from Kiel (Germany) prefer using KATANA™ Zirconia Block for many indications, and even solve complex cases like full mouth rehabilitations step by step in single units. The shared several tricks e.g. on how to realize bridges on implants by milling and placing the abutments first, scanning them like natural tooth abutments and then producing the bridge. Their experience shows that chairside dentistry is stretched to its limits when the aesthetic demands are particularly high, the insertion direction of implant-based restorations is not clear or the size of a restoration is larger than the largest available block.

Dr. Andrea Schädler and Dr. Claudia Scholz.

Select the restorative material carefully to pave the way for a precise fit

The accuracy of milled CAD/CAM restorations is strongly dependent on the material choice. As MUDr. Josef Kunkela, Ph.D. from Jindřichův Hradec (Czech Republic) showed using his own research results, the internal fit, marginal and dimensional stability (particularly important in complex, long-span reconstructions), and the surface quality of restorations vary not only between, but also within the different material classes. Among all tested materials, different types of KATANA™ Zirconia performed best with regard to the size of the cement gap, margin and surface quality and full-arch distortion. The differences between various types of zirconia may be due to differences in the material composition and blank production. Everyone valuing accuracy and quality of dental restorations should be aware of these factors and carefully select the restorative materials to pave the way for optimal outcomes.

MUDr. Josef Kunkela, Ph.D.

Modern approaches to aesthetic dentistry

CAD/CAM dentistry, innovative restorative materials and adhesive technology have clearly smoothened the way for highly aesthetic, minimally invasive restorative treatment approaches. During the IN.DIRECT Symposium, it became clear that there are many different highly successful strategies available, and that it is the task of the restorative team to select the appropriate option based on the clinical situation and the specific needs of the patient. In the end, patient satisfaction and quality of life are the main indicators of a successful restorative therapy.

The lectures will be available soon on demand on our website, in the newsroom section. Keep an eye out for the announcements on social media. Coming soon…

References

1. Kern M. Fifteen-year survival of anterior all-ceramic cantilever resin-bonded fixed dental prostheses. J Dent. 2017 Jan;56:133-135.

- 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™.