Case by MDT Daniele Rondoni

Usually, the aesthetic potential of a dental ceramic material – specifically its translucency – may be increased only at the expense of a decreased flexural strength. The new KATANA™ Zirconia YML from Kuraray Noritake Dental Inc. is different. With its high flexural strength of 1,100 MPa in the lower half of the blank and high translucency in the upper body and incisal areas, it has a high aesthetic potential and an unlimited indication range, as shown using the following case example.

Fig. 1. KATANA™ Zirconia YML 4-unit and 6-unit bridges after milling and sintering. A natural vestibular surface texture plays a decisive role in the creation of aesthetic monolithic restorations.

Fig. 2. The two bridges on the model after ultra-micro layering with CERABIEN™ ZR FC Paste Stain Kuraray Noritake Dental Inc.).

Fig. 3. Stained and glazed restorations and their translucency in transmitted light.

FINAL SITUATION

Fig. 4. Buccal view of the 6-unit bridge cemented in the patient’s mouth.

Fig. 5. Buccal view of the 4-unit bridge cemented in the patient’s mouth.

With this new type of multi-layered zirconia, it is possible to produce aesthetic monolithic restorations suitable even for use in the anterior area. A high design flexibility is offered despite strength gradation, and the high translucency in the incisal area is responsible for a natural look after sintering. Ultra-micro layering and glazing on the monolithic surface will be sufficient to produce outcomes to our patients’ satisfaction.

Dentist:

DANIELE RONDONI, MDT

Born in Savona in 1961 where he lives and has worked in his own laboratory since 1982 with his collaborators. Graduated from the dental technician school IPSIA “P. Gaslini” in Genoa in 1979. He continued his education by attending relevant workshops for the “Italian dental school“ and broadened his professional experience in Switzerland, Germany and Japan. Since 2011 Kuraray Noritake Dental International Instructor.

The fact that different zirconia materials are used depending on the indication is both a blessing and a curse: Blessing because it allows dental technicians to achieve the best possible outcomes in every situation, and curse because the approach requires a extensive inventory and a lot of decisions. For those who prefer to take a more efficient route without compromising the outcomes, KATANA™ Zirconia YML is the new go-to solution. With its strong core and translucent outer layer, this new generation of multi-layered zirconia offers the properties needed for a broad indication range and easily obtained aesthetics.

KATANA™ Zirconia YML is the reinvention of the original multi-layer technology developed by Kuraray Noritake Dental Inc. (Kuraray Noritake Dental) more than a decade ago. It features new raw materials of different yttria concentrations integrated into the well-liked four-layer colour structure. The result is a disc with a well-balanced combination of chroma, translucency and flexural strength gradation.

As all body layers have a flexural strength of at least 1,000 MPa, the new zirconia fulfills the requirements for a broad range of indications even including monolithic long-span restorations. With its proven colour gradient and super-high translucency enamel layer, the aesthetic potiential is so high that it is often sufficient to opt for a monolithic design of the desired restorations and a time-saving finishing procedure such as polishing or ultra-micro layering with liquid ceramics (e.g. CERABIEN™ ZR FC Paste Stain).

The different layers in the blank are perfectly adjusted to each other through an in-house production procedure which ensures easy positioning of the restorations within the blank, a seamless multi-layer structure required for flawless aesthetics, a precise fit and predictable long-term behaviour.

The advanced fabrication and material composition comes with another advantage: A 54-minute high-speed sintering procedure is available for single-tooth restorations and bridges with up to three units. The optical and mechanical properties of the restorations are comparable to those after the alternative 90-minute or seven-hour sintering cycle.

KATANA™ Zirconia YML will be available July 1^st 2021. To celebrate the launch of the new member to our KATANA™ Zirconia family, we invite you to join us for a virtual kick-off symposium on July 3^rd, 2021 at 10:00 CET. We will show you how aesthetic outcomes are achieved with minimal effort, how design flexibility puts you in control and how the pace of procedures is accelerated without compromising quality.

Registration and further information: www.kuraraysymposium.info

Download brochure:

Discover the next step in the evolution of multi-layered zirconia!

Let us introduce you to KATANA™ Zirconia YML, the next step in the evolution of multi-layered zirconia! The material of superlatives will take center stage at the KATANA™ Zirconia YML Virtual Kick-Off Symposium on July 3, 2021. Renowned experts from the scientific and practical field will share important facts and first-hand information on the unique allrounder and its ability to empower dental laboratories.

Celebrating the launch of the new member to our KATANA™ Zirconia family, we will show you how aesthetic outcomes are achieved with minimal effort, how design flexibility puts you in control and how the pace of procedures is accelerated without compromising quality.

Hence, participation is highly recommended for everyone striving for more: more safety, more reliability, more simplicity and, ultimately, more time.

Registration and further information: www.kuraraysymposium.info

Case by Dr. Aleksandra Łyżwińska, DMD

The maxillary left first molar had a Class I cavity on the occlusal surface restored with resin composite many years ago. The restoration needed to be replaced due to severe signs of wear and discolouration, as well as, the occurrence of secondary caries. After removal of the existing restoration and caries excavation, CLEARFIL™ SE BOND 2 was applied to the cavity to establish a stong and long-lasting chemical adhesion to the available enamel and dentin. Containing the original MDP monomer, the bonding agent is able to fulfill this task reliably. Subequently, the bottom of the cavity was filled with CLEARFIL MAJESTY™ ES Flow - Super Low A2, which shows an excellent marginal adaptation and provides for an even surface. The occlusal surface was built up with CLEARFIL MAJESTY™ ES-2 Classic A2 that blends in very well with the adjacent tooth structure, and characterized with some tints for an even more natural appearance.

Fig. 1. Initial intraoral photograph showing the defective restoration on the maxillary first molar after isolation with rubber dam.

Fig. 2. Occluso-lingual view of the initial situation revealing the wear effect.

Fig. 3. Tooth cavity with a matte surface after cavity preparation.

Fig. 4. Glossy cavity surface after application of CLEARFIL™ SE BOND 2.

Fig. 5. Appearance of the molar immediately after placement of a bottom layer of CLEARFIL MAJESTY™ ES Flow - Super Low A2 and modelling of the occlusal surface anatomy with CLEARFIL MAJESTY™ ES-2 Classic A2.

Fig. 6. Linguo-occlusal view of the situation.

Fig. 7. Appearance of the molar …

Fig. 8. … after the application of some tints.

Fig. 9. Result of the finishing …

Fig. 10. … and polishing procedure.

FINAL SITUATION

Fig. 11. Aesthetic treatment outcome after rubber dam removal …

Fig. 12. … and checking of the occlusal contact points.

Dentist:

DR. ALEKSANDRA ŁYŻWIŃSKA
Warsaw, Poland

Dr. Aleksandra Łyżwińska, DMD, is a passionate aesthetic and adhesive dentist. Driven by Evidence Based Dentistry, her goal includes using modern composite materials and bonding agents in her clinical practise. In addition to her primary job, she worked as a lecturer and an assistant professor at the Department of Conservative Dentistry and Endodontics of Medical University of Warsaw, her alma mater.

Case by Dr. Michael Morgan, DDS

Small to moderate-sized posterior restorations are the bread-and-butter of every dental practice. In a procedure that is carried out so frequently, it is particularly useful to work with a restorative material that handles well and has excellent optical properties that blend in a variety of clinical situations – like CLEARFIL MAJESTY™ ES-2 Universal. The product is available in a single universal shade for the posterior region, which enables users to increase their efficiency and eliminates the need for shade determination or laborious multi-shade layering.

When used with CLEARFIL™ SE Protect adhesive and CLEARFIL MAJESTY™ ES Flow, the innovative universal restorative allows me to confidently restore 70 to 80 percent of my simple posterior composite restorations. It handles extremely well, being slightly soft but not sticky, which allows quick shaping and anatomy formation. The procedure is fast and simple, and it leads to natural outcomes, as shown using the following case example. Anyone who has tested CLEARFIL MAJESTY™ ES-2 Universal in the clinical environment will most likely agree that the material is an easy-to-use workhorse every dentist should have in their composite toolbox.

Fig. 1 Initial clinical situation. Second premolar with a composite restoration and first molar with an amalgam restoration in need of replacement.

Fig. 2 Immediate post-operative image.

Fig. 3 Image taken one week after the treatment showing rehydrated tissues and a smooth optical integration of the direct restorations.

Dentist:

DR. MICHAEL MORGAN, DDS

Case by Dr. Aleksandra Łyżwińska, DMD

One tooth. Two appointments. Two lesions appeared in the upper right second premolar of this 17-year-old patient. We decided to restore the mesial lesions first. Caries was excavated and, due to pulp exposure, direct pulp capping performed with mineral trioxide aggregate (MTA). Chemical adhesion to dentin and the biomaterial was established with the 10-MDP-containing universal adhesive CLEARFIL™ Universal Bond Quick, used in the self-etch mode. One benefit of this material is related to the fact that no extensive rubbing onto the surface is required. Blue composite was placed to mark the region of the exposed pulp, and CLEARFIL MAJESTY™ ES Flow - Super Low A2 was applied to the bottom of the cavity. Due to its high flexural strength, this material is a perfect dentin replacement. The rest of the tooth was restored with temporization material. To fill up the core, bulk-fill flowable composite OliBulk MD was used.

For the second appointment, the temporary was removed and caries was excavated in the distal area of the tooth as well. Following cavity preparation, CLEARFIL™ SE BOND 2 was applied to obtain a strong bond to the remaining composite material and the tooth structure. Both cavities were restored with a combination of CLEARFIL MAJESTY™ ES Flow - Super Low A2 and CLEARFIL MAJESTY™ ES-2 Classic A2.

Fig. 1. Intraoral photograph of the initial situation after isolation with rubber dam.

Fig. 2. Situation after cavity preparation and pulp exposure.

Fig. 3. Mineral trioxide aggregate (MTA) applied to cover and protect the exposed pulp tissue.

Fig. 4. Marking of the exposed pulp area with blue composite.

Fig. 5. Appearance of the cavity after application of the universal adhesive in the self-etch mode.

Fig. 6. Cavity filled up to the level of the interproximal enamel wall with CLEARFIL MAJESTY™ ES Flow - Super Low A2.

Fig. 7. Second visit: Prepared cavities.

Fig. 8. Situation after bonding, build-up of the interproximal walls with paste-like composite, filling with flowable material and coverage with a final layer of paste-like CLEARFIL MAJESTY™ ES-2 Classic A2.

Fig. 9. Appearance of the restored tooth before contouring.

Fig. 10. Result of the polishing procedure …

Fig. 11. … carried out with a rubber polisher and the CLEARFIL™ Twist DIA System.

FINAL SITUATION

Fig. 12. Treatment outcome …

Fig. 13. … immediately after rubber dam removal.

Dentist:

DR. ALEKSANDRA ŁYŻWIŃSKA
Warsaw, Poland

Dr. Aleksandra Łyżwińska, DMD, is a passionate aesthetic and adhesive dentist. Driven by Evidence Based Dentistry, her goal includes using modern composite materials and bonding agents in her clinical practise. In addition to her primary job, she worked as a lecturer and an assistant professor at the Department of Conservative Dentistry and Endodontics of Medical University of Warsaw, her alma mater.

Case by Dr. Jorge F. Zapata, DDS

When replacing amalgam restorations, we often see that the remaining tooth structure is severely stained. Nevertheless, a defect-oriented preparation is preferable over a procedure that involves the removal of healthy, but stained dentin as well. Long-lasting direct restorations with a natural look are obtained by using the universal adhesive CLEARFIL™ Universal Bond Quick, CLEARFIL MAJESTY™ Flow as a cavity liner, CLEARFIL MAJESTY™ ES-2 Premium Dentin to mask the stained areas and a final layer of CLEARFIL MAJESTY™ ES-2 Universal. The following case example confirms that this product combination leads to a nice optical integration.

Fig. 1 Pre-operative image: Maxillary second premolar and first molar with amalgam restorations in need of replacement.

Fig. 2 Situation after removal of the existing amalgam restorations.

Fig. 3 Immediate treatment outcome.

Dentist:

DR. JORGE F. ZAPATA, DDS

Interview with Peter Schouten, Technical Manager, Kuraray Europe Benelux

PRECISION - STRENGTH - POLISHABILITY

When creating KATANA™ AVENCIA™ Block for CAD/CAM, our goal was to develop a block that would be easy to grind while delivering a smooth surface. Of course, its mechanical properties had to be first-rate, and we aimed for excellent gloss retention. Finally, it goes without saying that KATANA™ AVENCIA™ Block restorations had to be durable as well as being suitable for adhesive cementing.

Existing hybrid ceramic blocks on the market (except for VITA™ Enamic) are produced in the same way as direct dental filling composites, namely, silanized filler mixed with synthetic resin. The composite is then formed into a block or a mold and polymerised. The disadvantages are a non-uniform distribution of the filler particles and an increased risk of trapped air which can result in voids. Instead, KATANA™ AVENCIA™ Block uses the unique Filler Press and Monomer Infiltration method, developed by Koichi Okada et al. The treatment of the filler is what makes this method so unique.

Nano-sized silica fillers pre-treated with silane combined with nano-sized alumina fillers are densely compressed into a block which is subsequently impregnated with resin. Finally, the blocks are polymerized by heat to achieve a maximized degree of polymerization. Blocks manufactured in this way have a dense, homogenous and virtually void-free structure.

SEM photos show the microstructure of KATANA™ AVENCIA™ Block, in a comparison with other materials. KATANA™ AVENCIA™ Block is filled densely and uniformly with only nano-sized filler.

Smooth

Owing to the high filler content with filler particles of up to a maximum of 40 μm, KATANA™ AVENCIA™ Block is not only strong but also extremely easy to grind. Thanks to smooth result the next step - polishing - is simplicity itself.

Strong

The KATANA™ AVENCIA™ Block is yet another example of how we have fully exploited our knowledge and expertise in the silanisation of fillers. The nano-sized, optimally silanised silica fillers establish tight connection between silica and resin-matrix. This is essential when aiming to achieve strong and stable prosthetics.

*Not a trademark of Kuraray Noritake Dental Inc.
** Test Condition: Toothbrush wear test using tooth paste. Load: 250 g.
Source: Kuraray Noritake Dental Inc.

Polishability

The dense, homogenous, and void free structure of KATANA™ AVENCIA™ Block is the reason that the high gloss easily achieved with polishing only will be long-lasting. KATANA™ AVENCIA™ Block shows virtually no reduction of gloss after tens of thousands of brushing movements in the toothbrush test.

For optimum, long-lasting and durable results, it goes without saying that KATANA™ AVENCIA™ Block restorations should be affixed with one of the products from the PANAVIA™ family.

Wouldn’t it be great to have a single dental material indicated for the treatment of all kinds of hypersensitivities? A product that effectively and durably occludes exposed dentinal tubules caused by gingival recession, dental erosion or excessive toothbrushing, but also works in the context of professional tooth cleaning, scaling and root planning, tooth whitening or restorative procedures? The fact that Kuraray Noritake Dental Inc.’s TEETHMATE™ DESENSITIZER is ideally suited for all those indications by providing lasting hypersensitivity relief is surely one of the reasons for its winning of a Dental Advisor award for the seventh consecutive year.

Designed to crystallize hydroxyapatite (HAp) from the ground up, TEETHMATE™ DESENSITIZER reliably seals exposed dentinal tubules and enamel cracks.

Consisting of natural calcium and phosphate, the product may even be applied to freshly prepared tooth structure without negatively affecting the bond strength of subsequently utilized dental adhesives or cements.

The consultants of the Dental Advisor conducted a six-month clinical study to be able to evaluate the performance of TEETHMATE™ DESENSITIZER. They selected 27 patients with hypersensitivity issues in their dental practices. Thermal testing with cold air was used to identify the affected teeth, 54 of which were included in the evaluation. For the initial assessment, patients were asked to evaluate their level and frequency of hypersensitivity per tooth on a five-point scale (1 = severe, persistent sensitivity to 5 = no sensitivity). Subsequently, TEETHMATE™ DESENSITIZER was applied according to the instructions for use. Sensitivity was evaluated again immediately after the treatment and six months later. At baseline, 91 percent of the patients stated that they had no or only mild, sporadic sensitivity, which was still the case for 85 percent after six months. This indicates that the product is very effective in providing immediate and even long-term hypersensitivity relief.

Hence, it is not surprising that TEETHMATE™ DESENSITIZER has been among the winners of the Dental Advisor’s Top Product Award every year between 2015 and 2021.

Study results that confirm the material’s effectiveness in reducing pre- and post-operative sensitivity in the context of tooth whitening¹ and indirect restoration procedures² are also available, so that users can count on a reliable performance in a wide range of indications.

References

1. Mehta D, Jyothi S, Moogi P, Finger WJ, Sasaki K. Novel treatment of in-office tooth bleaching sensitivity: A randomized, placebo-controlled clinical study. J Esthet Restor Dent. 2018 May;30(3):254-258.
2. Shetty R, Bhat AN, Mehta D, Finger WJ. Effect of a Calcium Phosphate Desensitizer on Pre- and Postcementation Sensitivity of Teeth Prepared for Full-Coverage Restorations: A Randomized, Placebo-Controlled Clinical Study. Int J Prosthodont. 2017 Jan/Feb;30(1):38-42.

Case by Dr. Aleksandra Łyżwińska, DMD

The case presented is regarding a patient with two discoloured composite restorations located in the distal aspect of the maxillary right central incisor and the mesial aspect of the adjacent lateral incisor. A replacement of these restorations was planned due to marginal leakage and for aesthetic reasons. During cavity preparation, a vestibular bevel was created in the enamel of the lateral incisor to provide for a smooth blend-in of the restoration and to improve adhesion. After selective etching of the enamel with phosphoric acid gel, CLEARFIL™ SE BOND 2 was applied. The adhesive contains the original 10-MDP monomer, which establishes a strong bond by adhering to dentin chemically. The restorations were created with CLEARFIL MAJESTY™ ES Flow - Low A2 and CLEARFIL MAJESTY™ ES-2 Classic in the shade A2. Final polishing was accomplished in a four-step procedure with abrasive discs, an aluminum oxide rubber polisher, and the two-disc CLEARFIL™ Twist DIA polishing system.

Fig. 1. Initial clinical situation after rubber dam placement.

Fig. 2. Detailed view of the teeth with a discoloured resin composite restoration visible in the mesial aspect of the lateral incisor.

Fig. 3. Palatal view of the teeth revealing marginal staining of the restoration in the distal aspect of the central incisor.

Fig. 4. Palatal view of the teeth after removal of the restorations and cavity preparation.

Fig. 5. Frontal view of the teeth after removal of the restorations and tooth preparation including beveling of the enamel.

Fig. 6. Upright placement of two sectional contoured matrices designed for the posterior region – palatal view.

Fig. 7. Frontal view of the sectional matrices fixed with a wedge.

Fig. 8. Palatal view of the teeth after selective enamel etching, bonding, and the application and light-curing of CLEARFIL MAJESTY™ ES Flow - Low A2 and CLEARFIL MAJESTY™ ES-2 Classic – A2.

Fig. 9. Frontal view of the situation - a concave “emergence profile” caused by matrix bending.

Fig. 10. Final layer of CLEARFIL MAJESTY™ ES Flow - Low A2 applied to the mesio-labial aspect of the lateral incisor.

Fig. 11. Occlusal view of the final composite layer prior to finishing.

Fig. 12. Polishing with the pre-polisher of the CLEARFIL™ Twist DIA system.

Fig. 13. Polishing with the high-shine polisher of the CLEARFIL™ Twist DIA system.

FINAL SITUATION

Fig. 14. Outcome of the polishing procedure.

Dentist:

DR. ALEKSANDRA ŁYŻWIŃSKA
Warsaw, Poland

Dr. Aleksandra Łyżwińska, DMD, is a passionate aesthetic and adhesive dentist. Driven by Evidence Based Dentistry, her goal includes using modern composite materials and bonding agents in her clinical practise. In addition to her primary job, she worked as a lecturer and an assistant professor at the Department of Conservative Dentistry and Endodontics of Medical University of Warsaw, her alma mater.