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Welcome to the latest edition of BOND Magazine, your essential guide to cutting-edge advancements and techniques in the world of dentistry. Volume 11 is packed with insightful articles, expert interviews, and practical advice designed to enhance your dental practice or laboratory and keep you at the forefront of the profession.

In this issue, we dive into the simplicity and predictability of the flowable injection technique with Michał Jaczewski. Learn how this minimally invasive method can transform patient outcomes with minimal preparation, making it accessible for both beginners and experienced practitioners alike.

We also explore the transformative potential of universal resin cement in Prof. Lorenzo Breschi's article, which introduces a third application mode that could revolutionize how you approach luting for challenging restorations.

Meanwhile, Dr. Michael Braian shares his comprehensive guide to dental rehabilitation using digital workflows, ensuring you can leverage the latest technology for superior patient care.

This volume also includes a case reports by Dr. Jose Ignacio Zorzin - discussion on rationalizing clinical procedures with universal adhesives. These insights will help streamline your workflows, reduce chair time, and enhance patient satisfaction.

From detailed explorations of high-performance materials to interviews with leading dental laboratory professionals like Alexander Aronin and Andreas Chatzimpatzakis, BOND Magazine offers a wealth of knowledge for all dental professionals.

Click here to read. Enjoy reading, and let us inspire your journey towards excellence in dentistry.

Start Reading: BOND | VOLUME 11 | 07/2024

Previous versions:

BOND | VOLUME 10 | 10/2023

BOND | VOLUME 9 | 08/2022

BOND | VOLUME 8 | 12/2021

BOND | VOLUME 7 | 10/2020

By Dr. Adrien Lavenant

In many clinical situations, composite restorations offer advantages over all-ceramic restorations. The treatment is less costly, usually less invasive, and the restorations can be modified and repaired at any time. When it comes to restoring multiple teeth, however, a free-hand layering approach used to build up every tooth separately can be very time-consuming and labour-intensive. In these situations, the flowable injection technique –also referred as injection moulding – is a great alternative. It is minimally invasive, suitable as a temporary or permanent solution to issues around tooth wear and irregular shape, and time-efficient in the clinical setting.

Essential materials

While the planning phase including the creation of the wax-up can be accomplished in the traditional way or in the digital workflow and components may differ depending on the preferred way of working, two materials are essential for the implementation of the flowable injection technique: A transparent silicone and a flowable composite. The silicone is used to produce an index and transfer the planned shape of the restorations from the wax-up into the patient’s mouth. Transparency is needed to make sure that the flowable composite will be cured properly through it – an important precondition for high-quality results. The flowable composite is injected into the silicone index. While offering a great flow behaviour during injection, the selected material should also exhibit a high mechanical stability for durability. CLEARFIL MAJESTY™ ES Flow Low (Kuraray Noritake Dental Inc.) offers the desired properties. One possible way to combine the materials and implement the technique is illustrated using the following patient case.

Important step in a complex treatment

This patient came to the dental office after orthodontic treatment with a request to improve the aesthetics of her smile. In the maxillary and mandibular anterior region (incisors and canines), severe tooth wear was diagnosed, with the maxillary central incisors most severely affected (figs. 1 to 4). To restore her maxillary teeth as quickly as possible, the least invasive immediate treatment option was selected: A smile makeover with composite using the flowable injection technique. In the long term, it is planned to perform a full-mouth rehabilitation with all-ceramic restorations.

Fig. 1. Initial situation: Lateral view from the right.

Fig. 2. Initial situation: Lateral view from the left.

Fig. 3. Initial situation: Frontal view.

Fig. 4. Close-up of the severely worn central incisors.

Shade determination and index production

After an analysis of the tooth colour using two different methods (figs. 5 and 6), a digital impression was taken and a wax-up designed with dedicated CAD software. The wax-up model was then printed (fig. 7); it served as the basis for the production of the transparent silicone index (figs. 8 and 9). After complete curing of the material, injection channels were integrated at the incisal edges of each tooth to be restored.

Fig. 5. Determination of the tooth colour using a shade guide.

Fig. 6. Picture taken with a white_balance grey reference card for objective shade quantification.

Fig. 7. 3D-printed model of the upper jaw with the virtually designed wax-up.

Fig. 8. Silicone index produced over the wax-up model with injection channels at the incisal edges of each tooth.

Fig. 9. Close-up view of the index with injection channels.

Shade validation and preparations for injection

To validate the selected shade, small amounts of composite (buttons) in three different shades were applied to the untreated surface of the left central incisor and cured (fig. 10). In this way, it is possible to visualize the colour of the composites in the mouth. The selected shade was A1. The aprismatic enamel layer on the surfaces of the six maxillary anterior teeth was carefully removed with burs to create ideal bonding conditions (fig. 11). The teeth were then isolated with clear matrix strips for the implementation of the bonding protocol on the right canine and central incisor and left lateral incisor: To provide for proper interproximal separation and contacts, it is advisable to treat every other tooth and then repeat the procedure for the rest. The teeth were etched with phosphoric acid, rinsed and carefully dried before applying the selected adhesive (CLEARFIL™ SE PROTECT, Kuraray Noritake Dental Inc.) (fig. 12). For separation and protection of the adjacent teeth during composite injection, PTFE tape is a great choice (fig. 13).

Fig. 10. Composite buttons applied to the left central incisor for shade validation.

Fig. 11. Roughened tooth surfaces.

Fig. 12. Etched and bonded surfaces of the right canine, right central incisor and left lateral incisor after isolation with clear matrix strips.

Fig. 13. Protection of the adjacent teeth with PTFE tape.

Composite injection and treatment of the other teeth

After its application, the silicone index was placed in the mouth and CLEARFIL MAJESTY™ ES Flow Low in the shade A1 injected tooth by tooth through the injection channels (fig. 14). What followed was proper light curing of the composite through the index. The situation after index removal is shown in figure 15. At this stage, the excess still needed to be removed, before protecting and separating the already restored teeth with PTFE tape and repeating the procedure for the other lateral incisor, central incisor and canine.

Fig. 14. Index with injected composite.

Fig. 15. Result after index removal.

Treatment outcome

Once all the excess material was completely removed, the occlusion was checked and adjusted. Finishing and polishing was accomplished with TWIST™ DIA for Composite (Kuraray Noritake Dental Inc.). The immediate treatment outcome is shown in figures 16 to 18, while figures 19 and 20 were taken at a recall after six months.

Fig. 16. Treatment outcome: Frontal view.

Fig. 17. The new smile.

Fig. 18. Treatment outcome: Occlusal view.

Fig. 19. Appearance of the teeth…

Fig. 20. … at the six-month recall.

Conclusion

Thanks to advances in restorative materials and technological tools, it is nowadays possible to restore our patients' smiles quickly and reproducibly. The flowable injection technique is one of the most successful examples of modern aesthetic treatments using composite resin. CLEARFIL MAJESTY™ ES Flow has all the qualities needed to carry out these treatments under the right conditions.

About the Author

Dr. Adrien Lavenant obtained his degree in Dentistry from Aix-Marseille University in 2010. He pursued post-university training in periodontology, implantology, and restorative and aesthetic dentistry (Aix-Marseille University and Paris). Dr. Lavenant has been a former teaching staff member at Aix-Marseille University since 2011 and continues to teach in the postgraduate programme in restorative and aesthetic dentistry. He practices in his private clinic in Aix-en-Provence, specializing in restorative, prosthetic, and aesthetic implant dentistry. He has been a member of the international Bio-Emulation group since 2019 and shares his patient care philosophy in accordance with the principles of biomimetic dentistry.

Case report by Dr. Wissam Dirawi, DDS

During the last decade, zirconia has increasingly established itself as the material of choice in oral prosthodontic rehabilitation. Its great mechanical and inert properties are the main reason for this trend. Since the introduction of multi-layered zirconia blanks more than ten years ago, the optical properties have been improved dramatically. The multi-layered zirconia used nowadays (e.g. KATANA™ Zirconia YML from Kuraray Noritake Dental Inc.) offers well-balanced mechanical properties, translucency and colour. It allows dental technicians from all over the world to produce aesthetic full-contour restorations that are merely stained.

Even in the anterior region, stained monolithic restorations may be an option. Factors such as the age of the patient, the internal colour structure of the adjacent dentition, the number of teeth to be restored (one versus all four or six maxillary anterior teeth), the aesthetic demands of the patient and financial aspects should be taken into account in the material selection process. In the case described below, full-contour zirconia was selected for several reasons.

BACKGROUND

The 71-year-old female presented in the clinical due to aesthetic problems in the maxillary anterior region. Oral hygiene was good and the patient was a non-smoker. Infraposition of the existing implant-based crown (Nobel Biocare Brånemark RP fixture) in the position of the right central incisor (tooth #11 according to the FDI notation) was evident. Moreover, gingival retraction was observed on the maxillary right lateral incisor (tooth #12), while the left lateral incisor (tooth #22) has a major composite filling with discolouration. The patient expressed the desire to adjust the gingival level differences and to restore the four maxillary incisors with all-ceramic crowns for optimal aesthetics.

Fig. 1. Initial situation: Frontal view.

Fig. 2. Initial situation: Facial view.

Fig. 3. Initial situation: Occlusal view of the maxilla.

Fig. 4. Initial situation: Occlusal view of the mandible.

MATERIAL SELECTION

Due to the decision to restore all four anterior incisors, monolithic zirconia was a suitable material option. It would allow the team to obtain the desired results within the financial framework. In order to meet the aesthetic demands of the patient, provide for the required mechanical properties and allow for proper masking of the underlying structures, KATANA™ Zirconia YML was selected. It offers colour, translucency and flexural strength gradation throughout the multi-layered blank.

TREATMENT PROCEDURE: FROM PREP TO TEMPORIZATION

In order to design the indirect restorations, a digital impression was taken with an intraoral scanner and the data was transferred to the dental laboratory Teknodont in Malmoe, Sweden. There, a digital wax-up was created. After patient approval, a matrix was produced and sent to the clinic. Here, the old restorations were removed and the three maxillary incisors (all but the one replaced by an implant) prepared for full coverage restorations. A healing abutment was placed on the implant and a temporary bridge produced chairside using the matrix and Protemp 4 Temporization Material (3M) in the shade A3. Subsequently, a gingivectomy was carried out with a ceramic burr (Ceratip, Kt.314.016 – KOMET) in the buccal aspect of the left central and lateral incisor.

Fig. 5. Chairside-produced temporary in the patient’s mouth.

After the patient’s approval of the aesthetics, phonetics and function of the temporary restoration, the situation was captured with an intraoral scanner again. This allowed the team to duplicate the shape of the construction. Based on the acquired data, a new set of splinted temporary crowns made of PMMA (HUGE Multilayer PMMA) in the shade A3 was milled in laboratory. They were placed to allow the patient to further evaluate the aesthetic appearance and function for a couple of weeks. The patient was happy with the phonetics, function and appearance of the crowns, which were merely slightly too bright in comparison to the adjacent teeth, and approved the shape for the production of the permanent restorations.

Fig. 6. Printed model …

Fig. 7. … with splinted PMMA crowns.

Fig. 8. Lab-made temporary restorations.

Fig. 9. Long-term temporary in place: Lateral view from the right.

Fig. 10. Long-term temporary in place: Frontal view.

Fig. 11. Long-term temporary in place: Lateral view from the left.

FINAL RESTORATIONS: PRODUCTION AND CEMENTATION

Based on the dataset of the temporary restorations, four separate crowns – one implant and three tooth-based – were designed in full contour. Without any anatomical reduction, the restorations were milled from KATANA™ Zirconia YML. Based on the evaluation of the temporary restoration, the shade selected this time was A3.5. CERABIEN™ ZR FC Paste Stain was used for external staining and glazing of the surface. Still in the laboratory, the implant-based crown was cemented to the gold-shaded titanium abutment (Elos Medtech) with PANAVIA™ V5 (Kuraray Noritake Dental Inc.) in the shade opaque for an improved masking effect.

While the abutment crown was screwed onto the implant and the screw hole closed with composite, the three tooth-based crowns were placed using PANAVIA™ SA Cement Universal (Kuraray Noritake Dental Inc.).

Fig. 12. Final restorations on the model.

Fig. 13. Intraoral situation prior to restoration placement.

CONCLUSION

Multilayered zirconia is a suitable material for many clinical situations. Due to the availability of modern types of highly translucent, multi-layered blanks, it is possible to produce aesthetic outcomes even when using the material monolithically – not only in the posterior region, but also in the aesthetic zone in some indications. The present case shows that very good results and patient satisfaction can be obtained. And due to outstanding mechanical properties, these outcomes may be expected to last for a long time.

Fig. 14. Immediate treatment outcome: Facial view.

Fig. 15. Immediate treatment outcome: Frontal view.

Fig. 16. Immediate treatment outcome: Occlusal view.

Dentist:

WISSAM DIRAWI

Dr. Wissam Dirawi, Malmoe, Sweden. DDS.
Specialist in Oral Prosthodontics and Senior Adviser at Aqua Dental.

2000 Master´s degree in dentistry.
2000 - 2018 General Dentist in public dental care and private practice.
2011 - 2018 Part-time teacher and researcher at Malmö University, Faculty of Dentistry.
2018 Specialist in Oral Prosthodontics. Senior clinical adviser. Lecturer.

References

- Alfadhli R, Alshammari Y, Baig MR, Omar R. Clinical outcomes of single crown and 3-unit bi-layered zirconia-based fixed dental prostheses: An up to 6- year retrospective clinical study: Clinical outcomes of zirconia FDPs. J Dent. 2022 Dec;127:104321.
- Le M, Papia E, Larsson C. The clinical success of tooth- and implant-supported zirconia-based fixed dental prostheses. A systematic review. J Oral Rehabil. 2015 Jun;42(6):467-80.
- Alammar A, Blatz MB. The resin bond to high-translucent zirconia-A systematic review. J Esthet Restor Dent. 2022 Jan;34(1):117-135.
- Sadowsky SJ. Has zirconia made a material difference in implant prosthodontics? A review. Dent Mat 2020; 36: 1–8.
- Mazza LC, Lemos CAA, Pesqueira AA, Pellizzer EP. Survival and complications of monolithic ceramic for tooth-supported fixed dental prostheses: A systematic review and meta-analysis. J Prosthet Dent 2022; 128: 566–74.
- Passia N, Mitsias M, Lehmann F, Kern M. Bond strength of a new generation of universal bonding systems to zirconia ceramic. J Mech Behav Biomed Mater. 2016; 62:268–274.
- Sailer I, Makarov NA, Thoma DS, Zwahlen M, Pjetursson BE. All-ceramic or metal-ceramic tooth- supported fixed dental prostheses (FDPs)? A systematic review of the survival and complication rates. Part I: Single crowns (SCs). Dent Mater 2015; 31:603-623.
- Pjetursson BE, Sailer I, Makarov NA, Zwahlen M, Thoma DS. All-ceramic or metal-ceramic tooth- supported fixed dental prostheses (FDPs)? A systematic review of the survival and complication rates. Part II: Multiple-unit FDPs. Dent Mater 2015; 31:624–639.

By Manabu Suzuki, Director of Dental Division, Kuraray America, Inc.

Kiyoko Ban, a prominent figure in the dental technology field, has made a lasting impact as a researcher, developer, and founder of Noritake Dental business (Fig. 1). Renowned for her contributions to dental porcelains like Noritake's CZR and EX-3, and KATANA™ Zirconia, Ms. Ban stands as a pivotal force in the global advancement of dental technology, earning her the esteemed reputation of developer and marketer within the dental technology community.

After completing her university education in Nagoya, Ms. Ban initially assisted in her family's gas station business. However, driven by a desire for a career change, she enrolled in a newly established dental technician college in Nagoya at the age of 30. Her aspiration was to enter a field where gender distinctions held no sway, offering the potential for worldwide recognition based on technical mastery.

In 1977, a college-sponsored tour to American dental laboratories ignited Ms. Ban's dream to work in the United States. However, she delved into research across various fields such as chromatology (the science of color), ceramics and metals, finding a newfound passion for research over clinical work after graduation because she was offered a "Curriculum Chief" position from the college when she graduated (Fig. 2).

Fig. 2. Ms. Ban, a curriculum chief at the Dental Technicians College, devoted her evenings to material research.

Fig. 3. In the 1990s, Ms. Ban actively engaged in promoting EX-3 through sales efforts in Italy.

Her teaching career spanned from the age of 34 to around 40, during which she pioneered porcelain training sessions for technical improvement and arranged lectures over weekends by famous speakers such as Masahiro Kuwata.

At the age of 40, she resigned teaching career and pursued her research career. The opportunity to conduct full-scale experiments led her to the discovery of a company with advanced ceramic technology "Noritake Co., Limited", renowned for its tableware. In 1986, Cusp Dental Supply, a research institute, was established by Ms. Ban in Nagoya, focusing on the development of materials for PFM crowns. The commercialization of Super Porcelain AAA (EX-3) in 1987 marked a significant milestone, addressing issues prevalent in porcelain materials of that time, such as cracks, greening, and fluorescence.

She began traveling all over Japan and around the world to sell the products she had developed and went on to develop new products that were needed by dental technicians worldwide (Fig. 3). She continued to develop new products such as CZR, CZR Press, and KATANA™, the world's first multilayer zirconia.

Ms. Ban has been actively involved in mentoring students and graduates seeking opportunities to work overseas. During summer vacations, she took students and professionals interested in working abroad to countries like Australia, Germany, and the United States. The aim was to visit dental clinics, dental technician schools, and laboratories, fostering exposure and learning in an international context.

Simultaneously, Ms. Ban delved into researching non-precious dental technology. Inspired by her exposure to the term "non-precious" during her time in the United States, she anticipated its potential in Japan. Her research presented at lectures and events highlighted the shift in the landscape as the price of gold surged, rendering precious alloys containing significant amounts of gold impractical for PFM crowns.

As the demand for their developed products grew, the need for global acceptance became apparent. In 1990, Cusp Dental Research was established in Manhattan, New York, marking Ms. Ban's foray into establishing a company overseas. Despite the unfamiliarity with legal procedures and the challenges of setting up a foreign company, Ms. Ban, driven by determination, overcame these hurdles. The establishment of the company in the United States expanded their presence internationally Fig. 4).

Fig. 4. Capturing the essence of ISC 1996 - the International Symposium on Ceramics in Orlando, FL..

Noritake Dental Supply Co., Limited was established in 1998 by the Noritake Co., Limited, which aimed to further expand its dental business. Despite the absence of a capital relationship with Noritake at the time of establishing the research laboratory, Ms. Ban played a key role in joint research efforts with Noritake. Then she was invited to this company as the position of president, owning 60% of the stock, while Noritake held 40% (Fig. 5).

Besides Noritake Dental business, she continued expansion with the establishment of a dental laboratory in Boston in 1995. Despite the challenges posed by the September 11, 2001 World Trade Center incident, they acquired their building in Boston, integrating their New York laboratory into the Boston operations.

Ms. Ban's tenure as president of Noritake Dental Supply persisted until 2009, but organizational changes following the merger with Kuraray in 2011 led to her transition into an advisory role (Fig. 6). Despite the shift in responsibilities, her commitment to the dental technician profession remained steadfast.

Fig. 5. Noritake Dental Supply Inc Inauguration Party, 1998.

Kiyoko Ban's path encapsulates not just a career but a legacy in the field of dental technology. From her early struggles in a tooth carving class to establishing and expanding international laboratories, Ms. Ban's story is one of determination, innovation, and a deep-rooted commitment to advancing the dental technician profession.

Fig. 6. A scene from Ms. Ban’s retirement celebration as Noritake Dental Supply president, surrounded by esteemed dental technicians from around the world.

UNFORGETTABLE WEEK

In April, a team from Kuraray Noritake Dental’s European arm accompanied 18 Key Opinion Leaders (KOLs) from Germany, Italy, Spain, France, Turkey, Poland, England, Romania, Switzerland, the Czech Republic, and Denmark to Kuraray Noritake Dental’s roots in Japan. The week was an incredible blend of professional exchange, cultural immersion, and shared experiences.

The European group included an interdisciplinary team of dentists, dental technicians, professors, and researchers. They toured Kuraray Noritake Dental’s two production sites in Niigata (chair-side manufacturing) and Nagoya (lab-side products) and visited the Head Office in Tokyo.

Visit to the production facility for chair-side products in Niigata.

INTERDISCIPLINARY AND INTERNATIONAL EXCHANGE

As you can imagine, this was a fantastic opportunity for both Kuraray Noritake Dental’s European employees and KOLs to have lively exchanges with Japanese developers and production personnel. Our KOLs highly appreciated the opportunity to present their own work and ongoing results while sharing tips and techniques with the Japanese members.

The importance of this trip for both the KND employees and the European travel group was underlined by the participation of the Head of Kuraray Noritake Dental (Yamaguchi-san) and the inventor of Noritake dental porcelain (Kiyoko Ban). In her welcome speech, she emphasized what an extraordinary opportunity this interdisciplinary and international exchange represents and how pleased she was about the numerous visitors.

Kiyoko Ban during her welcome speech for the delegation from Europe.

Head of Kuraray Noritake Dental (Yamaguchi-san) together with Dr. David Gerdolle, Jakab Daniel, and Honoré Morel during lunch in the Tokyo office.

The tour proved that there really is no substitute for face-to-face, hands-on interaction when it comes to discussions between product developers and specialists as well as seeing behind the scenes for a direct insight into production and quality assurance.

As Dr David Gerdolle said: “Kindness, perfect organization, dedication to precision and professionalism are a rare and precious combination in the actual world. My deepest gratitude to the Kuraray Noritake company for this unforgettable week in Japan.”

EXPLORING JAPAN

However, the visit wasn’t all about work. There was a fabulous opportunity to see Mount Fuji in all its glory on the train ride from Nagoya to Tokyo and as well as a unique chance to explore Japanese culture. Not to forget the visit to Noritake Garden in Nagoya, where the history and traditional art of fine tableware through to modern high-tech materials are on display.

Exhibitions at the Noritake Museum in Nagoya.

As Daniel Dunka (MDT) said: “The whole trip was absolutely wonderful, and I’m grateful to Noritake for the invitation. It has been a wonderful experience mingling with colleagues from all over the world in such a beautiful environment. It has been an inspiration for me and I look forward to continuing to work with your wonderful materials and of course your amazing team.

Jakab Daniel (MDT) added: “The organizational culture [in Japan] is fascinating, it is amazing to be a part of the whole manufacturing process of Noritake ceramics, Zirconium KATANA and all Kuraray products. Very good discussions, opinions, suggestions” while MDT Mathias Berger from France summed up the whole visit with: “Thank you so much for your invitation, I realized a dream.” 

Vikten av högkvalitativ protetisk behandling

Högkvalitativ behandling är förmodligen den viktigaste faktorn för patientnöjdhet. Under varje enskilt tandläkarbesök vill patienten känna sig väl omhändertagen av skickliga yrkesmänniskor, men antalet sittningar får gärna hållas på en minimum. Vid protetisk behandling förutsätter det att ersättningen måste passa perfekt direkt och att den är hållbar över tid för att undvika omgörningar och extra tandläkarbesök.

Men är det ens möjligt att leverera perfekt passande och högkvalitativa ersättningar varje gång? Bland de potentiella källorna till problem med kvaliteten hos indirekta ersättningar finns vanliga misstag som görs av både tandläkare eller laboratoriet, kommunikationsmissar och ett ofta förbisett problem; användning av ågkvalitativt zirkonia.

Zirkoniaersättningar - en modern och estetisk lösning

För över tjugo år sedan gjorde zirkonia entré på den dentala marknaden som en ersättning för den metall som användes för att framställa kronor och broar. Båda materialen - zirkonia och metall - användes vanligen i kombination med ytporslin - i form av metallkeramiska konstruktioner eller porslinspåbrända zirkoniakonstruktioner. Under efterföljande år fokuserade ledande tillverkare av dentalt zirkonia (som Kuraray Noritake Dental Inc.) på materialförbättringar. Dessa förbättringar ledde gradvis till att det ursprungligen opakvita zirkoniamaterialet, som användes för underkonstruktioner, utvecklades till ett keramiskt material med tandlika optiska egenskaper och utmärkta mekaniska egenskaper. De senaste varianterna av zirkonia, som finns att få i olika graderav translucens och styrka, betraktas av många tandläkare jorden runt som det bästa möjliga behandlingsalternativet för en stor grupp patienter med varierande egenskaper och behov. En anledning är att materialet inte kräver någon, eller väldigt lite, porslinspåbränning. En annan anledning är att materialet tillåter tunn godstjocklek, vilket i sin tur möjliggör mycket måttlig avverkning av tandsubstans vid preparation. Vidare erbjuder materialet - förutsatt att ett högkvalitativt zirkonia används - ett gynnsamt långtidsresultat.

Det är skillnad i kvalitet mellan olika sorters zirkonia

Kvaliteten på olika zirkoniaprodukter kan variera beroende på olika faktorer; råmaterialets renhetsgrad (det gäller inte bara zirkonia, utan också alumina och yttria, liksom olika färgtillsatser osv.), precisionen i den kemiska sammansättningen, kornstorlek och partikeldistribution. Varje steg i framställningen av zirkoniaämnet - från pulversammansättning till pressning av ämnet till försintring - påverkar också kvaliteten på slutprodukten, d.v.s. de mekaniska och optiska egenskaperna hos zirkoniamaterialet.

Vanliga problem som orsakas av lågkvalitativ zirkonia

Varje gång det är något fel på de optiska egenskaperna hos en ersättning - med translucens, färg eller med övergångarna från ett lager till nästa i ett flerskiktat ämne - blir problemet uppenbart efter slutsintringen, som sker på det tandtekniska laboratoriet. Det blir kanske nödvändigt med en omgörning och till slut uppdagas kanske felet under inprovningen, vilket sannolikt har en negativ påverkan på patientens upplevelse. Detsamma gäller i de fall passformen blir felaktig på grund av till exempel orenheter i materialstrukturen. Och vad värre är; sämre egenskaper för biokompabilitet, ytstruktur, kantstabilitet, böjhållfasthet och brottseghet. De egenskaperna är bara identifierbara med mycket dyr testutrustning, som inte finns att tillgå på ett tandtekniskt laboratorium. Det betyder att brister av det slaget inte upptäcks förrän kliniska problem - som gingival recession, ökad ansamling av plack, högre grad av slitage eller frakturer som kan orsaka smärta och obehag - uppstår.

Översikt; potentiella problem och klinska konsekvenser för patienten

Certifiering och standardisering av dental zirkonia

Det är därför specialister har utvecklat en ISO-standard (ISO 6872:2015), som beskriver de in-vitrotester som alla tillverkare av zirkonia för dentalt bruk i Europa och USA måste genomföra för att bli godkända av FDA och för att få CE-märka sin a produkter. Testerna används för att mäta böjhållfasthet och brottseghet, de två sannolikt mest betydelsefulla egenskaperna för hur ersättningar som framställts av materialet beter sig över tid. Alla material som används i Europa och USA måste klara de här testerna.

Hur du undviker att sätta lågkvalitativa zirkoniaersättningar i munnen på dina patienter

Därav borde alla som använder certifierad zirkonia kunna känna sig säkra och kapabla att undvika materialrelaterade risker. Den ökade populariteten hos dental zirkonia har dock attraherat aktörer som vill ha sin bit av kakan utan att behöva anstränga sig för att säkra en hög produktkvalitet eller för att genomgå certifiering. Icke-certifierade produkter som saknar CE-märkning har en sak gemensamt: de försätter både din verksamhet och dina patienter i fara.

Så hur är det möjligt att säkra zirkoniaprodukternas kvalitet från tandläkarkliniken? De goda nyheterna är att det finns några enkla regler tillgängliga. Genom att följa dessa regler kan du undvika att sätt falsifikat och undermåliga produkter i munnen på dina patienter.

Sätt inte falisifikat eller produkter av lågkvalitativ zirkonia i munnen på dina patienter.

Tre gyllene regler du ska följa för att förse dina patienter med högkvalitativa zirkoniaersättningar:

• Beställ bara ersättningar som framställts här hemma eller från en region som lyder under samma regelverk som du som själv: ersättningar som produceras i t ex Kina behöver inte uppfylla samma höga krav (därav avsaknaden av CE-märkning) och lever kanske därför inte upp till dina förväntningar.
• Prata med ditt (inhemska) laboratorium om var deras zirkonia kommer ifrån: försäkra dig om att de köper sitt zirkoniamaterial från ledande tillverkare (som Kuraray Noritake Dental Inc.) via auktoriserade återförsäljare eller säljare som de verkligen känner.
• Undvik erbjudanden som är för bra för att vara sanna: låga priser kan vara frestande, men den slutligiltiga prislappen för behandlingen kan bli ännu högre än vanligt när komplikationer uppstår.

Betydelsen på lång sikt för patienterna vid bruk av certifierade zirkoniaersättningar

Att försäkra sig om att det zirkoniamaterial du använder i kliniken uppfyller högsta möjliga kvalitetskrav är ett viktigt bidrag till patientnöjdheten över tid. Även om den initiala kostnaden för högkvalitativa zirkoniaersättningar är något högre än för ersättningar av lägre kvalitet, kan den totala investeringen bli mindre eftersom ersättningarna håller längre och omgörningar inte behövs. Dina nöjda patienter kommer sannolikt att vara mera engagerade och följsamma i att sköta sin munhygien och de förblir lojala, med positiv påverkan på ditt rykte och din patientstock.

Undersök olika val av zirkonia och välj produkter från certifierade tillverkare

Om du vill gå ett steg till kan du till och med jämföra olika certifierade zirkoniamaterial från olika tillverkare och upptäcka skillnader. Kurary Noritake Dental Inc. är till exempel en av de få tillverkare av zirkonia som "äger" hela tillverkningsprocessen, vilken inkluderar egen produktion av råmaterial. På så sätt har företaget kontroll över varje steg i processen och det ger en enstående produktkvalitet - oavsett vilken variant av materialet man väljer. Med produktportföljen som består av KATANA™ Zirconia UTML (ultratranslucent, flerskiktad), KATANA™ Zirconia STML (extra translucent flerskiktad) och det högtranslucenta, flerskiktade HTML PLUS liksom YML (med ytterligare styrka och translucensgradient), är det möjligt att svara upp mot varje indikation.

Artikel av professor Lorenzo Breschi

Färre förpackningar, fler val - det är det enklaste sättet att beskriva universalresincement. Eftersom de är självadhesiva tillåter dessa dualhärdande, resinbaserade cement ett arbetsflöde med en komponent - utan separata primers för tand eller ersättning - i flertalet kliniska situationer. Den bindningsstyrka som uppnås är vanligtvis hög nog för att säkra en stabil bindning mellan tand och ersättning - i ett brett spann av indikationer. Det är dock något svagare än den bindning som erhålls med konventionella resincement, bestående av flera komponenter (vanligen primer för tand, resincement och primer avsedd för ersättningen).

Förutom att användas för självadhesiv cementering, kan resincement användas med kompletterande komponenter för att öka bindningsstyrkan till tand och/eller ersättning. Detta öppnar upp för nya möjligheter för användning av produkten: beroende på vilka bindningsegenskaper som önskas eller krävs, kan resincementet användas ensamt eller i kombination med primer för tand och/eller primer för ersättning. På så sätt blir hybridkoncept möjliga. Detta förklaras i den här artikeln som använder PANAVIA™SA Cement Universal (Kuraray Noritake Dental Inc. som exempel.

Självadherande cementering: för flera indikationer

När PANAVIA™ SA Cement Universal används som självadherande cement är detta dualhärdande resincement mycket användbart i många situationer. Bindningen till de restorativa materialen (inklusive kiselbaserade keramer) är hög, utan användning av separata primers eller silan1-4. Det beror på de två adhesiva monomerer som ingår i formulan - Original MDP-monomeren och LCSi-monomeren (ett silanbindningmedel med långa kolkedjor som ger en stark kemisk bindning till kiselbaserade keramer) Därför kan resincementet användas utan att ytterligare komponenter tillförs på det protetiska materialet - inte ens när det saknas retention och kravet på stark bindning därför är ännu högre.

Den självadherande användningen ger också en stark bindning till emalj och dentin. I vissa situationer kan dock användning av tandprimer användas för att ytterligare stärka bindningen till tandstrukturen

Adhesiv cementering: för utmanande situationer

För användning tillsammans med PANAVIA™ SA Cement Universal rekommenderas CLEARFIL™ Universal Bond Quick (Kuraray Noritake Dental Inc.). Primer för tanden rekommenderas när användaren bedömer att behandlingsresultatet kommer att gynnas av en extraordinärt stark och hållbar kemisk bindning, d.v.s, i särskilt utmanande situationer där det föreligger otillräcklig mekanisk retention. Effektiviteten hos denna åtgärd har bekräftats i en japansk in-vitrostudie, i vilken mikrodraghållfastheten i bindningen till dentin efter 24 timmar hade ökat signifikant genom användning av universaladhesiven5. När man använder en separat adhesiv ökar dock kravet på noggrann och fullständig torrläggning. Anledningen till detta är att resincement är mindre fuktkänsliga än adhesiver. Därför anbefalls användning av kofferdam vid adhesiv användning.

Selektiv adhesiv cementering: för låga abutments och subgingivala kantanslutningar

För situationer där korrekt isolering med kofferdam är svårt, finns ett tredje alternativ tillgängligt - framtaget av en grupp italienska forskare: Selektiv Adhesiv Cementering. I det här fallet appliceras CLEARFIL™ Universal Bond Quick enbart i de preparerade tandområden som tillåter adekvat kontroll av fukt, medan man i de områden där fuktkontrollen är en utmaning förlitar sig på den självadhesiva funktionen hos PANAVIA™ SA Cement Universal. Situationer som lämpar sig för den här tekniken är typiskt sett stödtänder med subgingival preparationsgräns och fall där stödtanden är särskilt kort (så kort att den förhindrar användning av kofferdam).

Effektiviteten hos selektiv adhesiv cementering har verifierats i en in-vitrostudie, som jämförde tre olika adhesiva metoder - självadherande cementering, helomfattande adhesiv cementering och selektiv adhesiv cementering - med hjälp av draghållfasthetstest6. Testresultaten visar att bindningsstyrkan mellan PANAVIA™ SA Cement Universal och dentin respektive emalj ökas genom att adhesiven appliceras på enbart en del av tandens yta. För cementeringssystemet som består av PANAVIA™ SA Cement Universal och CLEARFIL™ Universal Bond Quick, uppvisade den helomfattande adhesiva cementeringen och metoden att selektivt cementera adhesivt liknande resultat.

En grupp italienska forskare föreslår ett tredje alternativt för de situationer när ordentlig torrläggning av arbetsområdet är svårt: Selektiv Adhesiv Cementering.

REKOMMENDERADE STEG FÖR SELEKTIV ADHESIVE CEMENTERING

Fig. 1: Preparerad tand

Fig. 2: Selektiv emaljetsning med fosforsyra.

Fig. 3: Applicering av universaladhesiv + luftblästring

Fig. 4. Resincementet appliceras inuti kronan och kronan sätts på plats.

Fig. 5. Punktvis härdning

Fig. 6. Avlägsnande av överskott och slutlig ljushärdning.

Fig. 7. Behandlingsresultat vid 1-årskontroll.

Fördelarna med selektiv adhesiv cementering

Förutom den eftersträvansvärda (långtids)ökningen i bindningstyrka som man uppnår genom att använda selektiv adhesiv cementering för en del av den preparerade tandytan, erbjuder metoden en del andra fördelar. Jämfört med de cementeringssystem som består av flera steg är protokollet förenklat, eftersom ingen separat primer behövs. Ljushärdning av adhesiven är inte nödvändigt så länge man använder sig av det rekommenderade systemet. Behovet av användning av kofferdam är eliminerat vid användning av den metoden för selektiv adhesiv cementering. På så sätt minskar tiden i tandläkarstolen och patientens bekvämlighet ökar.

Sammanfattning

Beroende på indikation, kliniska variabler och individuella preferenser kan användare av resincement, som PANAVIA™ SA Cement Universal, välja den metod som sannolikt ger det bästa kliniska resultatet. Det är den här flexibiliteten och det breda utbudet av användningsområden som gör den här innovativa produktkategorin i sanning universell. Med färre komponenter som ska användas underlättar universalprodukter strömlinjeformning och standardisering av kliniska procedurer, och det blir färre förpackningar som ska lagras, vilket underlättar beställning och lagerhållning.

Tandläkare:

LORENZO BRESCHI

Professor Lorenzo Breschi undervisar i protetik och dentala material vid universitetet i Bologna. Han är aktivt delaktig i forskning på de ultrastrukturella aspekterna av emalj och dentin. Han är tidigare president för The Academy of Dental Materials (ADM), ordförande för European Federation for Conservative Dentistry (EFCD), ordförande för Dental Materials Group (IADR), ordförande för Italian Academy for Conservative Dentistry (AIC), ordförande för International Academy of Adhesive Dentistry (IAAD).

Referenser

1. Cowen M, Cunha S, Powers JM. Novel Cement Bond Strength to Multiple Substrates. DENTAL ADVISOR Biomaterials Research Center, Biomaterials Research Report, Number 132 – June 16, 2020.
2. Patel N, Anadioti E, Conejo J, Ozer F, Mante F, Blatz M. Bond Strength of Different Self-Adhesive Resin Cements to Zirconia” (2021). Dental Theses. 62. https://repository.upenn.edu/dental_theses/62.
3. Yoshihara K, Nagaoka N, Maruo Y, Nishigawa G, Yoshida Y, Van Meerbeek B. Silane-coupling effect of a silane-containing self-adhesive composite cement. Dent Mater. 2020 Jul;36(7):914-926.
4. Irie M, Tokunaga E, Maruo Y, Nishigawa G, Yoshihara K, Nagaoka N, Minagi S, Matsumoto T. Shear bond strength of a resin cement to CAD/CAM Blocks for molars. P-2, 37th Annual Meeting of the Japanese Society of Adhesive Dentistry 2018.
5. Ohara N. Bonding strength of resin cement containing silane coupling agent to dentin or core resin. Results presented at the 150th meeting of the Japanese Society of Conservative Dentistry.
6. Breschi L, Josic U, Maravic T, et al. Selective adhesive luting: A novel technique for improving adhesion achieved by universal resin cements. J Esthet Restor Dent. 2023;1-9. doi:10.1111/jerd.13037.

Available Now!

Have you ever produced a zirconia restoration without obtaining the outcome you expected? Most dental technicians probably have. The bad thing is that aesthetic flaws such as colour deviations or white spots and technical issues like cracks can occur and require remakes. The good thing is, however, that those problems are usually avoidable. Do you know how?

We would like to show you – in the new KATANA™ Zirconia Troubleshooting Handbook we just completed. On 30 pages, this handbook summarized the most important facts about modern zirconia-based restorative materials, their selection, the KATANA™ Zirconia line-up and, finally, possible aesthetic or technical problems, their origin and solutions to overcome them.

Let us assume that the beauty of your restorations is limited due to a lack of translucency. By looking up the problem “lack of translucency”, you will find a compact, well-structured overview of possible causes and adequate solutions. The recommendations include selecting dry instead of wet milling, abstaining from sandblasting the restoration surface and checking of the sintering parameters, quality of the sintering beads and position of the restoration in the furnace. For more details, problems and solutions, download the handbook!

DOWNLOAD NOW

Article by Prof. Lorenzo Breschi

Fewer bottles, more choices – this is possibly the shortest way to describe the category of universal resin cements. Being self-adhesive, these dual-cure resin-based cements allow for a single-component workflow without the need for separate tooth or restoration primers in many clinical situations. The bond strength obtained in this way is usually high enough to provide for a stable bond between the tooth and the restoration in a wide range of indications. However, it is slightly lower than that achieved with conventional resin cement systems consisting of several components (typically tooth primer, resin cement and restoration primer).

Apart from the self-adhesive application mode, universal resin cements may be combined with additional system components to increase the bond strength to tooth structure or the restorative material, respectively. This opens up new possibilities with regard to the product’s use: depending on the required or desired bonding performance, the universal resin cement may be applied alone or in combination with a tooth primer, a restoration primer or both components. In addition, hybrid concepts become feasible, as explained in this article that focuses on PANAVIA™ SA Cement Universal (Kuraray Noritake Dental Inc.) as an example.

Self-adhesive luting: for many indications

PANAVIA™ SA Cement Universal is a dual-cure universal resin cement that is indicated for a wide range of applications when used in the self-adhesive mode. The bond established to restorative substrates (including silicate ceramics) is high without the use of a separate primer or silane^1-4. This is due to two different adhesive monomers contained in the formulation – the Original MDP Monomer and the LCSi Monomer (a long carbon-chain silane coupling agent responsible for a strong chemical bond to silicate ceramics). Hence, it is possible to use the resin cement without any additional component applied on the side of the restoration – even in cases with a lack of retention and consequently high bond-strength requirements.

A strong bond to enamel and dentin is also obtained in the self-adhesive mode. In certain situations, however, it may be useful to further increase the bond strength to tooth structure with the aid of a tooth primer.

Adhesive luting: for challenging situations

The tooth primer recommended for PANAVIA™ SA Cement Universal is CLEARFIL™ Universal Bond Quick (Kuraray Noritake Dental Inc.). Its application is recommended whenever a user feels that the treatment would benefit from an extraordinarily strong and durable chemical bond, i.e. in particularly challenging situations with insufficient mechanical retention. The effectiveness of this measure has been confirmed in an in-vitro study conducted in Japan, in which the 24-hour micro-tensile bond strength to dentin was increased significantly by the application of the universal adhesive⁵. When a separate adhesive is used, however, the importance of a completely dry working field increases. The reason is that the moisture tolerance of resin cements is usually higher than that of adhesives. Consequently, the application of a rubber dam is highly recommended.

Selective adhesive luting: for short abutments and subgingival margins

For situations in which proper isolation of the working field with a rubber dam is difficult, a third application option is available and proposed by a group of Italian researchers: Selective Adhesive Luting. In this case, CLEARFIL™ Universal Bond Quick is applied solely to those parts of the prepared tooth that allow for proper moisture control, while relying on the self-adhesive functionality of PANAVIA™ SA Cement Universal in areas where it is challenging to obtain the desired dry working field. Situations which are predestined for this technique are abutment teeth with a subgingival preparation margin and particularly short abutment teeth (that hinder the placement of a rubber dam).

The effectiveness of the selective adhesive luting technique has been verified in an in-vitro study that compared the three adhesive strategies – self-adhesive luting, full adhesive luting and selective adhesive luting – with the aid of shear bond strength testing⁶. The results of the tests show that users are able to enhance the bond strength of PANAVIA™ SA Cement Universal to dentin and enamel by applying the adhesive to a part of the tooth surface only. For the cementation system consisting of PANAVIA™ SA Cement Universal and CLEARFIL™ Universal Bond Quick, the full adhesive and the selective adhesive approach led to similar outcomes.

For situations in which proper isolation of the working field with a rubber dam is difficult, a third application option is available and proposed by a group of Italian researchers: Selective Adhesive Luting.

RECOMMENDED STEPS FOR SELECTIVE ADHESIVE LUTING

Fig. 1. Tooth preparation.

Fig. 2. Selective etching of the enamel with phosphoric acid etchant.

Fig. 3. Application of the universal adhesive + air-drying.

Fig. 4. Crown placement after application of the resin cement into the crown.

Fig. 5. Tack-curing.

Fig. 6. Excess removal and final light curing.

Fig. 7. Treatment outcome at a recall after one year.

Benefits of selective adhesive luting

Apart from the desired (long-term) increase in bond strength achieved by applying a separate adhesive to a part of the or the whole prepared tooth surface, the technique offers additional benefits. Compared to multi-step cementation systems, the protocol is simplified as no separate restoration primer is needed. Light-curing of the adhesive is not required as long as the user stays within the recommended system. And in contrast to the full adhesive approach requiring rubber dam placement, the need for this step is eliminated in the selective adhesive approach. In this way, the chair-time is reduced and patient comfort increased.

Conclusion

Depending on the indication, clinical variables and individual preferences, users of universal resin cements like PANAVIA™ SA Cement Universal may select the technique that is likely to deliver the best clinical outcomes. It is this flexibility and the generally wide range of applications that makes the innovative product category truly universal. With fewer components to be used, universal materials facilitate the streamlining and standardization of clinical procedures, while with fewer bottles to be stored, they help staff gain control over order and storage management as well.

Dentist:

LORENZO BRESCHI

Prof. Lorenzo Breschi is Professor of Restorative Dentistry and Dental Materials at the University of Bologna. He is actively involved in research on the ultrastructural aspects of enamel and dentin. He is Past-President of the Academy of Dental Materials (ADM), President-Elect of the European Federation of Conservative Dentistry (EFCD), President-Elect of the Dental Materials Group IADR, President-Elect of the Italian Academy of Conservative Dentistry (AIC), President-Elect of the International Academy of Adhesive Dentistry (IAAD).

References

1. Cowen M, Cunha S, Powers JM. Novel Cement Bond Strength to Multiple Substrates. DENTAL ADVISOR Biomaterials Research Center, Biomaterials Research Report, Number 132 – June 16, 2020.
2. Patel N, Anadioti E, Conejo J, Ozer F, Mante F, Blatz M. Bond Strength of Different Self-Adhesive Resin Cements to Zirconia” (2021). Dental Theses. 62. https://repository.upenn.edu/dental_theses/62.
3. Yoshihara K, Nagaoka N, Maruo Y, Nishigawa G, Yoshida Y, Van Meerbeek B. Silane-coupling effect of a silane-containing self-adhesive composite cement. Dent Mater. 2020 Jul;36(7):914-926.
4. Irie M, Tokunaga E, Maruo Y, Nishigawa G, Yoshihara K, Nagaoka N, Minagi S, Matsumoto T. Shear bond strength of a resin cement to CAD/CAM Blocks for molars. P-2, 37th Annual Meeting of the Japanese Society of Adhesive Dentistry 2018.
5. Ohara N. Bonding strength of resin cement containing silane coupling agent to dentin or core resin. Results presented at the 150th meeting of the Japanese Society of Conservative Dentistry.
6. Breschi L, Josic U, Maravic T, et al. Selective adhesive luting: A novel technique for improving adhesion achieved by universal resin cements. J Esthet Restor Dent. 2023;1-9. doi:10.1111/jerd.13037.

May 15th, 2024 at 21:00 CET

From margin elevation to restoration

Did you ever wonder how to optimize teamwork, efficiency, and patient satisfaction in the context of a combined endodontic and restorative treatment? As a general or restorative dentist, you can easily contribute to streamlined procedures and better outcomes for your patients. The measures to be taken are in the center of this webinar by experienced and knowledgeable Dr. Wiktor Pietraszewski.

Endodontic treamtment and pre-refferal strategies

In the first part of his lecture, Dr. Pietraszewski reveals how to proceed before referring the patient to the endodontic specialist to improve the overall prognosis of the treatment on the one hand, and the patient experience on the other. Materials and techniques, such as deep margin elevation, caries removal, and tooth build-up, will be described and examined. But most importantly, many practical tips will be shared with the audience.

Post-endodontic restoration options for long term success

In the second part, the speaker will focus on post-endodontic treatment. He will describe the available materials and types of post-endodontic restorations. Dr. Pietraszewski will shed light on the most important factors guiding the most crucial treatment decisions and will elaborate on the factors influencing long-term success.

Go to the Facebook Event of the webinar and click „Livevideo”!

We look forward to seeing you!

About the speaker

Dr. Pietraszewski is a general and restorative dentist working in private practice in London. He utilizes biomimetic adhesive protocols in his restorative cases and uses gold standard materials to emulate the natural appearance, bio-mechanical function, and internal structure of teeth when restoring them.

He has a special interest in direct and indirect restorations in the posterior dentition, and his dentistry is fueled by his passion for dental photography.

From The Medical University in Lodz (Poland) to private clinics in Malta and London, his dental journey reflects dedication to excellence.