429 Too Many Requests

Case by Andreas Chatzimpatzakis

A CONCEPT EVEN FOR AESTHETICALLY DEMANDING CASES

The micro-layering technique is regarded as a more efficient, streamlined approach used as an alternative for full porcelain layering. It requires aesthetic, high-strength ceramics like lithium disilicate or zirconia as a base and – ideally – a set of porcelains specifically designed for reduced layer thicknesses that allows users to focus on imitating the characteristics of enamel. A high-quality example is CERABIEN™ MiLai (Kuraray Noritake Dental Inc.). Consisting of a set of internal stains and porcelains with a firing temperature of just 740 °C and a coefficient of thermal expansion in the range of 9.5~11.0×10-6/K (50 °C – 500 °C), this product works well on lithium disilicate and zirconia.

Its aesthetic potential is surprisingly high: Depending on case-specific requirements, users are given the choice between maximum efficiency using a single-bake technique and maximum aesthetics achieved with more complex layering. The latter option is demonstrated below using the example of six maxillary anterior veneers.

Fig. 1. Lithium disilicate frameworks (Amber Press) on the model.

Fig. 2. CERABIEN™ MiLai Value Liner 1 applied to the framework. This porcelain is typically used on lithium disilicate for wash baking.

Fig. 3. First build-up with CERABIEN™ MiLai CCV2 in the cervical section, …

Fig. 4. … Value Liner 2, …

Fig. 5. … Creamy Enamel in the middle area …

Fig. 6. … and Tx used to add ultimate translucency.

Fig. 7. Appearance of the restorations after the first bake.

Fig. 8. Outcome of the internal staining procedure.

Fig. 9. Application of CERABIEN™ MiLai LT1 for a standard translucency and opalescence effect, …

Fig. 10. … E2, …

Fig. 11. … a mixture of E2 and ELT1 (mixing ratio: 50:50) for translucency and brightness and along the marginal ridges, …

Fig. 12. … Tx mixed with Royal Blue (mixing ratio 70:30) for a blueish translucency in the incisal area…

Fig. 13. … as well as a final layer of LTx to add ultimate translucency and opalescence to the whole enamel surface.

Fig. 14. Outcome of the third bake.

Fig. 15. Cutback for the final layer of porcelain.

Fig. 16. Final layer of CERABIEN™ MiLai added to the central and lateral incisors for translucency.

Fig. 17. Situation after the fourth bake, grinding and use of a rubber polisher.

Fig. 18. Outcome of the fifth bake (self-glaze).

Fig. 19. Beauty shots …

Fig. 20. … of the restorations …

Fig. 21. … on the model.

TRULY BEAUTIFUL OUTCOMES POSSIBLE

This case example reveals that CERABIEN™ MiLai is much more than just a maximum-efficiency solution: With the current line-up of porcelains and internal stains, truly beautiful restorations can be produced. Hence, users are given high flexibility regarding not only the high-strength framework material they prefer, but also the effort and time they would like to invest. This makes CERABIEN™ MiLai a versatile porcelain system that meets many needs and covers a wide range of applications in the dental laboratory.

Dental technician:

ANDREAS CHATZIMPATZAKIS

Andreas graduated from the Dental Technology Institute (TEI) of Athens in 1999. During his studies he followed a program at the Helsinki Polytechnic Department of Dental Technique, where he trained on implant superstructures and all ceramic prosthetic restorations. As of 2000, he is running the ACH Dental Laboratory in Athens, Greece, specialized on refractory veneers, zirconia and long span implant prosthesis. In 2017 Andreas visited Japan where he trained under the guidance of Hitoshi Aoshima, Naoto Yuasa and Kazunabu Yamanda and become International Trainer for Kuraray Noritake Dental Inc..

Workflow for cementation of indirect restorations with PANAVIA SA Cement Universal and CLEARFIL Universal Bond Quick 2.

Case af dr. Julien Molia

JA, DET VIRKER!

Mange tandlæger anser flowplast for at være velegnet som liner el. base under stærkere pastakompositter og indirekte restaureringer og som provisorisk materiale. Mange af dem antager dog, at deres brug er begrænset grundet flowplasts ringe mekaniske egenskaber.

EN NY GENERATION AF FLOWPLAST

Heldigvis er dette ikke længere sandt: flere flowplastmaterialer fra den seneste generation – heriblandt CLEARFIL MAJESTY™ ES Flow og CLEARFIL MAJESTY™ ES Flow Universal (begge Kuraray Noritake Dental Inc.) – er udstyret med mekaniske egenskaber, på linje med mange pastakompositter. Indikationsområdet er udvidet som følge heraf. Eksempelvis har CLEARFIL MAJESTY™ ES Flow Universal ifølge producenten et højt fillerindhold på 75 til 78 vægt%, en bøjestyrke på mere end 150 MPa og en trykstyrke som overgår 370 MPa. Takket være produktets høje styrke tjener det som en pålidelig og permanent løsning egnet til selv spændingsbærende områder, så som kindtænders okklusalflader.

Denne flowplast har dog endnu mere at byde på: den er tilgængelig i to flydeevner – LOW og SUPER LOW – så den dækker et bredere spektrum af personlige præferencer og individuelle indikationsspecifikke behov – og dét med blot to farver (Universal og Universal Dark). Sidstnævnte gør farvevalget intuitivt, selv i det anteriore område, og er muliggjort af en blanding af teknologier til farvematch, herunder optimeret lysdiffusionsteknologi og en emaljeagtig translucens.

Følgende case viser hvordan CLEARFIL MAJESTY™ ES Flow Universal gør mit liv nemmere ved fyldningsprocedurer i kindtandsområdet.

CASE 

Amalgamfyldningerne blev fjernet og caries ekskaveret, og den sunde tandsubstans bevaret mest mulig (fig. 2 og 3). En selektiv emaljeætsningsteknik blev valgt, og en universaladhæsiv påført (CLEARFIL™ Universal Bond Quick 2, Kuraray Noritake Dental Inc.). Derefter blev kaviteterne fyldt med CLEARFIL MAJESTY™ ES Flow Universal i LOW varianten med farven U (fig. 4). Den anvendte flowplast er, takket være det innovative sprøjtedesign, praktisk talt fri for luftbobler. For at sikre komplet polymerisering overskred de enkelte lag ikke 2 millimeters tykkelse, i overensstemmelse med produktets brugsvejledning (fig. 5 og 6), hvilket har en afgørende betydning for de færdige fyldningers langtidsholdbarhed. Hvert lag bør lyshærdes grundigt i 10 til 20 sekunder (afhængigt af polymeriseringslampe), før det næste lag påføres. Som vist i figur 7, giver det anvendte materiales lave flydeevne mulighed for nogen udformning af okklusalrelieffet. Når flere anatomiske detaljer skal genskabes, kan den mere faste SUPER LOW-variant være en mulighed. Det tog blot få sekunder at pudse fyldningerne op til højglans (fig. 8).

Fig. 1. To amalgamfyldninger til udskiftning.

BRUGERVENLIGT ALTERNATIV TIL PASTAPLAST

Brugen af flowplast med velbalancerede mekaniske egenskaber kan være et godt alternativ til pastaplast, særligt i svært tilgængelige områder. Avanceret farvetilpasningsevne, en påføring praktisk talt fri for luftbobler, nem adaptering og opmodellering samt hurtig polering, gør i sandhed klinikerens liv simplere.

Dentist:

JULIEN MOLIA

CLEARFIL MAJESTY™ ES Flow Universal vinder Research Award

Egenskaberne i en nøddeskal

I Europa blev CLEARFIL MAJESTY™ ES Flow Universal lige lanceret i to flydeevner, Low og Super Low, mens den i USA er tilgængelig i Super Low varianten. For at sikre en ubesværet farvevalgsprocedure, er materialet rustet med en smart kombination af emaljeagtig translucens, dentinlignende farvemæthed og unik Light-Diffusion Technology (LDT). Dette medfører uovertrufne farvetilpasningsegenskaber og muliggør en minimal farveskala bestående af kun to supplerende farver – universal (U) og universal dark (UD). Når materialet er hærdet, tilpasser det sig naturligt den omkringliggende tandsubstans.

Udover intuitivt farvevalg byder flowplasten på en anden væsentlig fordel: dens exceptionelt høje styrke. Med en bøjestyrke på 152 MPa og en trykstyrke på 374 MPa er CLEARFIL MAJESTY™ ES Flow Universal (Super Low) lige så stærk som mange andre pasta-plastmaterialer. Som konsekvens heraf er den egnet til brug selv i belastningsbærende områder og indiceret til:

• Direkte restaureringer af alle kavitetsklasser, cervikale læsioner (fx rodcaries, V-formede defekter), tandslid og erosioner
• Kavitetsbase / -liner
• Korrektion af tandstilling og -form (fx lukning af diastema, misdannede tænder)
• Intraoral reparation af restaureringsfrakturer
• Cementering af indlæg, onlays og facader med under 2 mm’s tykkelse fremstillet af keramik eller plast.

Enestående in-vitro præstation

 CLEARFIL MAJESTY™ ES Flow Universal klarede sig meget godt på alle punkter. De fysiske egenskaber viste sig at være blandt de højeste af flowplastmaterialer og på et sammenligneligt niveau med pasta-form alternativer. Radiopaciteten blev fundet ideel, ligeledes viskositeten eftersom materialet holder sin oprindelige form efter påføring. Og selvom produktet kun findes i to farver, bekræftede bedømmerne at CLEARFIL MAJESTY™ ES Flow Universal matcher en bred vifte af naturlige tandfarver.

Om Dental Advisor

PANAVIA™ Veneer LC WINS PREFERRED PRODUCT AND RESEARCH AWARDS

PANAVIA™ Veneer LC has been singled out for a Research Award in the category Research – Veneer Cement by Dental Advisor and for a Preferred Product Award in the category Cement: Esthetic Resin. Published in the January/February 2025 issue of the US-based organisation, the annual Top Product, Preferred Product or Research Awards are given to those materials and devices deemed by the publication’s consultants to deliver the best practice-based or lab-based performance in their categories.

BENEFITS IN A NUTSHELL

PANAVIA™ Veneer LC is a specialized veneer cement designed to provide exceptional bond strength to various substrates, along with outstanding gloss retention and wear resistance. The resin cement utilizes smaller-diameter spherical filler particles, facilitating easy dispensing from the syringe and excellent flowability for minimal film thickness. All of these attributes contribute to virtually no change in gloss or surface appearance of veneer margins over time.

EXCELLENT PROPERTIES IN VITRO

To assess the scientific performance of PANAVIA™ Veneer LC, its features and physical properties, specifically its bond strength to various substrates after artificial aging and its wear resistance, were tested in the Dental Advisor Biomaterials Research Center. The investigators’ testing of these attributes reflects the challenges such products must meet – “Ideally, esthetic veneer cements should have a long working time, curing on demand, excellent color stability, and high strength”.

To assess bond strength to dentin, enamel, IPS e.max CAD, and zirconia, the cements were subjected to six months of artificial aging using thermocycling. To test wear resistance after toothbrush abrasion, the testing method involved measuring depth of wear, change in surface roughness, and change in gloss based on a simulation of about 5.5 years of regular toothbrush use.

The investigators reported that PANAVIA™ Veneer LC “had the best gloss retention of the three cements tested and a very even wear pattern,” noting further that “having limited surface roughness after toothbrush abrasion can help lower staining and bacterial adhesion.” Overall, they said, “The PANAVIA™ Veneer LC cement system showed excellent adhesion properties and exceptional gloss retention and wear resistance,” concluding:

OUTSTANDING RATING OF 96 PERCENT

In addition, the product was tested in the clinical setting. 25 clinical evaluators used PANAVIA™ Veneer LC cement system in their dental offices. After a total of 166 uses, the light-curing resin cement received “excellent” to “very good” ratings with regard to completeness of the kit, the shade of the try-in pastes, ease of clean-up of the try-in pastes and excess cement, viscosity, working time and lack of shade shift after curing.

The evaluator’s clinical tips included:

• „Use a micro brush or rubber tip to clean up excess cement before curing.”
• „Apply glycerin gel to the margins after placing the veneer with the cement to eliminate the oxygen inhibition layer and ensure a complete cure before light curing through the gel.”

In their comments, they praised the ease of use of the system, the design of the syringes, the shade options and shade match between try-in and cement shades, e.g.:

• “The white shade of the cement was opaque enough for efficient masking of discolored tooth structure.”
• “Great esthetics, very easy to use, complete system.”

This resulted in an overall clinical rating of 96 percent and an equally high recommendation rate.

ABOUT DENTAL ADVISOR

The Top Product and Preferred Product Awards from Dental Advisor, a US-based organization, were initiated to help busy practitioners navigate the variety of new dental solutions available, particularly for less invasive techniques and standardized procedures. These awards aim to identify products that improve outcomes consistently. Dental Advisor conducts clinical evaluations and product performance tests shortly after a product’s launch and publishes annual results online to help practitioners identify high-quality dental materials suited to their specific needs. Research Awards were initiated to honour those manufacturers of dental products with an ongoing commitment to research, development and advancement of dental materials to enhance treatment quality.

For more information, visit Dental Advisor at: www.dentaladvisor.com

Interview with the team at Kuraray Noritake Dental Inc., who developed and brought to life this new universal adhesive.

Streamlining, enhancing and refining adhesive procedures – these are the aims of an 5-person team at Kuraray Noritake Dental Inc. in Japan. Recently, the team has developed a next-generation universal adhesive CLEARFIL™ Universal Bond Quick 2 that offers quick and easy application combined with an optimised bonding performance. To learn more about the goals and achievements of the development project, and the benefits of the product, we had a conversation with them.

From left to right: Ryo Matsuura and Ryota Murayama (R&D Department), Kazutoshi Ikeda (Production Department), Marina Okada and Yamato Nojiri (Planning & Development Department).

Why did you decide to improve CLEARFIL™ Universal Bond Quick?

Universal adhesives like CLEARFIL™ Universal Bond Quick are very well received by dental practitioners all over the world mainly due to their versatility and procedural simplicity. In the clinical setting, however, we have identified room for improvement. For example, it can be difficult to establish thin, uniform and strong bonding layers with the currently available products. Water and solvents in universal adhesives often limit the formation of a strong bond layer. A thin bonding layer and the relatively thick oxygen inhibition layer make this type of bonding agent susceptible to degradation by water sorption from dentinal moisture. Highly viscous bonding agents also complicate the ease of application in small cavities and can easily lead to pooling of the adhesive in critical parts of the cavity. Adhesives with a relatively high viscosity may pool or accumulate along margins, and may form a layer that is too thick and may change the morphology of the abutment tooth, a critical factor potentially affecting the fit of an indirect restoration. Generally, bonding agents with a low film thickness and/or are low-filled or unfilled, in turn have a potentially negative effect on the strength of the bonding layer. At Kuraray Noritake Dental Inc., we wanted to address the aforementioned issues and have developed a universal adhesive that is easy to apply and facilitates the establishing of thin, uniform bonding layers exhibiting high strength.

What are the indications of CLEARFIL™ Universal Bond Quick 2?

The new universal adhesive is indicated for bonding procedures in the context of creating direct restorations with light-cured composite, sealing of a prepared cavity or abutment tooth as a pretreatment for indirect restorations, treatment of exposed root surfaces and hypersensitive teeth, and also the intraoral repair of fractured restorations. Furthermore, the product is a suitable adhesive in post-cementation and core build-up procedures as well as in adhesive cementing of indirect restorations. When used in the context of the cementing of indirect restorations, the bonding to tooth structure of PANAVIA™ SA Cement Universal and of other manufacturers’ self-adhesive resin cements improves, leading to higher bond strengths.

What are the corresponding general benefits of CLEARFIL™ Universal Bond Quick AND CLEARFIL™ Universal Bond Quick 2?

The general benefits of both products are that they may be used with any etching procedure, plus the fact that there is no need to wait for the adhesive to penetrate the tooth structure after application. In addition, both products contain the original MDP monomer and the amide monomer, responsible for the formation of a thin and strong surface coating. Both products exhibit low technique sensitivity and are suitable for a wide range of indications. Finally, the adhesive monomers and fluoride offer extra protection to the underlying dentin.

Monomer image from the brochure

You mentioned the original MDP monomer as one of the essential components of the new adhesive and its predecessor. Is there a difference between this original MDP monomer and other MDP monomers available on the market?

Our MDP monomer is the only MDP monomer that is manufactured using the originally developed synthesis and purification process. Research has shown that the way MDP is manufactured has indeed an impact on the performance of the monomer itself1. While impurities and dimers detected in MDP monomers synthesized elsewhere negatively affected the immediate and aged micro-tensile bond strength in the in-vitro study, our MDP monomer shows high purity and more favourable test results.

Most universal adhesives need to be rubbed into the tooth structure extensively for 10 to 20 seconds. What did you do to eliminate the waiting time independent of the etching procedure, which led to an ultra-quick application procedure?

It is the amide monomer which is mainly responsible for an improved penetration speed into the tooth structure. The hydrophilicity of this monomer is much higher than the hydrophilicity of the HEMA monomer that is typically used. This provides for a better penetration into the moist dentin. The amide monomer’s polymerisation characteristics are better, and, following polymerisation, leads to higher stability in a wet environment due to the formation of a highly cross-linked polymer network. In combination with MDP, an efficient long-term performance will likely be achieved. For optimal outcomes, the adhesive is simply rubbed into the tooth structure as described in the IFU: “Apply BOND with a rubbing motion to the entire cavity wall with the applicator brush. No waiting time is required.”

What are the additional benefits that CLEARFIL™ Universal Bond Quick 2 has to offer?

First of all, we improved the viscosity and film thickness by optimizing the manufacturing method. The thin adhesive layer prevents pooling in the cavity, around abutments and along margins, creating a uniform bonding layer. Simply put, the new adhesive is applied thinly and spreads evenly. At the same time, the product offers high mechanical strength and excellent resistance to water sorption. Its bond strength is high in all etching modes and the new formulation allows for the product to be stored at room temperature.

Please explain the clinical benefit of an improved mechanical strength.

The risk of decreasing the film thickness lies in a possible decrease in the strength of the bonding layer which can lead to reduced bond durability. By introducing a new multifunctional urethane methacrylate monomer, we have been able to increase the strength. The effective advantage of the new bonding agent is that it can easily be used in small, difficult-to-access cavities or in cavities with complex morphology. The result is a thin yet strong adhesive layer that also allows for easy placement of any type of restoration.

How did you manage to improve the storage conditions?

Component stability was not an issue with CLEARFIL™ Universal Bond Quick. However, for a stable viscosity, it needed low-temperature storage. By optimizing the manufacturing method and decreasing the viscosity of CLEARFIL™ Universal Bond Quick 2, storage at room temperature became possible.

Was it difficult to integrate the new components and keep the existing benefits? How did you manage?

Integrating new components and removing others always means that the whole formulation needs to be rebalanced properly. This was particularly challenging for the multifunctional urethane methacrylate monomer we wanted to add. It improves the strength and hardness of the universal adhesive, but may affect adhesion depending on the amount of the compound in the formulation. Consequently, we needed to carefully find optimal balance, which took some time and required thorough testing, but in the end, we succeeded.

At the moment, the immediate dentin sealing technique is popular in indirect restoration procedures. What makes CLEARFIL™ Universal Bond Quick 2 suited for this technique?

Immediate dentin sealing is indeed a popular and useful technique that can result in significantly increased retention, reduced marginal leakage, improved bond strength, and less postoperative sensitivity. Using CLEARFIL™ Universal Bond Quick 2 in this context is beneficial as the procedure is quick, the resulting bonding layer is thin and strong, and the dentin is effectively protected.

Why should a dental practitioner switch to CLEARFIL™ Universal Bond Quick 2?

For users of CLEARFIL™ Universal Bond Quick, switching to CLEARFIL™ Universal Bond Quick 2 is worthwhile, as it offers additional advantages and improved performance while retaining the benefits of its predecessor. For users of other universal adhesives, the major benefit lies in the shortened application time: CLEARFIL™ Universal Bond Quick 2 is the only universal adhesive that can achieve a high bond strength and a high-strength bonding layer without any waiting time. In addition, it is suitable for a wide range of indications including core build-up procedures and cementation.

Thank you very much for these insights!

References
1. Yoshihara K, Nagaoka N, Okihara T, Kuroboshi M, Hayakawa S, Maruo Y, Nishigawa G, De Munck J, Yoshida Y, Van Meerbeek B. Functional monomer impurity affects adhesive performance. Dent Mater. 2015 Dec;31(12):1493-501.