KEY PROPERTIES OF MODERN ONE-STEP BONDING AGENTS AN INTERVIEW WITH DR TOMOHIRO TAKAGAKI DDS PHD

Due to its increased usability, one-step universal adhesivesare becoming more popular and the choice of many clinicians all around the world. Nonetheless, some studies have shown a lower performance than previous generations.
Jorge Espigares, DDS, PhD, Planning and Development Department at Kuraray Noritake Dental, interviewed Tomohiro Takagaki, DDS, PhD, lecturer and former assistant professor at Tokyo Medical and Dental University (TMDU), pioneer in the field adhesive dentistry, author of many publications and currently lecturer at Asahi University

Dr. Espigares: Dr. Takagaki, in your opinion, what are the most important factors for a good and durable adhesion?

Dr. Takagaki: Good resin infiltration (penetration) and good polymerisation are essential factors for good bonding. This is the basic concept for the formation of the hybrid layer. Additionally, there are other important factors such as low water sorption for bonding durability and the demineralization depth, which should be the same as the depth that the resin is capable of penetrating to. Dr. Espigares: Nowadays, the trend seems to be one-step universal adhesives. Do you believe that this reduction in steps has brought any limitations compared to previous generations? Dr. Takagaki: Traditionally, one-bottle adhesives are too hydrophilic. This hydrophilicity also brings high water sorption, therefore the durability of the interface is compromised. At TMDU, we did not accept one-step bonding agents in clinical use based on results we obtained in our research in that area.

Dr. Espigares: What do you think of the new MDP-Amide chemistry (included in CLEARFIL Universal Bond Quick) for overcoming such limitations?

Dr. Takagaki: The MDP monomer has proved through research to be the best monomer for adhesion to tooth substrate. Nowadays, many manufacturers include MDP. Although the MDP purity and performance differs from Kuraray Noritake’s original one, in one-step bonding agents only MDP is not enough. The differential factor is the amide monomer that provides the desired high penetration and low water sorption.

Dr. Espigares: You and your work at TMDU, are very well known in the field of adhesive dentistry. Did your research show results that would support the abovementioned statements?

Dr. Takagaki: In our research results, we observed indeed a lower water sorption compared to previous one-step generations. Actually, we were surprised to see water sorption levels equivalent to the two-step bonding agent gold standard: CLEARFIL SE BOND. The amide monomer behaves as hydrophilic before the polymerization and as hydrophobic after, which is the desired situation for one bottle, self-etching systems. Dr. Espigares: Would you therefore recommend the usage of universal bonding agents in daily practice? Dr. Takagaki: Yes, but as mentioned, the MDP-amide chemistry is essential. It is noteworthy that another company is also using an amide monomer. However, our results at TMDU indicate that the performance in terms of penetration is not that good. Actually, we still saw lesion formation with that other company’s amide. Kuraray Noritake’s MDP-Amide chemistry is the only one that avoids lesion formation.

Dr. Espigares: Let’s get out of the laboratory. According to your clinical experience, is there any extra advice that you could provide for reliable adhesion?

Dr. Takagaki: One important point that sometimes is missed is to properly air-dry the solvent for at least 5 seconds after the bond application. I also recommend selective enamel etch for achieving aesthetic margins, even if all universal bonding agents allow self-etching. Finally, I would like to talk about simplicity. We dentists tend to shorten the necessary time and sometimes the rubbing time is not respected. With Universal Bond Quick, our research showed no significant difference in bond strength with rubbing time is not respected. With Universal Bond Quick, our research showed not significant difference in bond strength and the rubbing time. Therefore, it reduces the risk of error, allowing consistent results. I believe that simplicity is required so the fact that Universal Bond Quick and PANAVIA SA Cement Universal can cover direct and indirect restorations is ideal for daily practice. Universal Bond Quick achieves what I am looking for in my practice: easy, quick, and reliable. Although the universal adhesive market is large, key properties like the above-mentioned may help in the complicated process of selecting a one-step adhesive that offers the best performance, simplicity, consistency and predictable results.

Latest Blog Articles

Earned Placement: Art and Architecture Inspire a 2021 Townie Choice Award Recipient

The Carriere Motion 3D Appliance is the recipient of the 2021 Orthotown Townie Choice Award, and the Carriere Motion 3D Clear Appliance earned the Gold Delta Design Award from the ADI-FAD. Recognized for its aesthetic design, the Carriere Motion 3D for Class III correction is on permanent display at the Barcelona Museum of Design. Dr. Carrière is the inventor of the Carriere Motion 3D Appliance for both Class II and Class III correction, as well as Carriere SLX 3D⁷Self-Ligating Brackets. Inventor, educator and practicing orthodontist, Dr. Carrière speaks about the development of the Motion 3D Appliance and the reasons behind its wide acceptance.

Ultrasonic Cleaning: Getting It Right

In mid-2023, leading up to and then following the release in December 2023 of the new Australian Standard 5369 on reprocessing reusable medical devices, I had been working on updating the ADA’s Infection Prevention and Control Guidelines for what would become their May 2024 fifth edition. This was part of my role of serving as the editor of those Guidelines, something I have done since 2010. Given that the new standard placed considerable role on local facility risk assessments, I had been undertaking some deep analysis work to identify areas of failure that could occur in a dental practice that was reprocessing instruments on site. From looking at the literature and also from reviewing my own experience auditing dental practices, it became clear that the topic of ultrasonic cleaning was not as well understood by end users as it should be. It is also one where I felt that there was considerable work yet to do.

Optizyme Ultra D: An Advanced Tool for Dentistry

Novapharm has been a research leader in the use of enzyme detergent medical instrument reprocessing for 3 decades. The last 15 years has seen an almost total replacement of the old style alkaline detergents by near neutral enzyme detergent formulations which have proven to be safer, more efficacious, more cost effective and more instrument compatible.

Why NZ Dental Practices should adopt Piezotome Technology like the Acteon CUBE

In the rapidly advancing field of dental surgery, ensuring patient safety, comfort, and optimal clinical outcomes is a priority for any modern dental practice. One technology that is making a significant impact in achieving these goals is piezotome technology, such as the Acteon CUBE. For NZ dental practices, adopting this innovation could elevate the standard of care across a range of procedures, including bone surgeries, extractions, sinus lifts, crest splitting, and crown extensions.

Managing Dentine Hypersensitivity with MI Varnish

MI Varnish™ features a hydrogenated rosin matrix that ensures high fluoride, calcium and phosphate ions availability, combined with translucency and exceptional durability. This enhanced formulation means MI Varnish™ can provide exceptional protection from dentine hypersensitivity.

New to Henry Schein?

Existing Customers

Search Results for

Filter By

All Results

Article