Optimizing Chemical Properties for a Truly Universal Adhesive

Alex's passion for dental education comes from his personal experience of graduating from Tufts University School of Dental Medicine in 1981 and entering into dental practice alongside his father. "My father was a practicing dentist for almost 50 years, and one of the many things that I learned from him was that to excel in dentistry, you have to be passionate about dentistry, and that means making a commitment to continuing education and improving your diagnostic and clinical skills," he says. According to Alex, one of the most important things that a young dentist can do is to find mentors, whether it's by establishing relationships with more experienced dentists or joining organizations of like-minded individuals. "All of us need someone to help guide us, to bounce ideas off of, and to go to for support and advice," he says.

In addition to working alongside his father, Alex sought out many other educational opportunities and mentors when he was a newly graduated dentist. In 1986, he took a 3-day course with Ronald Goldstein, DDS, which introduced him to the then emerging field of cosmetic dentistry. "I knew instantly that this was the direction I wanted to go in," Alex says. In 1987, he joined the American Academy of Cosmetic Dentistry, which at the time, was just a fledgling organization. "It was there that I learned many of the clinical skills that I needed to do the type of dentistry that I wanted to do," Alex says. "I became friends with a number of outstanding dentists and mentors, including BISCO's founder, Byoung Suh, PhD. I already had a fairly good background in chemistry, and when Dr. Suh saw that I had an interest and passion for understanding how adhesive systems worked, he not only encouraged me but also spent countless hours helping me learn and understand the nuances of the chemistry involved."

Alex began integrating BISCO products into his practice, and when All-Bond Universal^® was introduced in 2012, he was one of the first practitioners to use it. "Even though I had access to a number of adhesive systems, I started routinely using All-Bond Universal in my practice just prior to its official introduction," he says. "I had tested many, but All-Bond Universal became my system of choice."

All-Bond Universal is a single-bottle, no-mix, adhesive system with 10-MDP that is designed to be used in total-etch, self-etch, or selective-etch mode depending on the specific clinical situation and personal preferences of the operator. In addition, it can be used for the placement of both direct and indirect restorations and is compatible with self-cure, light-cure, and dual-cure resin-based cements, which Alex says is not true of all universal adhesives. He explains that All-Bond Universal can also be used as an adhesive primer on substrates such as zirconia, noble and non-precious metals, and composites. "My personal preference is to use All-Bond Universal in the total-etch mode or the selective-etch mode if any enamel is present," he says. "If the pulp is exposed, a pulp capping product, such as TheraCal LC^®, should be used first."

The chemical properties of All-Bond Universal were of particular interest to Alex. He notes that many universal adhesives utilize the same basic chemistry in some regards. For example, almost all use the 10-MDP monomer. However, there are subtle but important differences that can give certain products advantages over others. "The pH, initiator and solvent chemistry, and specific monomer types and ratios are some of the chemical properties that differ across universal adhesives," Alex says. In the case of All-Bond Universal, having a slightly higher pH than other universal adhesives is of benefit. "There is a direct correlation between pH and the compatibility of universal adhesives with self- and dual-cure resin cements and composites," he explains. "As a generalization, the more acidic the adhesive is, the less compatible it is with the self-cure mode of dual-cure resin-based materials. Because of this, many universal adhesives require the use of a separately bottled ‘activator' that must be mixed with the adhesive in order for it to be used in conjunction with many self- and dual-cure resin cements." When compared with the 2.0 to 3.0 pH range of many universal adhesives, All-Bond Universal has a less acidic pH of 3.2, which allows it to be used in all situations without a separate activator.

Alex emphasizes that developing a successful adhesive system is really all about achieving the right balance of chemical properties. "The multifunctional monomers must be able to copolymerize with chemically compatible resin-based restoratives and cements and have some hydrophilic character in order to properly ‘wet' dentin that has a significant water content," he says. "At the same time, the adhesive must be as hydrophobic as possible once polymerized to discourage hydrolysis and water sorption over time. The film thickness of the polymerized adhesive must also be thin enough to not interfere with the seating of indirect restorations, and the adhesive should be acidic enough to effectively self-etch but not so acidic that it breaks down the initiators needed to polymerize self- and dual-cure resin cements."

Although there are many complex factors involved in developing a great universal adhesive, Alex feels confident because the chemists at BISCO are knowledgeable experts who have taken all of these chemical properties into consideration. "All-Bond Universal has been carefully optimized to ensure the best results" he says.

• All-Bond Universal is not moisture sensitive and can be used on wet, dry, or moist tooth structure.

• Bonds to all substrates, and with a film thickness of less than 10 μm, it can be used for all direct and indirect restorations.

• The chemical balance is ideal for both total- and self-etch adhesion from a one-bottle system.

• All-Bond Universal is compatible with all resin cements, with no additional activator required, and results in virtually no postoperative sensitivity.

For more information, contact:
Bisco, Inc.
bisco.com • 800-247-3368