An Interview with: Sibel Antonson, DDS, PhD, MBA

Inside Dental Technology (IDT): What areas of clinical research do you believe will have the most significant impact on restorative dentistry in the future?

Sibel Antonson, DDS, PhD, MBA (SA): Certainly, the current research into smart dental materials promises to have a significant long-reaching impact on the practice of dentistry and patients’ oral health. These materials are designed to actively interact with the oral environment. For example, bioactive dental restoratives deliver caries preventive agents to teeth while acting as the direct restorative and/or adhesive agent. However, many of today’s “smart” materials are technique-sensitive and therefore ineffective if applied incorrectly. The goal would be to develop materials that would require only one step to apply and would integrate fully and directly with tooth tissues.

IDT: Could you provide an example of how these new smart materials could change the practice of dentistry and indirect restorative procedures?

SA:Research is looking into how to develop a four-phase smart dental material that can be used to treat patients in any stage of disease. Phase one of the material would be designed to make the tooth structure completely caries-resistant for patients with no carious lesions. It would be applied to the tooth surface before caries form. Phase two of the material would reverse the caries process in patients whose teeth exhibit early caries formation or for patients with a high risk of caries.

If the tooth were to exhibit late-stage caries, the third material phase would not be technique-sensitive. If a dentist chooses a direct restorative material, then it should be one that can fuse with tooth tissues, eliminating the need for technique-sensitive cements or bonding agents. If that same tooth needed a crown or bridge restoration, the fourth phase would be a smart indirect restorative material. It would fuse directly with tooth tissue, eliminating the need for adhesive retention and concerns about degradation, marginal fit, tooth sensitivity, or the compatibility of interface materials.

IDT: What do you see as the next step in indirect ceramics development?

SA:Currently, our research is focused on developing high-strength monolithic ceramics that are suitable for creating single crowns and long-span posterior bridges. Our challenge is to make the material strong enough to withstand the working forces of the posterior region without creating connector sizes that compromise the esthetics and periodontal health of the tissue.

Therefore, we are concentrating on developing a lithium disilicate ceramic that can be milled and fused to a zirconia bridge substructure. Our goal is to achieve the same translucency and shade levels in the material so that we can serve any need from very high translucency to very high opacity with a single material. The zirconia substructure and milled ceramic will be fused using a ceramic material so that the final restoration will be a fully integrated one-piece structure that is kind to opposing dentition and cannot fail.

IDT: If strength and connector size is a major issue for fabricating long-span bridges, why not consider milled full-contour zirconia as the final restoration?

SA:We certainly have looked at that possibility and currently we have the technology to offer this option. However, the use of full-contour zirconia restorations is very new and there is not sufficient clinical data to predict the long-term effects of these restorations. The concern is the wear of the opposing enamel. Once the protective glaze is compromised, we have found in our simulation laboratory that the underlying zirconia can be very destructive to natural enamel. Keep in mind that the study results we have seen are not conclusive. We need independent, evidenced-based clinical studies to provide us with definitive answers.

IDT: What is the ultimate goal of biomaterials research?

SA:Research ultimately aims to change the chemistry of the tooth completely to make the tooth disease-resistant. Caries is the most widespread infectious disease in the world. We know that there are certain types of bacteria that cause caries. At birth, we have none of these caries-causing bacteria in the mouth. Parents and relatives transmit them when they kiss the baby on the mouth or when they share contaminated utensils or pacifiers with the baby. For caries to form, bacteria need sugar. When bacteria digest sugar, the by-product is the acid that dissolves and erodes tooth enamel and causes caries. So, if we can break this cycle or change the oral flora or sugar content somehow, we can reduce the rate of caries.

We are committed to continuing to develop materials that meet the needs of the world’s changing dental population. We want to discover techniques and materials, and now more importantly, biological and chemical materials that interfere with bacterial initiation, adherence, and growth. Remineralizing materials will continue to reverse the caries process—prevention is our primary goal. When prevention fails, then the creation of user-friendly materials must be stressed. Research should be aimed at having dental biomaterials that require the least amount of mechanical preparation, have long-term adherence, wear-resistance, esthetics, and remineralizing capacities.

About the Author

Sibel Antonson, DDS, PhD, MBA
Director of Professional Services
Ivoclar Vivadent
Buffalo, New York

Clinical Associate Professor and Director
Dental Biomaterials
SUNY at the University of Buffalo’s School of Dental Medicine
Buffalo, New York