Scientists working to develop more durable, cheaper restoratives

March 9, 2020

Neutron scattering research, which is a frequently used method in modern science that is used to understand material properties on an atomic scale, may hold the key to the development of novel materials for implant dentistry.

Researchers are currently exploring a scientific solution to unreliable and costly restorative materials used in dentistry.

Fernando Luis Esteban Florez, DDS, Ph.D., MS, an assistant professor at the University of Oklahoma Health Sciences Center, College of Dentistry is currently conducting research at the High Flux Isotope Reactor (HFIR) at the Department of Energy’s Oak Ridge National Laboratory in the hopes of developing a new, more durable, and cheaper material for dental restorations.

Biomaterials currently used in the field have limitations, according to Esteban Florez. These new materials will be designed to bond more tightly to the enamel structure, but also repel the bacteria.

“In fact, the replacement of failed restorations accounts for 70 percent of dentists’ chair time at a yearly cost of $298 billion worldwide,” said Esteban Florez. “Our focus is to create smart restorative dental biomaterials that are less expensive and do not need to be replaced every five to seven years.”

Neutron scattering research, which is a frequently used method in modern science that is used to understand material properties on an atomic scale, may hold the key to the development of novel materials for implant dentistry, Esteban Florez said.

“A dental implant can cost as much as $4,500 per tooth. And that doesn’t include the cost of repairs should the procedure fail; therefore, developing biocompatible polymer- or ceramic-based materials to replace those metals could greatly benefit patients,” he said. “Creating novel materials that are more biocompatible with the human body would be a great asset to dentistry, and neutrons may be the perfect tool for assessing potential materials for this purpose.” 

Neutron scattering has been used to advance many areas of science, including clean energy and the environment, pharmaceuticals, healthcare, and IT. 

Esteban Florez has already performed neutron scattering experiments at Oak Ridge National Laboratory to explore the surface-modification and functionalization of metal oxide nanoparticles in experimental dental adhesive resins. The nanoparticles have long-term antibacterial and bioactive properties. Now, he wants to see if neutron scattering can help him better understand exactly how different restorative materials interact with enamel, dentin, and collagen within teeth. 

Esteban Florez is using the IMAGING instrument at HFIR to study a small collection of human teeth that had been restored either with a dental amalgam or a resin composite. These materials were bound to the sample tooth structures using his experimental dental adhesive resins, which contain varying concentrations of metal oxide nanoparticles.

“Neutron tomography is a powerful technique for exploring the internal aspects of organic materials such as biological tissues. These samples contain a great deal of hydrogen; and since neutrons are particularly sensitive to hydrogen, we can generate very detailed images of their microstructures,” said Dr. Hassina Bilheux, senior neutron imaging scientist at HFIR. 

Dr. Bilheux will work to reconstruct Esteban Florez’s data into three-dimensional renderings that he can use to observe the interactions between restorative dental biomaterials and tooth structures. 

“Neutrons can be used to probe structures within organic tissues in a nondestructive way and allow me to understand how restorative dental biomaterials interact with the entire tooth system,” said Esteban Florez.

The research is focused on the development of polymer-based restorative materials with non-leaching and long-term antibacterial and bioactive properties that can be enhanced using visible light irradiation, he added. Once fully developed, these materials have the potential to kill penetrating bacteria, naturally bond to organic and inorganic components of teeth, and guide the growth of hydroxyapatite to seal the tooth/biomaterial interface.

If this research is successful, these new materials could increase the durability of current polymer-based restorative materials while decreasing the costs of oral healthcare.

“There’s still a great deal of research to be done on this topic, but we’re hopeful that our work will have a significant and positive impact on the field of restorative dentistry,” Esteban Florez said.

For more information, visit the Oak Ridge National Laboratory website.