When you think of mussels, what comes to mind? For most people, it’s probably the seashore or a big bowl of cioppino. But for researchers at the University of California Santa Barbara (UCSB) Marine Institute, mussels also represent a strong bond, and a stronger, better dental filling.
According to Kollbe Ahn, one of the UCSB researchers, mussels get their resilience from something called a byssal thread. The byssal thread is what allows the mussels to flexibly adhere to a variety of different surfaces in a variety of inhospitable conditions. This is called sacrificial bonding, a type of chemical bond that dissipates energy without weakening the adhesion and properties of the material.
Human and animal bones and teeth exhibit properties of sacrificial bonding, but mussels have unique chemical function groups known as catechols, which allow them to attach themselves to wet surfaces like rocks, boats and wood. When used in dental filling composites, adhesives with catecholic coupling agents were found to be 10 times stronger than current resin fillings.
Dr. Stephen Hill of Allen, Texas, says this new type of material could be a big deal for patients who need dental restorations.
"Right now, the resin most dentists use lasts about 10 years before it needs replacing, but that time can be drastically cut in half if the patient eats hard foods or grinds their teeth," says Hill. "In some patients a resin restoration may only make it five years before it needs to be replaced."
According to Ahn and the UCSB team, one of the main benefits to their composite is its ability to blend with the rest of the natural tooth.
"When the resin composite hardens, it can get brittle, which worsens over time," says Hill. "This new material is tough but tender, so to speak. It is hard enough to withstand pressure and grinding, but flexible enough to work with the natural tooth and absorb shock so it doesn’t crack."
The UCSB team hopes to continue perfecting the new compound to make it even stronger, but researchers hope to soon market it for dental fillings, crowns and implants.