Strong teeth for beavers are a must (you try cutting down a tree with your incisors!), but how do they keep those chompers healthy and tough without access to fluoride or a toothbrush? A new study out of Northwestern University reports that beavers have natural protection against tooth decay built into the chemical structure of their teeth.
Researchers found that beaver teeth have a high concentration of iron in them. In addition to causing the teeth to be a reddish-brown color, the iron also makes the enamel harder and more resistant to acid erosion, even more than teeth treated with fluoride.
Related reading: Dental caries susceptibility and enamel strength linked to... your hair?
The research team studied the enamel of rabbits, mice, rats and beavers, as rodent enamel is surprisingly similar to human enamel. In a series of experiments, they subjected the teeth to acid and took before and after images. While layers of hydroxylapatite “nanowires” make up the core structure of enamel, lead author of the study Professor Derk Joester, discovered that the enamel’s acid resistance was actually controlled by the iron- and magnesium-rich material surrounding the nanowires. These minerals are the ones that support the enamel’s acid resistance and structural properties. With this discovery, Joester and his team are the first to decipher the exact composition and structure of enamel.
“We have made a really big step forward in understanding the composition and structure of enamel – the tooth’s protective outer layer – at the smallest length scales,” said Joester, a professor of materials science and engineering at the McCormick School of Engineering and Applied Science. “The unstructured material, which makes up only a small fraction of enamel, likely plays a role in tooth decay. We found it is the minority ions – the ones that provide diversity – that really make the difference in protection. In regular enamel, it’s magnesium, and in the pigmented enamel of beaver and other rodents, it’s iron.”
Related reading: New research finds human tooth enamel development is linked to weaning
In addition to providing a breakthrough in detailing enamel’s composition and structure, the research could have major implications for preventing and treating tooth decay in humans.
“A beaver’s teeth are chemically different from our teeth, not structurally different,” Joester said. “Biology has shown us a way to improve on our enamel. The strategy of what we call ‘grain boundary engineering’ – focusing on the area surrounding the nanowires – lights the way in which we could improve our current treatment with fluoride.”
The full imaging study was published in the journal Science.
America's ToothFairy Initiative Bridges Dental Care Gap for Vulnerable Children
April 18th 2024America's ToothFairy, a nonprofit organization, aids safety-net dental clinics in providing essential care to children in need, with their recent online auction raising money to support access to dental services for thousands of vulnerable kids.
Episode 31: Dentsply Sirona Implant Announcements
September 30th 2021DPR’s Editorial Director Noah Levine sat down with Gene Dorff, Dentsply Sirona’s group vice president of implants and Dr. Dan Butterman to review several big announcements the company made in the arena of implants during Dentsply Sirona World 2021 in Las Vegas.
Crest Toothpaste Honored as National Historic Chemical Landmark
April 10th 2024The American Chemical Society has designated Crest toothpaste as a National Historic Chemical Landmark, recognizing its introduction in 1955 as a transformative moment in dental care through the incorporation of fluoride chemistry.