Collaborators from University of Pennsylvania and Indiana University have tested a ‘”nanozyme” system designed to reduce dental plaque. The technology consists of iron oxide nanoparticles that are applied to tooth enamel before a follow-up rinse of hydrogen peroxide. The nanoparticles act as an “enzyme” to activate the hydrogen peroxide, generating reactive oxygen species and killing bacteria that cause tooth decay. Strikingly, the formulation also contains a marker that turns blue in the presence of reactive oxygen species, highlighting the areas of plaque being treated. The technology could act as a supplementary dental hygiene technique.
Our mouths possess a near ideal environment for bacteria to thrive. Warm and moist, with regular exposure to sugary foodstuffs, the oral environment promotes bacterial growth and biofilm formation. In the context of teeth, biofilms are more commonly known as plaque, and regular brushing is a sure-fire way to remove it. However, for some patients, plaque can accumulate very rapidly, and additional techniques to combat it are required.
One such condition is iron-deficiency anemia, which is linked to severe tooth decay. Coincidentally, the iron nanoparticles investigated by these researchers are an FDA-approved treatment for iron-deficiency anemia, and this latest research shows that they may also help with the dental consequences of that condition.
This study involved volunteers who wore a denture-like device that contained real tooth enamel. The volunteers regularly applied sugar solution to the denture, mimicking the sugary snacks many of us like to consume. They didn’t brush the dentures, but applied the nanoparticle/hydrogen peroxide combination twice a day. The treatment reduced the biofilm formation caused by bacteria such as S. mutans, without adversely affecting other microbial populations in the mouth or causing adverse effects.
“We found that this approach is both precise and effective,” said Hyun Koo, a researcher involved in the study, in a UPenn announcement. “It disrupts biofilms, particularly those formed by Streptococcus mutans, which cause caries, and it also reduced the extent of enamel decay. This is the first study we know of done in a clinical setting that demonstrates the therapeutic value of nanozymes against an infectious disease.”
Study in Nano Letters: Ferumoxytol Nanoparticles Target Biofilms Causing Tooth Decay in the Human Mouth