Philadelphia, PA (Scicasts) — The bacteria that live in dental plaque and contribute to tooth decay often resist traditional antimicrobial treatment, as they can "hide" within a sticky biofilm matrix, a glue-like polymer scaffold.
A new strategy conceived by University of Pennsylvania researchers took a more sophisticated approach. Instead of simply applying an antibiotic to the teeth, they took advantage of the pH-sensitive and enzyme-like properties of iron-containing nanoparticles to catalyze the activity of hydrogen peroxide, a commonly used natural antiseptic. The activated hydrogen peroxide produced free radicals that were able to simultaneously degrade the biofilm matrix and kill the bacteria within, significantly reducing plaque and preventing the tooth decay, or cavities, in an animal model.
"Even using a very low concentration of hydrogen peroxide, the process was incredibly effective at disrupting the biofilm," said Hyun (Michel) Koo, a professor in the Penn School of Dental Medicine's Department of Orthodontics and divisions of Pediatric Dentistry and Community and Oral Health and the senior author of the study, which was published in the journal Biomaterials. "Adding nanoparticles increased the efficiency of bacterial killing more than 5,000-fold."
