FOR IMMEDIATE RELEASE
ACS News Service Weekly PressPac: August 03, 2022
Ditching the toothbrush for whiter teeth, fewer cavities (video)
“Fast Cross-Linked Hydrogel as a Green Light-Activated Photocatalyst for Localized Biofilm Disruption and Brush-Free Tooth Whitening”
ACS Applied Materials & Interfaces
The first thing people notice when they meet you is your smile. To be more confident when giving wide-mouthed, eye-crinkling smiles, people want healthy, pearly white teeth. But toothpastes only remove surface stains, and whitening treatments can harm enamel, leading to cavities and discoloration. Now, researchers in ACS Applied Materials & Interfaces report a new hydrogel treatment that breaks apart cavity-forming biofilms and whitens teeth without damaging them. Watch a video of the treatment here.
Daily toothbrushing and flossing are good ways to prevent cavities from forming, according to the American Dental Association. However, these methods don’t effectively whiten teeth. For better whitening, consumers often turn to over-the-counter or professional treatments that combine hydrogen peroxide-containing gels and blue light, producing a chemical reaction that removes stains. This combination removes most of the discoloration, but generates reactive oxygen species that can break down enamel. Previously, Xiaolei Wang, Lan Liao and colleagues modified titanium dioxide nanoparticles for a less destructive tooth-whitening treatment. This method still required high-intensity blue light, which can damage nearby skin and eyes. So, the team wanted to find a material that would be activated by green light — a safer alternative — to both whiten teeth and prevent cavities.
The researchers combined bismuth oxychloride nanoparticles, copper oxide nanoparticles and sodium alginate into a thick mixture. Then, they evenly coated the mixture onto the surface of teeth stuck to a slide and sprayed the concoction with a calcium chloride solution, forming a strongly adhering hydrogel. Next, the team tested the material on teeth that were stained with coffee, tea, blueberry juice and soy sauce and placed in a lab dish. Following treatment with the hydrogel and green light, the teeth got brighter over time, and there was no damage to the enamel. In another set of experiments, the team showed that the treatment killed 94% of bacteria in biofilms. To demonstrate that the treatment could work on teeth in vivo, the team used the new method on mice whose mouths were inoculated with cavity-forming bacteria. The green-light activated hydrogel effectively prevented moderate and deep cavities from forming on the surface of the animals’ teeth. The researchers say their safe, brush-free treatment both effectively prevents cavities and whitens teeth.
The authors acknowledge funding from the National Natural Science Foundation of China, Key Youth Project of Jiangxi Province, Key Research and Development Program of Jiangxi Province, Natural Science Foundation of Jiangxi Province and the Graduate Innovation Special Fund Project of Jiangxi Province.
###
The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, e-books and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.
Registered journalists can subscribe to the ACS journalist news portal on EurekAlert! to access embargoed and public science press releases. For media inquiries, contact newsroom@acs.org.
Note: ACS does not conduct research but publishes and publicizes peer-reviewed scientific studies.
Media Contact
ACS Newsroom
newsroom@acs.org