Most people would like to flash a smile of pearly whites, but over time teeth can become stained by foods, beverages and some medications. Unfortunately, the high levels of hydrogen peroxide in dentists’ bleaching treatments can damage enamel and cause tooth sensitivity and gum irritation. Now, researchers reporting in ACS Applied Materials & Interfaces have developed a gel that, when exposed to near infrared (NIR) light, safely whitens teeth without the burn.

The growing demand for selfie-ready smiles has made tooth whitening one of the most popular dental procedures. Treatments at a dentist’s office are effective, but they use high-concentration hydrogen peroxide (30–40

The researchers made oxygen-deficient titania nanoparticles that catalyzed hydroxyl radical production from hydrogen peroxide. Exposing the nanoparticles to NIR light increased their catalytic activity, allowing them to completely bleach tooth samples stained with orange dye, tea or red dye within 2 hours. Then, the researchers made a gel containing the nanoparticles, a carbomer gel and 12

Source: ACS Appl. Mater. Interfaces