CHENGDU, China: Researchers at Sichuan University have recently made a gel that could bleach teeth like a conventional tooth whitening gel with trivial damage to the enamel.
The high levels of hydrogen peroxide in conventional bleaching treatments can damage enamel and cause tooth sensitivity and gum irritation. Whereas home bleaching products contain less peroxide, six to twelve per cent, they usually require weeks of treatment and don't work as well.
Thus, Xingyu Hu and colleagues developed a gel that safely whitens teeth without burning when exposed to Near Infra-Red (NIR) light. They produced oxygen-deficient titania (TiO2–x) nanoparticles that catalyzed hydroxyl production from hydrogen peroxide. Exposing these particles to NIR light increased their catalytic activity, which bleach tooth samples stained with orange, tea or red dye within 2 hours of exposure completely. Therefore, they incorporate these nanoparticles into a gel containing carbomer gel and 12% hydrogen peroxide.
They applied it to naturally stained tooth samples and treated them with NIR light for an hour. Surprisingly, the same tooth whitening performance was obtained by a self-produced bleaching gel based on this novel system containing 12 per cent HP as the Opalescence Boost, a tooth bleaching product containing 40 per cent HP.
In addition, the trivial enamel destruction, safe temperature range, and good cytocompatibility of TiO2–x nanoparticles also manifested the safety of this tooth bleaching strategy.
The research 'Photothermal-Enhanced Fenton-like Catalytic Activity of Oxygen-Deficient Nanotitania for Efficient and Safe Tooth Whitening' has recently been published in ACS Applied Materials & Interfaces.