Nanotechnology in toothpaste

Toothpaste may contain up to three different ingredients possibly present in the form of nano-sized particles. Hydroxyapatite and titanium dioxide have been present in toothpastes for many decades to protect or whiten teeth, respectively. Consumers are often unaware that many nanoparticles occur naturally and have been used in cosmetics for many decades without adverse responses. While the use of the third ingredient, nanosilver, is restricted to Asian countries, several popular toothpaste brands do not contain nanoparticles at all.