To avoid the potential negative effects of teeth whitening, we use a unique ingredient known as FS+. FS+ can effectively whiten discolouration, without compromising tooth health, leaving your smile both brighter and healthier. In addition, the FineSmile FS+ whitening formula also contains key ingredients that have been shown to improve tooth strength and alleviate any pre-existing sensitivity. FS+ is also free of the following; PEG, SLS, Parabens, Phthalates, Alcohol, Carrageenan, Toluene and Triclosan. Some types of teeth whitening can be harmful, and cause permanent damage to teeth depending on the ingredients used. Negative effects are most often seen with the use of hydrogen peroxide, which can be found in many different forms of bleaching, but this is the reason we have chosen to be free of peroxide.