1. The chemical reactions involved in most teeth whitening processes
The chemical compounds that cause stains are called chromogens, which accumulate in the tooth (intrinsic) or on the tooth (extrinsic). During the teeth whitening process, these staining molecules will go through a chemical process, specifically an oxidation reaction. Teeth whitening uses hydrogen peroxide as an oxidising agent, which can permeate the enamel layer to break down the molecules. After the double bonds of chromogens break down, they will scatter and their own molecules will become smaller. They will appear lighter in colour, giving teeth a brighter and whiter appearance.