Your teeth are made up principally of two layers: a dentine layer, which forms the bulk of the tooth, and enamel, a harder outer shell. Over time, enamel can be stained by consuming certain food and drink, and also by smoking.
When we whiten your teeth, we use a specially formulated gentle dental bleaching material which breaks down these stains using a regular oxidation reaction. The bleaching gel is held against your tooth using a custom-made whitening tray.
This tray is carefully crafted to ensure that it fits microscopically around the edges of your teeth to prevent the whitening gel from touching your delicate gum.
If the bleaching gel touches your gum for too long, then it can cause irritation.
This is why we always recommend having your teeth whitening done by a qualified dental professional.