Tooth-whitening has been a cosmetic treatment in dentistry for about twenty years, ever since the products were originally used to treat gum disease. It is available as a home-whitening option, where the patient has custom-made whitening trays to fit their teeth and whitening gel to use at home; or an ‘in-chair’ whitening option, where the patient has their teeth whitened by the dentist in the dental chair. Both procedures are very safe, and offer a non-invasive way of improving one’s smile.