Teeth can also become stained by bacterial pigments, foodstuffs and tobacco. Oxidizing agents such as hydrogen peroxide or carbamide peroxide are used to lighten the shade of the tooth.
It involves applying bleaching gel to the teeth using thin guard trays. It is generally performed at home for as long as several hours a day for a period of 5 to 14 days. The bleaching agent is low-concentration so irritation to the soft tissue around teeth is minimized.
It utilizes high-concentration bleaching in the dental office. Oxidizing agent is applied to the teeth after a light-cured protective layer is carefully painted on the gums. Power or light-accelerated bleaching, sometimes colloquially referred to as laser bleaching, uses light energy to accelerate the process of bleaching in a dental office.
The effects of bleaching can last for several months depending on the lifestyle of the patient. Factors that decrease whitening include smoking and dark colored liquids like coffee, tea and red wine.