This system uses 10 per cent carbamine peroxide. Our laboratory will make up a custom fit tray that holds the peroxide against the surfaces of the teeth and away from the gums. You apply the gel to the tray and insert it, removing any excess with a tissue. Over an 8 hour period the peroxide gently lifts the stain from inside the teeth and after a week we’ll check the shade of the teeth. You will usually find you get excellent results after 2-3 weeks.