If you have teeth whitening you will need to make several visits to the dental surgery over a couple of months.
The dentist will take an impression of your teeth to make a mouthguard and will instruct you how to use it with a bleaching gel. Then, using your mouthguard at home, you regularly apply the gel for a specified period of time over two to four weeks. Some whitening gels can be left on for up to eight hours at a time, which shortens the treatment period to one week.
Another type of teeth whitening system that a dentist can provide is called laser whitening, which is also known as power whitening. This is where a bleaching product is painted onto your teeth and then a light or laser is shone on them to activate the whitening. Laser whitening takes about an hour.