Whitening options for your teeth
 

Depending on the whitening treatment selected, some are performed in the dental office using an in-office whitening system such as laser whitening. These methods lighten teeth instantly.
 

The same results may be obtained more economically through dentist-supervised at-home whitening, but take longer to achieve. Some whitening systems, which bleach your teeth while you sleep, work in 10 to 14 days (or more accurately nights)! Others bleach your teeth from two to four hours a day requiring three to six weeks to complete.
 

Also it's important to know that certain types of stain respond better to different types of whitening materials. In such cases, your dentist may recommend one method over the other.