The process of whitening teeth with the aid of a dentist is fairly simple. On a microscopic level our enamel has a very porous surface with tubules that collect stain from the things we eat. To reverse this process, a peroxide gel is used to bleach the teeth, breaking stains in to smaller pieces in a similar way stains are removed from fabrics.
This process results in a whiter tooth color. Yellow teeth tend to whiten particularly well. Teeth with shades that are more brown or grey can prove tougher to whiten. It should also be noted that, once whitened, all teeth will darken again over time and require some touch up whitening from time to time to maintain their lighter color.
The nice thing about whitening is that it is simple to do and each person gets to decide when they have arrived at the color they’re looking for. Consult your dentist for their opinion on the results that can be achieved.