This is a subjective question. First, it depends on the cause of your teeth becoming stained and discolored. If you are used to drinking tea, coffee, wine, etc, then it is likely that the whitening effect would not last long. The consumption of such liquids will cause your teeth to discolor again. Smoking can also contribute to this. In case your teeth are genetically stained, you might need a teeth whitening treatment again after a few years. Normally, teeth whitening done by professionals stays effective for 5 to 7 years. One thing that is good about teeth whitening treatments is that very rarely do people return to their original teeth condition before treatment.
Patients who smoke cigarettes or drink heavy quantities of dark, acidic liquids like: coffee, tea, red wine, colas, etc. will have to touch up their teeth more often than people who do not.
