When it comes to teeth whitening, it’s important for you to understand the causes behind discoloration or staining so you and your dentist can choose the whitening treatment that will provide the best results.

What causes tooth discoloration and staining?

There are a lot of reasons why teeth are not as white as we would like them to be. One factor is simply heredity.

Everyone’s dentin (the layer of your teeth below the enamel) is a unique shade of either yellow or blue/grey. This is normal and varies from person to person. The thickness of a person’s enamel—based on genetics—affects how much of this natural yellow or blue/grey dentin shows through. As people age, the enamel also thins, showing more of the dentin.

Other factors that add to discoloration or staining are:

• Food and beverages, such as wine, coffee, and tea
• Medication such as tetracycline
• Tobacco use
• Trauma to the tooth

Can all stains be whitened, and how long does it take?

The great news is that, yes, most stains—even those caused by medication—can be dramatically improved. However, different stains require different treatment times.

The natural yellow and blue/grey tooth shades will whiten faster than a tooth with added stains from medication, tobacco, and food. Teeth with a natural yellow shade will generally whiten in about 1–2 weeks, whereas teeth with a blue/grey shade can take twice as long. Teeth that have been stained by tobacco use can generally take 1–3 months to whiten, and teeth that have been stained by medications can take anywhere from 2–6 months, based on how severe the staining is. Non-vital, or dead, teeth will respond to whitening well; however, it is important to talk to your dentist about whitening non-vital teeth, as this should be done before whitening the rest of the teeth in order to avoid a difference in shade.