Two Types of Stained Teeth
Teeth whitening is very effective at correcting one kind of tooth staining, but it is completely ineffective for other types of discolored teeth. To know whether teeth whitening is right for you, you have to understand the type of staining you have.
Extrinsic staining occurs when teeth become stained from outside sources. Intrinsic staining occurs when the tooth becomes discolored from within.
The most common causes of extrinsic staining are:
- Red wine
- Dark beer
These stains appear gradually over time. You may remember your teeth being whiter--and have pictures proving it--but now your teeth are discolored. It's also important to note that your teeth can even be stained by light-colored foods and beverages, such as white wine, which is acidic, and allows stains from other sources to penetrate into your teeth.
Intrinsic staining occurs when your teeth becomes discolored from within. Probably the most common cause is tooth trauma, which can essentially cause a tooth to be bruised. It may turn dark brown or black. Sometimes, this is a sign that the tooth has died and needs to be treated with a root canal or pulled, but other times the tooth is still alive. Teeth can also be stained by enamel defects caused while the tooth was forming. In these cases, the tooth will either emerge discolored or get discolored as a result of a specific event. These types of discoloration do not respond to teeth whitening.
An in-between case is tetracycline-related staining. Tetracycline is an antibiotic that, along with other tetracycline side effects, can cause your dentin--the middle layer of your teeth, between the outer enamel and the inner pulp--to become discolored. Your teeth may initially seem yellow, but turn brown over time. This can sometimes be affected by teeth whitening.