Dark teeth can come from several causes. Sometimes they just have more natural pigment. Or they can be stained from years of tobacco use, coffee drinking, or other substances. The worst cases come from tetracycline stains.
Tooth whitening works for some of these situations. But in cases of tetracycline stains, in particular, tooth whitening will not have a great effect, and porcelain veneers may be required to cover up the dark color.
If your teeth are especially dark, I would strongly recommend that you be very careful in selecting a cosmetic dentist to treat your case. I have received many e-mails from people who had their family dentist, or another dentist who wasn’t really passionate about creating beautiful smiles, treat them, and they were extremely disappointed with the results. In my practice I had to re-do some of these cases. Dentists tend to make one of two mistakes. Either they cover them with porcelain that is too translucent, and the dark color shows through, or they use porcelain that is too opaque and the teeth look pasty and artificial.
Below is a case of dark teeth treated by one of the expert cosmetic dentists in our referral network, Dr. Sam Sadati of West Palm Beach, Florida.