If you decide on tooth whitening, it's best done under the guidelines of a dentist who can help you determine the best method for you, Dr. Levine says. Over-the-counter whiteners are effective, but make sure to use a strip or paint-on system and read the directions carefully.

Some tooth stains are intrinsic—they are created internally by genetics, Dr. Levine says. These stains need a true whitener, done in a dentist's office. Extrinsic tooth stains, which can be created by smoking and consuming things like coffee, red wine and soy sauce, benefit from a good cleaning and an over-the-counter whitener. Good brushing and flossing habits will prevent most of these stains.

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