Whitening toothpaste can appear to whiten teeth slightly by removing surface stains, such as those caused by drinking coffee or smoking. However, whitening toothpastes can't change the natural color of your teeth or lighten a stain that goes deeper than a tooth's surface.

To remove surface stains, whitening toothpaste typically includes:

• Special abrasives that gently polish the teeth
• Peroxide or other chemicals that help break down or dissolve stains

Some whitening toothpastes contain the chemical blue covarine, which adheres to the surface of the teeth and creates an optical illusion that can make teeth appear less yellow.

When used twice a day, whitening toothpaste can take from two to six weeks to make teeth appear whiter. Whitening toothpastes that contain blue covarine can have an immediate effect. Although whitening toothpastes are typically designed to maximize cleaning and minimize wear on tooth enamel, be careful to follow manufacturer recommendations.

If you're considering using a whitening toothpaste, look for a brand that has a seal of approval from a reputable dental organization — such as the American Dental Association Seal of Acceptance. This seal indicates that the toothpaste is safe and effective at removing surface stains.

If you're not satisfied with the effect of whitening toothpaste, ask your dentist or dental hygienist about other tooth-whitening options — such as over-the-counter or professional bleaching products. Results from these products are more predictable because they stay in contact with the tooth surface longer. These products are more expensive, but the extra cost may be worth it if you want better results than are achieved with whitening toothpastes. Some of these products can make your teeth sensitive, but this symptom is reversed by stopping use.