July 26, 2006

Whitening claims contain little bite

Drugstore aisles teem with toothpastes claiming to do everything from fighting plaque or curbing tartar to freshening breath or shielding sensitive teeth. But the most prominent claim — whitening teeth — presents something of a gray area. Read the fine print on these products and you’ll discover that most promise to whiten by removing stains, not by lightening the base color of the teeth.

Our tests of 41 toothpastes found no correlation between whitening claims and stain-removing ability. Even the seven toothpastes we tested that contain peroxide — the main bleaching ingredient in whitening strips and professional treatments — lightened or bleached out stains no better, overall, than other toothpastes.

In addition to tests measuring stain removal, we rated our toothpastes on their abrasiveness — the extent to which they scraped away the dentin layer under the enamel and gumline — and their fluoride content. We also checked them for unusual tastes and noted their claims to control plaque or tartar. Only those products bearing the American Dental Assn.’s seal of acceptance have clinical evidence backing such claims. Claims without the seal may or may not be valid. One toothpaste shone above the rest.

Ultrabrite All in One Advanced Whitening doesn’t contain peroxide, but it proved excellent at stain removal — and with only average abrasiveness. Its two closest competitors in stain removal — Colgate Max Fresh and Colgate Luminous, both very good overall — were on the high side of what testers labeled “medium” abrasiveness. Ultrabrite also stood out for its price: At just 28 cents per ounce, it qualifies as a Consumer Reports Best Buy.

If you have special brushing needs beyond cleaning, other products might be beneficial:

• Plaque control. Plaque is a soft, sticky, readily removable substance composed of bacteria and their byproducts that accumulates on teeth. Its removal is determined more by flossing and how you brush than by what toothpaste you use. But if you have excessive plaque, consider Colgate Total Whitening Gel (60 cents per ounce). It was the only toothpaste we tested that’s ADA-accepted for plaque and gingivitis prevention.
• Tartar control. Plaque that hardens over time becomes tartar — what the dentist scrapes off during cleaning. Colgate Tartar Control Whitening Gel (33 cents per ounce) is the highest-rated product we tested that bears the ADA seal for this problem. It’s also very good for stain removal.
• Low abrasion. None of the products we rated lowest for abrasiveness cleaned well. Of those with fairly low abrasiveness that also do a good job of removing stains, Aim Whitening with Baking Soda was the least costly (23 cents per ounce).
• Sensitivity. The toothpastes we tested that were specially formulated for sensitive teeth all contain potassium nitrate, an effective ingredient for reducing tooth discomfort. We recommend Crest Sensitivity Original Formula Maximum Strength (91 cents per ounce) because the ADA seal backs its claims.

Claims by 40 of the 41 toothpastes we rated to contain cavity-fighting fluoride within ADA’s acceptable range were confirmed by our tests. The ADA advises everyone to use a fluoride toothpaste. Some evidence suggests that even adults with healthy teeth can benefit from it.