The study involved 50 bovine teeth stained with tea, and the results indicated that over time, the hydrogen peroxide mouthwashes significantly increased the whiteness of the teeth. In one study, researchers investigated whether hydrogen peroxide mouthwashes or a 10 percent carbamide peroxide gel could whiten teeth more effectively. In fact, many types of toothpaste and mouthwash in stores already contain this compound. Share on Pinterest Many types of toothpaste and mouthwash contain hydrogen peroxide.
