Teeth whitening is done with one of two active ingredients: carbamide peroxide or hydrogen peroxide. Some whitening products contain hydrogen peroxide and others contain carbamide peroxide. Hydrogen peroxide alone is an effective whitening agent. Carbamide peroxide—also an effective whitening agent—contains hydrogen peroxide at a ratio of 1:3. For example, a product with 30% carbamide peroxide has about 10% hydrogen peroxide. Hydrogen peroxide breaks down a lot quicker than carbamide peroxide formulas. Hydrogen peroxide has a very short life and is a lot stronger than carbamide peroxide. Products with carbamide peroxide have a slightly longer shelf life than those with hydrogen peroxide, although when refrigerated, all peroxide products have an increased shelf life. Both hydrogen peroxide and carbamide peroxide produce excellent results
You may want to ask , does one work better than the other?
No! The good news is that hydrogen peroxide and carbamide peroxide both produce the same outstanding results. A study published in Journal of the American Dental Association showed that while carbamide peroxide appeared to produce slightly more dramatic results at first, ultimately products containing equivalent amounts of carbamide peroxide and hydrogen peroxide produced exactly the same results.