How to whiten teeth

How does Teeth Whitening Work?

Even if we use the term teeth whitening indifferently from teeth bleaching, it is important to know that there is a difference between the two. Teeth whitening actually lightens stains to help restore teeth to their natural color, which can be light yellowish to grey. Teeth bleaching whitens teeth beyond their natural color.

The purpose of teeth whitening is to get the whitening agents below the enamel where the stains have set in. Surface-only cleaners are good for cleaning away day-to-day stains, but different whitening methods will be needed to remove deeper stains; similar to what’s necessary to address laundry stains. The hydroxylapatite crystal rod matrix of enamel is similar to the interweaving of fabric. The deeper the stain, the deeper you have to go with the cleaner to lift the stain away. Some stains never completely come out.

The key to effective teeth whitening is a chemical reaction called “oxidation” initiated by the active ingredient in the whitening product that breaks down the stain. The two most commonly used whitening agents are carbamide peroxide and hydrogen peroxide. The major difference between the two is a matter of potency. Hydrogen peroxide is about 3x more potent than carbamide peroxide so its concentration will often be a third of what’s in a carbamide-based product. In reality, they are the same, but in a different form. When carbamide peroxide comes in contact with saliva, it breaks down into hydrogen peroxide and urea. The oxidation reaction can then take place and whiten the tooth. Why not use hydrogen peroxide in the first place, you may ask? The reason is that carbamide peroxide is much more stable and has a longer shelf life.

Technically speaking, teeth whitening products don’t actually remove stains. The peroxide (and other whitening or bleaching agents) breaks down the larger pigmented molecules of the stains into smaller molecules. With tooth stains broken up, the tooth appears whiter and brighter because more light is reflected off the whiter part of the tooth. This is known as a “whitening effect.”

Chlorine dioxide is another bleaching agent that is usually not used by dentists, but is commonly used by spas and cruise ships who offer teeth whitening treatments to clients and passengers. Most dentists don’t use these products because it can weaken the enamel over time. In fact, such products are banned from being used in dentist offices in the UK.

Blue covarine is an ingredient usually added to non-peroxide products that has shown to be effective in improving the whiteness of a person’s smile. It has been shown to effectively whiten teeth virtually immediately. It does this by adhering to the surface of your teeth and reflecting light more effectively. The result is that your teeth appear whiter.