Teeth whitening is one of the most popular cosmetic dental procedures today, and the treatment offered at the dentist office is the most effective. But exactly how does it work? Here, we’ll take a look at the science behind those bright white teeth.
Like the skin, teeth have separate layers. The outermost layer is called the enamel. It is made up of a tightly-packed crystal structure called rods, making it very hard. Though it may appear solid and smooth to the naked eye, at a microscopic level, molecules can get in between the rods to cause staining. These stains cannot be removed simply by brushing. Instead, dentists get down to where the stains are by using a chemical that can reach them and break them up.
The chemicals used at a dentist office for teeth whitening procedures are hydrogen peroxide and carbamide peroxide (which breaks down into hydrogen peroxide in the mouth). These chemicals utilize a reaction called oxidation after penetrating the teeth, which causes the stain compounds to break down. This is how in-office treatments differ from over-the-counter whitening solutions like whitening toothpastes: professional treatments penetrate the tooth surface while other methods merely remove surface stains. They do this by being more abrasive than regular toothpastes, which is why dentists may discourage their use.
At-home teeth whitening products do contain carbamide or hydrogen peroxide, but in much lower concentrations. They also contain other ingredients added for flavor and to help reduce tooth sensitivity. These products are cheaper than in-office treatments, but results take longer to see (weeks as opposed to days or minutes).
If you are considering a teeth whitening procedure, it’s recommended that you consult with your dentist first. Not only do they provide the most effective treatment, but they can advise you on whether or not your teeth should undergo the treatment at all. Fixtures such as fillings and crowns cannot be whitened as natural teeth can, and may need an alternative treatment.