Whitening Systems continued...
Tray-Based Tooth Whiteners
Tray-based tooth whitening systems, purchased either over-the-counter or from a dentist, involve filling a mouth guard-like tray with a gel whitening solution -- which contains a peroxide-bleaching agent. The tray is worn for a period of time, generally from a couple of hours a day to every day during the night for up to four weeks and even longer (depending on the degree of discoloration and desired level of whitening).
In-office bleaching provides the quickest way to whiten teeth. With in-office bleaching, the whitening product is applied directly to the teeth. These products can be used in combination with heat, a special light, or a laser. Results are seen in only one, 30- to 60-minute treatment. But to achieve dramatic results, several appointments are usually needed. However, with in-office bleaching, dramatic results can be seen after the first treatment. This type of whitening is also the most expensive approach.
How Long Do Whitening Effects Last?
Teeth whitening is not permanent. People who expose their teeth to foods and beverages that cause staining may see the whiteness start to fade in as little as one month. Those who avoid foods and beverages that stain may be able to wait one year or longer before another whitening treatment or touch-up is needed.
The degree of whiteness will vary from individual to individual depending on the condition of the teeth, the level of staining, and the type of bleaching system used.
At Home vs. Dentist Supervised
Do-it-yourself methods aren't the same as getting your teeth whitened by a professional. You'll want to consider a few important differences.
Strength of bleaching agent. Over-the-counter products and dentist-supervised at-home products usually contain a lower strength bleaching agent, with about a 10% to 22% carbamide peroxide content, which is equivalent to about 3% hydrogen peroxide. In-office, professionally applied tooth whitening products contain hydrogen peroxide in concentrations ranging from 15% to 43%.
Mouthpiece trays. With dentist-supervised at-home bleaching products, your dentist will take an impression of your teeth and make a mouthpiece tray that is customized to exactly fit your teeth. This customization allows for maximum contact between the whitening gel, which is applied to the mouthpiece tray, and the teeth. A custom-made tray also minimizes the gel's contact with gum tissue.