What is tooth whitening?

Tooth whitening is the process of whitening or bleaching teeth generally for adults. Over time, an adult’s teeth become darker as they became stained with foods or bacterial pigments or as the structure of teeth become less porous. Whitening teeth is done either expertly at a dental office or by different use at home tooth whitening and tooth bleaching products.

Whiteness of teeth is usually defined on a scale of 16 shades with tooth whitening generally showing an improvement of anywhere from 2 to 7 shades of whiteness. In general, the tooth whitening procedures at a dentist’s office will be more effective in terms of number of shades of tooth whitening improvement as well as duration of the changes.

Usually, the effects of tooth whitening will last for several months, but may be of a shorter duration and effectiveness if the person smokes or frequently has dark colored foods and drinks such as red wine, tea, and coffee.

Why is tooth whitening needed?

Teeth color darkens due to many different factors. One is changes in the mineral structure of teeth reducing the porousness of tooth enamel. Teeth also becomes stained with different foods, bacterial pigments, and dark colored drinks such as red wine, coffee, and tea. Smoking is another major cause of teeth staining. Some antibiotic medications including tetracycline can also stain teeth or reduce the tooth enamel’s brilliance.

What are the common methods for whitening teeth?

There are many different options for whitening teeth. The first group is from a general dentist or cosmetic dentist’s office. These in-office bleaching methods is usually done with some sort of power or light bleaching known as laser bleaching along with a high concentration tooth whitening gel. Using these lights increases the acceleration of bleaching through halogen plasma arc, or LED lights. These dental teeth whitening procedures usually last about thirty minutes to one hour.

There are also many tooth whitening products for use at home. These include tooth whitening and tooth bleaching gels, pastes, toothpastes, rinse, chewing gums, and strips. These products usually use a low concentration of an oxidizing agent. The typical procedure for tooth whitening usually involves applying the gel to a mouthguard or application try and using it for 15 to 20 minutes, or applying whitening strips or brushing on the gel to your teeth for a short period of time.

Before using any off the shelf whitening teeth products at home, it is recommended that individuals get their teeth and gums checked out by a dentist. The dentist will check your dental and medical history as well as check over your soft tissues, gums, and teeth as well as the status and conditions of any dental implants or restorations to make sure that your tooth whitening procedures will be of minimal risk.

The tooth bleaching and tooth whitening products typically include peroxide which bleaches the enamel to whiten the color of teeth. This peroxide in over the counter tooth whitening products is typically in the form of carbamide peroxide in low concentrations (10% to 44%) to avoid toxicity. This requires that the tooth whitening and tooth bleaching products are used over several weeks to be effective. Currently under development are tooth whitening agents and products that will remineralize the teeth as they whiten them.

Some tooth whitening toothpastes contain different physical and chemical components to help with stains on teeth. These may include aluminum oxide, calcium phosphate, calcium carbonate, and silica and work to grind or rub off stains that may have been left on teeth usually from foods. Thus, toothpastes that purport themselves to have teeth whitening function actually do not intrinsically alter the color of the teeth upon use, although some of the grinding of the teeth with various substances may help with the overall dark appearance of teeth.

I recently heard about something called internal bleaching of teeth. What is that exactly and it is related to teeth whitening or teeth bleaching?

When someone undergoes a root canal otherwise known as an endodontic procedure or therapy, there is a risk of teeth becoming darker and discolored from internal staining of tooth due to fluids or teeth leaching into the inside of the tooth. When this occurs resulting in darkened teeth, a helpful procedure to help with this is internal bleaching. With internal bleaching, a hole is drilled to the pul chamber after which the root canal is cleaned, sealed, and filled with a rubbery substance. After this, peroxide gel is place inside the pulp chamber so that the gel works from inside the tooth on the dentin layer. This peroxide is sealed inside over days and replaced as necessary in a technique called “walking bleach.”

What are the risks for teeth bleaching and tooth whitening?

There are three major risks and side effects from tooth whitening and tooth bleaching:

• chemical burns and tooth sensitivity
• overbleaching or hyperodonto-oxidation
• rebound versus the whitening effect

Since tooth whitening and tooth bleaching require the use of oxidizing agents such as hydrogen peroxide, there comes the risk of chemical burns if the substance is too high of concentration or it is used on unprotected tissues. The most commonly reported side effect with tooth whitening is an increase in tooth sensitivity and irritation of the gums or other soft tissue in the mouth. Most of the time, irritation or sensitivity resulting from tooth bleaching is due to ill fitting mouthguards and mouthpieces rather than an excessive concentration of the bleaching agent. Tooth sensitivity and gum irritation usually are only temporary and last about one to three days after stopping the tooth whitening process.

It has been shown that there is a rebound effect against the tooth whitening process. It has been reported that in some cases nearly half of the tooth whitening and tooth bleaching benefits to have passed within seven days. Whitening rebound is most common in tooth whitening procedures that are intensive treatments (such as those in from dentists and cosmetic dentists).

People that should proceed cautiously include people with sensitive gums, sensitive teeth, defective dental restorations, or receding gums; these people should have consultations with their dentists prior to doing any teeth bleaching or teeth whitening whether at the dentist, with a cosmetic dentist, or at home with kits. Others that should be careful include people with sensitivity to hydrogen peroxide which is the primary tooth whitening and tooth bleaching agent. Tooth whitening and tooth bleaching are not recommended for children under the age of 16 (due to enlarged tooth nerves in childhood which could result in tooth sensitivity) and women who are pregnant or lactation.

An oft discussed issue of tooth bleaching is concerns over the tooth whitening process reducing the thickness of tooth enamel which can lead to other problems. Long terms studies on the subject have shown, however, that just enamel loss is actually insignificant and unlikely to cause any problems.

Also, in cases where the teeth has been with used with bonding or some tooth-colored filling, tooth whitening does not work. In these cases, the recommended course to look into are dental bonding and porcelain veneers as an alternative to tooth bleaching and tooth whitening.

i am interested in whitening my teeth since they have become darker over the years. How do i go about choosing the best tooth whitening service or product?

Do your research. There are many good ways to do research to get more information about whitening teeth. You can get some initial information on the internet researching different tooth whitening and tooth bleaching services and products. A good place to start once you want more information is with a general dentist or cosmetic dentist. They can go over in office tooth whitening procedures and options with you as well as recommend some home use tooth bleaching products. You can also ask your friends and family about their experiences and recommendations with different tooth whitening products and services. If you are interested in using an off the shelf tooth whitening product, the American Dental Association ADA publishes a list of recommended and accepted products so you can be sure to stay safe.