What should I know about tooth bleaching?

Tooth bleaching is one option for whitening your smile. You should discuss your tooth bleaching options with your dentist. He or she can tell you whether the whitening procedure will be effective for you. If you are a candidate for tooth bleaching, some options are:
  • In-office bleaching. This procedure is called chairside bleaching and usually requires only one office visit. The dentist will apply either a protective gel to your gums or a rubber shield to protect the oral soft tissues. A bleaching agent is then applied to the teeth, and a special light may be used. Lasers have been used during tooth whitening procedures to enhance the action of the whitening agent.
  • At-home bleaching. Peroxide-containing whiteners actually bleach the tooth enamel. They typically come in a gel and are placed in a mouthguard. Usage regimens vary. There are potential side effects, such as increased sensitivity or gum irritation. Speak with your dentist if you have any concerns.
Remember when selecting a whitener or any dental product, be sure to look for the ADA Seal of Acceptance -- your assurance that they have met ADA standards of safety and effectiveness.
Tooth bleaching is a fast and convenient way to whiten your teeth for most patients. Before starting your treatment, make sure your dentist does a complete exam including x-rays first. Certain types of tooth stains, dental fillings, and crowns will not lighten with bleaching. Also, if you have receding gums, you may not be a good candidate for bleaching either due to tooth sensitivity. Before you start your tooth bleaching, ask your dentist if you should be placed on a pretreatment prescription fluoride toothpaste or mouthrinse to minimize sensitive teeth.

There are two different types of bleaching systems. One is done in the dental office. This in office treatment can lighten your teeth several shades and is usually completed in two hours. The other treatment involves wearing custom mouth bleaching trays at home. The at home treatment usually takes 2-4 weeks to reach the desired tooth whiteness.

Both treatments are safe to use as directed. The most common side effect is tooth sensitivity which usually goes away quickly once treatment is completed. The results of bleaching usually last weeks to months before another bleaching touchup is needed to maintain the desired tooth lightness. The biggest factors affecting how long your teeth will stay white following your bleaching are habits you may have such as smoking, coffee, tea, and drinking red wines or sauces.

Ask your dentist if you may be a candidate for tooth bleaching.

You should have a dental exam and x-rays by a dentist before whitening your teeth. Any decay in your teeth can be made worse with whitening. The chemicals in the whitening can cause teeth with cavities to abscess leading to pain and the possible loss of a tooth. The chemicals in the whitening can also make the teeth sensitive and the gums sore. Bleaching too much can cause the teeth to become translucent and have a gray color. Ideally, whitening should be prescribed by a dentist, and the whitening process monitored and followed by a dentist to avoid any problems.

Prior to bleaching your teeth it is essential to have a thorough oral examination (with radiographs) to evaluate fillings and other restorations, areas of potential sensitivity such as where recession of the gum is present, and the overall health of your gums. Your gums should be healthy and restorations should be intact prior to considering lightening your teeth.

It is also important to determine the anticipated results in order to decide if bleaching/lightening of the teeth is the proper treatment for you. Many people expect miraculous results without realizing that usually the teeth will be lighter and brighter, but a lighter brighter version of the existing shade. Bleaching, while conservative, will not necesarily achieve the same result as crowns or veneers. Also bleaching will not lighten fillings, so some fillings or other restorations may have to be changed to now match the lighter teeth.

While bleaching treatment results can last quite a while, the teeth are still affected by smoking, food and drink.  Therefore, lifestyle changes may have to be made to keep the teeth light and bright.  Also, even without restaining or darkening of the teeth, you may have to periodically touch up the teeth with a few days of bleaching, usually after a cleaning.

As with any dental treatment, lightening is not to be taken lightly.
Dan Jenkins
You should know whether you have any cavities or exposed nerves on your roots -- the bleaching could cause you pain. You can find this out with a dental examination. You should know that the speed at which the teeth whiten will vary with each person. You should know that once you stop the bleaching your teeth will darken slightly to what they were about two days before. You should also know that the amount of whitening you get is dependent upon how many times you use the bleaching solution and so if you skip some days that is will just take a little longer. You may wish you bleach every other day if you find you have sensitivity with bleaching every night. You should know that the social standard now is not to have the snow white teeth as was popular just a few years ago -- don't overdo it!
Tooth bleaching or whitening means any process that will result in whiter teeth. Before you have your teeth bleached, it's important to know the following facts:
  • Whitening products can include bleach that changes the natural color of your teeth.
  • Whitening products may contain peroxide that removes deep stains and surface discolorations.
  • Non-bleaching products work by eliminating surface stains from the teeth.
  • Teeth whitening can be done at the dentist office or at home with over-the-counter (OTC) teeth whiteners. 
  • Teeth whitening will not change the shade of crowns, dentures, or bridges.
According to the American Dental Association (ADA), you should only use a bleaching product after you have consulted with a dentist. The dentist will perform a complete oral exam to determine if you will benefit from teeth whitening. The dentist might recommend the type of teeth whitener that is best suited for you. If you choose to use a whitening toothpaste at home, make sure the paste has an ADA Seal of Acceptance and contains only polishing agents, and no bleaches.
Regardless of the type of bleach used, some general facts apply:
  • All bleaching systems whiten your teeth, but when bleaching is over, the color will fade about half a shade.
  • Bleaching can only be performed on clean, healthy teeth and healthy gums.
  • Bleaching will not whiten existing fillings and crowns. The doctor must discuss with the patient their expectations and point out what work might need to be changed to achieve consistent color.
  • Bleaching only works on enamel. Teeth which have thin enamel due to chemical or physical abrasion will whiten poorly. This should also be reviewed prior to starting treatment.
  • Sensitive teeth are the most commonly reported side effect.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.