Teeth whitening or bleaching is a simple, non-invasive dental treatment to change the color of natural tooth enamel to enhance the beauty of your smile.
Teeth whitening may be accomplished in a dental office or at home. The procedure uses a chemical called peroxide to bleach or whiten the teeth. The concentration of peroxide may vary depending on the type of procedure.
Teeth whitening is not permanent. A touch up maybe needed after a year or so, and more often if you smoke or drink coffee, tea, or red wine.
The tooth has a tough outer crystalline layer called enamel which protects it against chewing forces, trauma, extreme temperatures and chemicals. Over time, tooth enamel gradually erodes becoming more translucent and develops micro cracks. The yellowish hue of the underlying tooth layer called dentin becomes more apparent and stains and debris fill up the micro cracks causing teeth to become discolored or lose their luster.
Every day, a thin coating (pellicle) forms on the enamel and picks up stains. Tooth enamel also contains pores that can hold stains. The most common reasons for teeth to get yellow or stained are: Using tobacco Drinking dark-colored liquids such as coffee, cola, tea and red wine Not taking good care of your teeth Aging makes teeth less bright as the enamel gets thinner and the dentin becomes darker. It is also possible to have stains inside the tooth. These are called intrinsic stains. For example, intrinsic stains can be caused by exposure to too much fluoride as a child while teeth are developing. Other causes include tetracycline antibiotics. They can stain a child's teeth if taken by a mother during the second half of pregnancy or by a child who is 8 years old or younger. Teeth are still developing during these years. Trauma may also darken a tooth. Tooth whitening is most effective on surface (extrinsic) stains.
Teeth whitening may be performed as an office procedure, using a home kit provided by your dentist, or using an over-the-counter product. It is advisable to go for a thorough oral checkup and see what your dentist recommends.
The office procedure is recommended for severe stains and discoloration and uses a high concentration of hydrogen peroxide. As a first step, your dentist will cover your lips and gums, so that they are adequately protected. Then, tooth whitening gel containing hydrogen peroxide is carefully applied on to your teeth. Your teeth are then exposed to a special lamp for a total of 45 minutes in two intervals of 20 - 40 minutes each. The light from the lamp breaks down the hydrogen peroxide in the gel, releasing oxygen which bleaches away any stains. Tooth shade guides are used at the beginning and end of treatment to determine how much whitening is desired or has taken place.
Using a professionally-dispensed home kit from your dentist requires two initial office visits. At the first appointment, impressions will be made of your teeth to fabricate custom, clear plastic trays. At your second appointment, you will try on the trays for proper fit, and adjustments will be made if necessary. At home, the trays are worn with special whitening solution either twice a day for 30 minutes each time, or overnight, for a couple of weeks depending on the degree of staining and desired level of whitening. It is normal to experience tooth sensitivity during the time you are whitening your teeth, but it usually subsides shortly after treatment.
You will receive care instructions for your teeth and trays and be encouraged to visit your dentist regularly to help maintain a beautiful, healthy, white smile.
Over the counter products use low-concentration hydrogen peroxide solutions and are recommended when only mild whitening is desired. They are applied with general-sized trays, paint-on applicators or strips. It is important to carefully follow the given instructions.
To maintain results, your dentist will recommend good oral hygiene practices, staying away from certain foods and dark beverages or using a straw, avoiding smoking and periodic follow-up whitening procedures at home or in the clinic.
Teeth whitening is generally a safe procedure but may carry certain risks including increased sensitivity, gum irritation, and uneven coloring.