Many teeth whitening systems and products are available, including whitening toothpastes, over-the-counter gels, rinses, strips, trays, and whitening products obtained from a dentist.
Teeth whitening is ideal for people who have healthy, unrestored teeth (no fillings) and gums. Individuals with yellow tones to their teeth respond best. But this cosmetic procedure is not recommended for everyone.
Find out if teeth whitening is right for you.
All toothpastes help remove surface stains, because they contain mild abrasives. Some whitening toothpastes contain gentle polishing or chemical agents that provide additional stain removal effectiveness. Whitening toothpastes can help remove surface stains only and do not contain bleach; over-the-counter and professional whitening products contain carbamide peroxide or hydrogen peroxide that helps lighten the color deep in the tooth. Whitening toothpastes can lighten the tooth's color by about one shade. In contrast, light-activated whitening conducted in your dentist's office can make your teeth three to eight shades lighter.
Over-the-Counter Whitening Strips and Gels
Whitening gels are clear, peroxide-based gels applied with a small brush directly to the surface of your teeth. Instructions generally call for twice a day application for 14 days. Initial results are seen in a few days and final results are sustained for about four months.
Whitening strips are very thin, virtually invisible strips that are coated with a peroxide-based whitening gel. The strips are applied twice daily for 30 minutes for 14 days. Initial results are seen in a few days and final results are sustained for about four months.
Among the newest whitening products available are whitening rinses. Like most mouthwashes, they freshen breath and help reduce dental plaque and gum disease. But these products also include ingredients, such as hydrogen peroxide, which whiten teeth. Manufacturers say it may take 12 weeks to see results. You just swish them around in your mouth for 60 seconds twice a day before brushing your teeth. However, some experts say that rinses may not be as effective as other over-the-counter whitening products. Because a whitening rinse is only in contact with the teeth for such a short time -- just two minutes a day compared to 30 minutes for many strips -- it may have less of an effect.
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, and/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 technique.
How Long Do Teeth 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 Teeth Whitening vs. Dentist-Supervised Teeth Whitening
There are differences between whitening teeth at home and having them bleached in a dentist's office, including:
- 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. Over-the-counter whitening products also contain a mouthpiece tray, but the "one-size-fits-all" approach means that the fit will not be exact. Ill-fitting trays can irritate the gum and soft tissue by allowing more bleaching gel to seep onto these tissues. With in-office procedures, the bleaching agent is applied directly to the teeth.
- Additional protective measures. In the office setting, your dentist will apply either a gel to the gum tissue or use a rubber shield (which slides over the teeth) prior to treatment to protect your gums and oral cavities from the effects of the bleaching. Over-the-counter products don't provide these extra protective measures.
- Costs. Over-the-counter bleaching systems are the least expensive option, with in-office whitening being the costliest.
- Supervised vs. unsupervised process. Dentist-supervised at-home bleaching and in-office treatments offer additional benefits compared with over-the-counter procedures. First, your dentist can perform an oral exam and consider your complete medical history, which can be helpful in determining if bleaching is an appropriate course of treatment based on the type and extent of stains, and the number and location of restorations. Your dentist can then better match the type of stain with the best treatment, if appropriate, to lighten those stains. With dentist-supervised bleaching procedures, your dentist will likely want to see you a couple of times to ensure you are following directions, to make sure the customized tray is fitting properly, to inspect the gums for signs of irritation, and to generally check on how the teeth whitening process is proceeding. With over-the-counter bleaching products, you are on your own.
Who Should Not Undergo Teeth Whitening?
Whitening is not recommended or will be less successful in the following circumstances:
- Age and pregnancy issues. Bleaching is not recommended in children under the age of 16. This is because the pulp chamber, or nerve of the tooth, is enlarged until this age. Teeth whitening under this condition could irritate the pulp or cause it to become sensitive. Teeth whitening is also not recommended in pregnant or lactating women.
- Sensitive teeth and allergies. Individuals with sensitive teeth and gums, receding gums, and/or defective restorations should consult with their dentist prior to using a tooth-whitening system. Anyone allergic to peroxide (the whitening agent) should not use a bleaching product.
- Gum disease, worn enamel, cavities, and exposed roots. Individuals with gum disease or teeth with worn enamel are generally discouraged from undergoing a tooth-whitening procedure. Cavities need to be treated before undergoing any whitening procedure. This is because the whitening solutions penetrate into any existing decay and the inner areas of the tooth, which can cause sensitivity. Also, whitening procedures will not work on exposed tooth roots, because roots do not have an enamel layer.
- Fillings, crowns, and other restorations. Tooth-colored fillings and resin composite materials used in dental restorations (crowns, veneers, bonding, bridges) do not whiten. Therefore, using a whitening agent on teeth that contain restorations will result in uneven whitening -- in this case, making the teeth without restorations appear lighter than those with restorations. Any whitening procedure should be done prior to the placement of restorations. Individuals with numerous restorations that would result in uneven whitening may be better off considering bonding, veneers, or crowns rather than a tooth whitening system. Ask your dentist what strategy is best for you.
- Unrealistic expectations. Individuals who expect their teeth to be a new "blinding white" may be disappointed with their results. Smokers need to be aware that their results will be limited unless they refrain from continued smoking, particularly during the bleaching process. A healthy guide to is to achieve a shade slightly whiter than the whites of your eyes.
- Darkly stained teeth. Yellowish teeth respond well to bleaching, brownish-colored teeth respond less well and grayish-hue or purple-stained teeth may not respond to bleaching at all. Blue-gray staining caused by the antibiotic tetracycline is more difficult to lighten and may require up to six months of home treatments or several in-office appointments to successfully lighten. Teeth that have dark stains may be better candidates for another lightening option, such as veneers, bonding, or crowns. Your dentist can discuss the options best suited for you.
Risks Associated With Teeth Whitening
The two side effects that occur most often with teeth whitening are a temporary increase in tooth sensitivity and mild irritation of the soft tissues of the mouth, particularly the gums. Tooth sensitivity often occurs during early stages of the bleaching treatment. Tissue irritation most commonly results from an ill-fitting mouthpiece tray rather than the tooth-bleaching agent. Both of these conditions usually are temporary and disappear within one to three days of stopping or completing treatment.
If you do experience sensitivity, you can reduce or eliminate it by:
- Wearing the tray for a shorter period of time (for example, two 30-minute sessions vs. two 60-minute sessions).
- Stop whitening your teeth for two to three days to allow teeth to adjust to the whitening process.
- Ask your dentist or pharmacist for a high fluoride-containing product, which can help remineralize your teeth. Apply the fluoride product to the tray and wear for four minutes prior to and following the whitening agent.
- Brush teeth with a toothpaste made for sensitive teeth. These toothpastes contain potassium nitrate, which helps soothe the teeth's nerve endings.