For example, “whitening” is any process that will make teeth appear whiter. This can be achieved in two ways. A product can bleach the tooth, which means that it actually changes the natural tooth color. Bleaching products contain peroxide(s) that help remove deep (intrinsic) and surface (extrinsic) stains. By contrast, non-bleaching whitening products contain agents that work by physical or chemical action to help remove surface stains only.

Whitening products may be administered by dentists in the dental office, dispensed by dentists for home-use, or purchased over-the-counter (OTC), and can be categorized into two major groups:

• Peroxide-containing whiteners or bleaching agents; and
• Whitening toothpastes (dentifrices)

Peroxide-containing whiteners or bleaching agents

Dentist-dispensed and OTC home-use products
Dentist dispensed and OTC home-use tooth whitening bleaches are eligible for the ADA Seal of Acceptance. The products in this category that currently bear the ADA Seal contain 10 percent carbamide peroxide; however, participation in the program is not limited to products of this concentration or type of bleach. There are many whitening options currently available to consumers both from the dentist as well as from retail outlets. The ADA recommends that if you choose to use a bleaching product you should only do so after consultation with a dentist.

In a water-based solution, carbamide peroxide breaks down into hydrogen peroxide and urea, with hydrogen peroxide being the active bleaching agent. Other ingredients of peroxide-containing tooth whiteners may include glycerin, carbopol, sodium hydroxide and flavoring agents.

Accumulated clinical data on neutral pH, 10 percent carbamide peroxide continue to support both the safety and effectiveness of this kind of tooth-whitening agent. The most commonly observed side effects to hydrogen or carbamide peroxide are tooth sensitivity and occasional irritation of the soft tissues in the mouth (oral mucosa), particularly the gums. Tooth sensitivity often occurs during early stages of bleaching treatment. Tissue irritation, in most cases, results from an ill-fitting tray rather than the tooth-bleaching agents. Both of these conditions usually are temporary and stop after the treatment.

Professionally applied bleach whiteners
There are many professionally applied tooth whitening bleach products. These products use hydrogen peroxide in concentrations ranging from 15 percent to 35 percent and are sometimes used together with a light or laser, which the companies state accelerate or activate the whitening process. Prior to application of professional products, gum tissues are isolated either with a rubber dam or a protective gel. Whereas home-use products are intended for use over a two-to-four week period, the professional procedure is usually completed in about one hour.

As with the 10 percent home-use carbamide peroxide bleach products, the most commonly observed side effects of professionally applied hydrogen peroxide products are temporary tooth sensitivity and occasional irritation of oral tissues. On rare occasions, irreversible tooth damage has been reported. Due to the discontinuation of the professional component of the Seal Program on December 31, 2007, professionally applied bleach whiteners are not eligible for the ADA Seal.

The ADA advises patients to consult with their dentists to determine the most appropriate treatment. This is especially important for patients with many fillings, crowns, and extremely dark stains. A thorough oral examination, performed by a licensed dentist, is essential to determine if bleaching is an appropriate course of treatment. The dentist then supervises the use of bleaching agents within the context of a comprehensive, appropriately sequenced treatment plan.

Whitening toothpastes

Whitening toothpastes (dentifrices) in the ADA Seal of Acceptance program contain polishing or chemical agents, rather than bleaches, to improve tooth appearance by removing surface stains. They do this through gentle polishing, chemical chelation, or some other non-bleaching action. Several whitening toothpastes that are available OTC have received the ADA Seal of Acceptance.

You may want to start by speaking with your dentist. He or she can tell you whether whitening procedures would be effective for you. Whiteners may not correct all types of discoloration. For example, yellow-ish hued teeth will probably bleach well, brownish-colored teeth may bleach less well, and grayish-hued teeth may not bleach well at all. Likewise, bleaching may not enhance your smile if you have had bonding or tooth-colored fillings placed in your front teeth. The whitener will not affect the color of these materials, and they will stand out in your newly whitened smile. In these cases, you may want to investigate other options, like porcelain veneers or dental bonding.

What is in-office bleaching?

If you are a candidate for bleaching, your dentist may suggest a procedure that can be done in his or her office. This procedure is called chairside bleaching and may require more than one office visit. Each visit may take from 30 minutes to one hour.

During chairside bleaching, 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 to enhance the action of the agent. Lasers have been used during tooth whitening procedures to enhance the action of the whitening agent.

What are at-home procedures and products?

There are several types of products available for use at home, which can either be dispensed by your dentist or purchased over-the-counter.

Bleaching solutions. These products contain peroxide(s), which actually bleach the tooth enamel. These products typically rely on percent carbamide peroxide as the bleaching agent, carbamide peroxide comes in several different concentrations (10%, 16%, 22%).

Peroxide-containing whiteners typically come in a gel and are placed in a mouthguard. Usage regimens vary. Some products are used for about twice a day for 2 weeks, and others are intended for overnight use for 1-2 weeks. If you obtain the bleaching solution from your dentist, he or she can make a custom-fitted mouthguard for you that will fit your teeth precisely. Currently, only dentist-dispensed home-use 10% carbamide peroxide tray-applied gels carry the ADA Seal.

You also may want to speak with your dentist should any side effects become bothersome. For example, teeth can become sensitive during the period when you are using the bleaching solution. In many cases, this sensitivity is temporary and should lessen once the treatment is finished. Some people also experience soft tissue irritation—either from a tray that doesn’t fit properly or from solution that may come in contact with the tissues. If you have concerns about such side effects, you should discuss them with your dentist.

Toothpastes. All toothpastes help remove surface stain through the action of mild abrasives. “Whitening” toothpastes in the ADA Seal of Acceptance program have special chemical or polishing agents that provide additional stain removal effectiveness. Unlike bleaches, these ADA Accepted products do not alter the intrinsic color of teeth.

How should I choose a whitening product?

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.

Many people are satisfied with the sparkle they get from brushing twice daily with a fluoride-containing toothpaste, cleaning between their teeth once a day and the regular cleanings at your dentist’s office. If you decide you would like to go beyond this to make your smile look brighter, you should investigate all of your options.

You can take several approaches to whiten your smile:

• In-office bleaching;
• At-home bleaching;
• Whitening toothpastes

Note: Before using any whitening procedure, ADHA recommends that you first be evaluated by an oral health care professional to determine which application and program are best for you.
Why do my teeth have stains and discolorations?
Most stains are caused by age, tobacco, coffee, or tea. Other types of stains can be caused by antibiotics, such as tetracycline; or too much fluoride.
What treatments are used for stained teeth?
Ask your oral health care professional about tooth-whitening options. They include a number of over-the-counter whitening systems, whitening toothpastes, and the latest high-tech option–laser tooth whitening. For maximum whitening, experts agree that peroxide is usually the way to go.

Supervised bleaching procedures that are done in-office and at-home have become among the most popular treatment options. In some cases, the procedure is performed entirely in the office, using a light or heat source to speed up the bleaching process. In other cases, an oral health care professional gets the procedure started during an office visit and then gives you what you need to complete it at home. Still another popular procedure is one that you complete entirely at home.

At-home procedures, sometimes called nightguard vital bleaching, consist of placing a bleaching solution, usually a peroxide mixture, in a tray (nightguard) that has been custom fitted for your mouth by an oral health care professional. The bleaching solutions may vary in potency and may be worn for an hour, or throughout the night. Your oral health care professional can advise you on the appropriate type of application and the length of time needed to whiten your teeth, based on the severity of tooth discoloration and your specific needs.
How effective are bleaching systems?
Bleaching is effective in lightning most stains caused by age, tobacco, coffee, and tea. Based on clinical studies, 96 percent of patients with these kinds of stains experience some lightening effect. Other types of stains, such as those produced by tetracycline use or fluorosis (too much fluoride), respond to bleaching less reliably. And one cosmetic dentist points out that bleaching systems are not fully predictable. If you have a tooth-color filling when your teeth are bleached, the filling will stay yellow—dental restorations do not change color when tooth whitener is applied.

Are there any side effects to tooth bleaching?
In some studies, patients have experienced uncomfortable short-term side effects when having teeth bleached. Hydrogen peroxide can increase temperature sensitivity in the teeth, particularly at higher concentrations, and nightguards often cause gum irritation.

And overzealous use of over-the-counter home bleaching products can wear away tooth enamel, especially with solutions that contain acid. Therefore, bleaching is a procedure best done under the care of an oral health care professional.

Still, the general health risks of bleaching systems are minimal as far as your body is concerned. Applications are controlled so that you don’t swallow hydrogen peroxide.

What’s Available?
While research continues into all types of bleaching systems, tooth bleaching is sure to continue to grow in popularity. Here’s a selection of what’s currently available.

At-home bleaching kits—the most popular whitening option. Mouth trays are usually made in one office visit, and your oral health care professional will provide a whitening brand suitable to your needs. Some trays are worn for an hour, others through the night. Kits range in price from $300 to $500.

Bonding—a composite resin that is molded onto the teeth to change their color and to reshape them. The resin material can stain and chip over time. Bonding can usually be done in one office visit for $300-$700 per tooth.

Porcelain veneers— these shell-like facings can be bonded onto stained teeth. They are used to reshape and/or lengthen teeth as well as to whiten. Veneers require at least two office visits and cost $700 to $1,200 per tooth.

Whitening Toothpastes— While some whitening toothpastes effectively keep the teeth cleaner and, therefore, looking whiter, some are more abrasive than others. The stronger toothpastes rely on abrasion to remove external stains as opposed to actually changing the color of teeth. The key is to study a product’s ingredients, look at your teeth to see if it changes their color, and consult your oral health care professional for customized advice.

Whitening Toothpastes

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 your 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.

Whitening Rinses

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 your dentist, involve filling a mouth guard-like tray with a gel whitening solution — which contains a peroxide-bleaching agent — and wearing the tray for a period of time, generally from a couple 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 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 the most expensive technique.

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.

Three major teeth whitening options are available today. All three rely on varying concentrations of peroxide and varying application times.

In-Office Whitening

Significant color change in a short period of time is the major benefit of in-office whitening. This protocol involves the carefully controlled use of a relatively high-concentration peroxide gel, applied to the teeth by the dentist or trained technician after the gums have been protected with a paint-on rubber dam. Generally, the peroxide remains on the teeth for several 15 to 20 minute intervals that add up to an hour (at most). Those with particularly stubborn staining may be advised to return for one or more additional bleaching sessions, or may be asked to continue with a home-use whitening system.

Professionally Dispensed Take-Home Whitening Kits

Many dentists are of the opinion that professionally dispensed take-home whitening kits can produce the best results over the long haul. Take-home kits incorporate an easy-to-use lower-concentration peroxide gel that remains on the teeth for an hour or longer (sometimes overnight). The lower the peroxide percentage, the longer it may safely remain on the teeth. The gel is applied to the teeth using custom-made bleaching trays that resemble mouth guards.

Over-the-Counter Teeth Whitening

The cheapest and most convenient of the teeth whitening options, over-the-counter bleaching involves the use of a store-bought whitening kit, featuring a bleaching gel with a concentration lower than that of the professionally dispensed take-home whiteners. The gel is applied to the teeth via one-size-fits-all trays, whitening strips or paint-on applicators. In many cases this may only whiten a few of the front teeth unlike custom trays that can whiten the entire smile.

Age: There is a direct correlation between tooth color and age. Over the years, teeth darken as a result of wear and tear and stain accumulation. Teenagers will likely experience immediate, dramatic results from whitening. In the twenties, as the teeth begin to show a yellow cast, teeth-whitening may require a little more effort. By the forties, the yellow gives way to brown and more maintenance may be called for. By the fifties, the teeth have absorbed a host of stubborn stains which can prove difficult (but not impossible) to remove.

Starting color: We are all equipped with an inborn tooth color that ranges from yellow-brownish to greenish-grey, and intensifies over time. Yellow-brown is generally more responsive to bleaching than green-grey.

Translucency and thinness: These are also genetic traits that become more pronounced with age. While all teeth show some translucency, those that are opaque and thick have an advantage: they appear lighter in color, show more sparkle and are responsive to bleaching. Teeth that are thinner and more transparent – most notably the front teeth – have less of the pigment that is necessary for bleaching. According to cosmetic dentists, transparency is the only condition that cannot be corrected by any form of teeth whitening.

Eating habits: The habitual consumption of red wine, coffee, tea, cola, carrots, oranges and other deeply-colored beverages and foods causes considerable staining over the years. In addition, acidic foods such as citrus fruits and vinegar contribute to enamel erosion. As a result, the surface becomes more transparent and more of the yellow-colored dentin shows through.

Smoking habits: Nicotine leaves brownish deposits which slowly soak into the tooth structure and cause intrinsic discoloration.

Drugs / chemicals: Tetracycline usage during tooth formation produces dark grey or brown ribbon stains which are very difficult to remove. Excessive consumption of fluoride causes fluorosis and associated areas of white mottling.

Grinding: Most frequently caused by stress,teeth grinding (gnashing, bruising, etc.) can add to micro-cracking in the teeth and can cause the biting edges to darken.

Trauma: Falls and other injuries can produce sizable cracks in the teeth, which collect large amounts of stains and debris

Intrinsic stains are those that form on the interior of teeth. Intrinsic stains result from trauma, aging, exposure to minerals (like tetracycline) during tooth formation and/or excessive ingestion of fluoride. In the past, it was thought that intrinsic stains were too resistant to be corrected by bleaching. Today, cosmetic dentistry experts believe that even deep-set intrinsic stains can be removed with supervised take-home teeth whitening that is maintained over a matter of months or even a year.