Teeth are living tissue and a key component of a healthy body. They play important roles in chewing, speaking and social interaction.
Each tooth consists of a crown, which is the white part of the tooth, and the root, which sits inside the gum and out of view. The outside of the crown is covered with a hard substance called enamel. This substance is harder than bone and protects the softer tissue that makes up the core of the tooth.
Underneath the enamel shell is dentin, a yellowish substance that’s similar to bone, but not as hard as enamel. If you lose enamel to trauma, abrasion or age, from the outside of the tooth, the dentin underneath is then exposed to bacteria and other agents that can cause decay. That decay can lead to cavities and other dental problems.
Society at large values bright, white enamel because it’s typically a marker of youth, health and beauty. As you age, it’s natural for your teeth to turn yellowish or darker – this happens as the enamel naturally wears away over time, revealing more of the dentin below.
Other factors can contribute to the dimming of your smile, from smoking to coffee drinking and taking certain medications. Stains from tea, soda, tobacco or other staining foods and drinks can build up over time, which leads many people to want to try to whiten their smile to restore some of that youthful, healthy look.
These days, there are lots of options available if you’re looking to whiten your teeth.
Who Should Use Whitening Products?
Dr. Angela Evanson, a family dentist in Parker, Colorado, notes that while just about anyone can use over-the-counter whitening products, they aren’t always effective for everyone. “The best candidates for over-the-counter teeth whitening are people who have healthy gums and teeth and those who have minor staining on their teeth. People with more serious staining may not see much of a difference with over-the-counter products and may need to consider a professional teeth-whitening treatment.”
Milwaukee-based dentist Dr. Thomas McCarthy, director of product development for Sporting Smiles, a company that makes custom trays used in teeth whitening, says that while most over-the-counter teeth-whitening products are safe to use, you should stop using them right away if you experience pain or an increase in tooth sensitivity. He adds that you shouldn’t use them if you’re:
- Pregnant. During pregnancy, hormone shifts can cause increased blood flow to the gums, which can lead to swelling and sensitivity. Bleaching agents can further irritate sensitive gums.
- Have gum disease. Bleaching agents can irritate the gums and exacerbate gum disease.
- Have cavities. Bleaching agents can sensitize the teeth, and if you have an open cavity, that can cause pain.
- Have sensitive teeth. Bleaching agents can further sensitize sensitive teeth.
Children should also not use teeth whitening products. “Basically, teeth whitening products are designed for individuals who have healthy teeth and want them a little bit whiter,” McCarthy says.
How to Whiten Your Teeth
Evanson says whiteners “work by bleaching the teeth with a peroxide-based solution.” Hydrogen peroxide is an oxidizing agent that “breaks down the molecules that cause stains on teeth.”
Generally speaking, there are four main approaches to whitening your teeth. The first three are at-home options:
Tooth whitening strips typically contain a peroxide-based solution that’s evenly distributed on the thin, plastic strip. This is applied to the teeth and left in place for a period of time, allowing the solution to permeate the tooth’s surface.
At-home whitening strips are popular because they’re widely available and usually the least expensive option for teeth whitening. They can be effective when used properly. However, there are some potential drawbacks, notes Dr. Mitchell Josephs, a general, cosmetic and implant dentist with more than 30 years in practice in Palm Beach, Florida, warns against using popular at-home whitening strip products for several reasons:
- Whitening strips can cause white ulcers – a kind of chemical burn – on the gums. These sores are typically temporary, but can be painful or irritating until they heal.
- Whitening strips can lead to gum recession (as it can irritate the gums) and cause the teeth to become more sensitive.
- Whitening strips can’t bleach artificial crowns and veneers, so if you have such appliances, you’ll end up with a variety of tooth colors after whitening.
- Whitening strips don’t always work, which can mean wasted money.
- Whitening strips can weaken the enamel shell that protects the tooth, leading to other dental issues later.
While whitening strips can be safe and effective, overuse of such products lead to over-bleaching, which can cause your teeth to look gray. When that happens, “you’ll need $32,000 worth of veneers to fix it,” Josephs says.
Dr. Mahnaz Rashti, a dentist in private practice in Beverly Hills, California, says that “one of the most well-known at-home teeth whitening kits is the Crest 3DWhitestrips Professional Effects Teeth Whitening Kit. While it works well and makes teeth whiter, it may cause sensitivity and oral irritation.” Because of these risks, she recommends that you visit your “dental professional to get cleanings rather than using the whitening products that can cause a lot of damage.”
Dr. Joyce Kahng, a cosmetic and restorative dentist and owner of Orange and Magnolia Dental Studio in Costa Mesa, California, says that “it’s important to follow manufacturer’s instructions. For example, it’s not advised to use more than two boxes of Crest Whitestrips per year.”
There can be some other challenges to using these products, says Whitney DiFoggio, a registered dental hygienist and founder of Teeth Talk Girl, an oral health website providing educational articles and videos. For example, whitening strips don’t always stick properly to your teeth and they “can slide around if you produce excess saliva, making them less effective.”
Gels can be painted onto the teeth using a small brush or, more commonly, the solution is delivered to the teeth via trays that are filled with the gel and fit over the teeth like a mouth guard.
“Custom trays work similarly to white strips, except you have to get them made at your dental office,” DiFoggio says. This means your dental provider will take impressions of your teeth and then create trays that fit your unique smile perfectly. You can take these home and fill them with the gel and then wear them for the prescribed amount of time (often about 30 minutes at a time) to achieve at-home whitening.
DiFoggio says that because these trays are custom-built for your mouth, “it’s really rare to see any cases of burns on the gums. They also tend to really stay and stick on teeth even with saliva-filled mouths, so they’re definitely more user-friendly and neater.
Saliva breaks down whitening gel, notes Dr. David Chen, a dentist in private practice in Long Island City, New York. “Your saliva contains a lot of enzymes which can break down whitening gel when it comes into contact with it.”
Similarly, heat can break down the gel. “There have been a few studies showing the longer the whitening gel is in contact with heat, the more it starts to degrade,” Chen says. “The most effective whitening gels are the ones that have been under constant refrigeration right after manufacturing.”
He adds that the longer the product has been sitting on a store shelf, the less effective it will be. “It’ll still whiten, just not as effectively.” Using a custom tray and gel approach will require a visit with your dentist to get the trays made. As such, this approach generally costs more than whitening strips.
“Toothpaste works in a similar way to gels and strips, but it’s not as concentrated so it takes longer to see results,” Evanson says.
Chen says that most whitening toothpastes work differently from whitening gels and strips. “The vast majority of whitening toothpastes do not contain any whitening gels with the exception of Colgate Optic White. Most toothpastes work via mechanical abrasion where they remove surface plaque and food debris but they won’t oxidize stains that are bonded onto your teeth if it does not contain hydrogen peroxide.”
Abrasive toothpastes, such as those that contain baking soda could actually compound issues with staining, Josephs says. “Baking soda does nothing except scratch up your tooth enamel and dental work causing more staining.”
Josephs, like many other dental professionals, says it’s best to leave tooth whitening to the professionals. “In-office power bleaching is controlled, more effective and always the better and safer option for those seeking whiter teeth.” Such treatments typically involve the use of a gel-based bleaching agent along with an ultraviolet light to activate the solution.
DiFoggio notes that while in-office treatments are the most expensive option – about $1,000 on average, depending on where you live and the specifics of the treatment plan – they’re also the fastest. “You can often get results in as quickly as one hour.”
However, she adds that because the bleaching solution is so concentrated, in-office treatments can result in tooth sensitivity. “Also, a consultation appointment is often required before your whitening appointment can be scheduled.”
OTC Whiteners vs. In-Office Whitening Treatments
Over-the-counter products like Crest Whitestrips are different from the whitening products used during an office visit with a dentist, in several ways, with a big one being how they adhere to the teeth. “A whitening strip only covers a little of the teeth. On the other hand, in an office, the whitening treatment would be more thorough and cover more surface area of the teeth,” Rashti says.
There’s also a question of how quickly you’ll see results. Orthodontist Dr. Kami Hoss, founder of The Super Dentists, a multi-specialty dental practice based in Southern California and author of, “If Your Mouth Could Talk: An In-Depth Guide to Oral Health and Its Impact on Your Entire Life,” notes that “most over-the-counter products used for teeth whitening contain a concentration of peroxide from 3% to 10%, while the whitener that’s used at a dentist’s office is closer to 40%.”
Selecting the Right At-Home Tooth Whitener
If you’re going to use an at-home product, DiFoggio recommends using a “reputable product that has the American Dental Association seal of acceptance. This way, you can ensure they have been tested for safety and effectiveness.”
When selecting a product, she recommends considering how much time and money you’re willing to invest in the project. The least expensive options usually take the longest time to begin working and showing results, while the most expensive options – rapid in-office whitening treatments – take the least amount of time to be effective. “You’re really paying for the amount of time that it takes” to make your teeth whiter, she says.
Even if you have selected an ADA-approved whitening product, DiFoggio says it’s best to talk with your dental provider prior to starting the treatment. This goes for anything from toothpaste and strips to gels. “If you’re prone to sensitivity, your dental provider can give you individualized recommendations to help prevent or minimize sensitivity.”
Keeping Your Teeth Healthy
While it may be aesthetically pleasing to have a super white smile, there’s more to dental health than keeping your teeth bright. “Just because someone has ‘white’ teeth doesn’t mean they have healthy teeth,” DiFoggio says. “It’s more important to focus on dental health first.” This means keeping up with regular visits to the dentist for a professional cleaning and to check for cavities and gum disease.
Most healthy adults without major dental or orthodontal complications are advised to visit their dental professional every six months for a routine cleaning and general exam. If you have gum disease or other oral health issues, you may need to see your provider more frequently.
Once your mouth is healthy, then you can work on whitening your teeth, DiFoggio says. “Teeth respond better to the whitening product when they’re clean – meaning without any plaque or tartar build-up.” So, schedule a professional cleaning before you begin any whitening products. “This way, you’ll set yourself up to achieve the best results and not waste your time and money by whitening the plaque on your teeth instead of whitening the teeth themselves.”