Brushing and flossing are everyday ways to keep your teeth bright, healthy. Still, if you might feel like your smile is lacking some sparkle or is more yellow than it used to be, you’re not alone. When the American Academy of Cosmetic Dentistry asked people what they’d most like to improve about their smile, the most common response was whiter teeth. The American Association of Orthodontists also found that nearly 90% of patients requested tooth whitening.
Why Did My Teeth Change Color?
Over time, your teeth can go from white to not-so-bright for a number of reasons:
Food and Drink Coffee, tea and red wine are some major staining culprits. They all have intense color pigments called chromogens that attach to the tooth enamel (the white, outer part of your teeth).
Tobacco Use Two chemicals found in tobacco create stubborn stains: Tar and nicotine. Tar is naturally dark. Nicotine is colorless, but turns yellowish when exposed to oxygen.
Age Below the enamel (the white, outer part of teeth) is a softer area called dentin. Over time, the outer enamel layer gets thinner with brushing and more of the yellowish dentin shows through.
Trauma If you’ve been hit in the mouth, your tooth may change color because it reacts to an injury by laying down more dentin, which is a darker layer under the enamel.
Medications Tooth darkening can be a side effect of certain antihistamines, antipsychotics and high blood pressure medications. Young children who are exposed to antibiotics like tetracycline and doxycycline when their teeth are forming (either in the womb or as a baby) may have discoloration of their adult teeth later in life. Chemotherapy and head and neck radiation can also darken teeth.
How Does Teeth Whitening Work?
Whitening products contain one of two tooth bleaches (hydrogen peroxide or carbamide peroxide). These bleaches break stains into smaller pieces, which makes the color less concentrated and your teeth brighter.
Does Whitening Work on All Teeth?
No, which is why it’s important to talk to your dentist before deciding to whiten your teeth, as whiteners may not correct all types of discoloration. For example, yellow teeth will probably bleach well, brown teeth may not respond as well and teeth with gray tones may not bleach at all. Whitening will not work on caps, veneers, crowns or fillings. It also won’t be effective if your tooth discoloration is caused by medications or a tooth injury.
What Are My Whitening Options?
Talk to your dentist before starting. If you are a candidate, there are four ways to put the shine back in your smile:
Stain Removal Toothpastes
All toothpastes help remove surface stain through the action of mild abrasives that scrub the teeth. Unlike bleaches, these types of products do not change the color of teeth because they can only remove stains on the surface.
This procedure is called chairside bleaching and usually requires only one office visit. A protective gel or a rubber shield would be applied to your gums to protect your gums. Bleach is then applied to the teeth.
At-Home Bleaching from Your Dentist
Your dentist can provide you with a custom-made tray for at-home whitening. In this case, the dentist will give you instructions on how to place the bleaching solution in the tray and for what length of time. This may be a preferred option if you feel more comfortable whitening in your own home at a slower pace, but still with the guidance of a dentist. Out-of-office bleaching can take anywhere from a few days to a few weeks to see results.
Over-the-Counter Bleaching Products
These include whitening toothpastes or strips available at grocery stores or online. The concentration of the bleaching agent in these products is lower than what your dentist would use in the office. If you are thinking about using an over-the-counter bleaching kit.
Are There Any Side Effects from Teeth Whitening?
Some people who use teeth whiteners may experience tooth sensitivity. That happens when the peroxide in the whitener gets through the enamel to the soft layer of dentin and irritates the nerve of your tooth. In most cases the sensitivity is temporary. You can delay treatment, then try again. Overuse of whiteners can also damage the tooth enamel or gums, so be sure to follow directions and talk to your dentist.
This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to be a substitute for professional advice, diagnosis or treatment. Always seek the advice of your dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.
Brian Y. Kuo DDS FAGD