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Teeth whitening is getting cheaper and more accessible, but the more popular it gets, the more money there is to be made, resulting in lots of harmful whitening methods, products, and scams that fool or hurt consumers. Remember, this is a $15B industry and the marketing often doesn’t emphasize the safety information as well.
If you’re considering teeth whitening, this guide is for you. Make sure you know what you’re doing before jumping in. You only get one set of teeth in life and it’s all too easy to damage them permanently.
By the end of this post, you’ll know:
- What’s safe and what’s not when it comes to teeth whitening
- How to spot a whitening scam
- How to get the best whitening results
- The safest way to whiten your teeth
Why Teeth Turn Yellow
There are two types of whitening because there are two main ways that teeth turn yellow.
For everyone, teeth yellowing is a normal part of aging. Our hair turns gray and our teeth turn yellow. It’s the inner part of the tooth called dentin—not the outer enamel—that yellows. As teeth repair themselves, the new dentin is darker, and the enamel is getting thinner due to wear, and things like grinding your teeth or acids from foods you eat can thin enamel earlier, making teeth become yellow sooner. The color of dentin reflects through enamel like a prism, making the tooth look yellow.
Besides aging, teeth turn yellow or gray due to:
- Taking tetracycline before age 10
- Falling on or hitting a tooth
- Too much fluoride (also called fluorosis)
- A rare dental disorder called Amelogenesis Imperfecta (AI) which makes the teeth yellow or brown
- Genetics, which determine the color of your teeth to begin with
- Silver fillings
The outer part of the tooth – enamel – can also get stained when you drink tea, coffee, wine, or smoke tobacco. This is called staining and it does not affect the inner color of the teeth.
How teeth Whitening Works
“Intrinsic” refers to whitening the inner part of the tooth, which soaks up hydrogen peroxide gel (also called whitening gel or bleach) and becomes lighter.
When the inner part of the tooth is whitened, the color that’s reflected through the outer enamel of your teeth is lighter, making them look whiter and brighter—reflecting out through the enamel like a prism.
Contrary to what you might have thought, bleach lightens the inner tissue of the tooth, not the hard, outer enamel.
Removing staining on enamel (the outer part of the tooth) is called extrinsic whitening. The stains left behind by smoking, wine, tea, and coffee are usually easily removed with a polish by your hygienist at a teeth cleaning or with polishing and whitening toothpaste, which we’ll discuss in a bit.
Which Kind Is Right for Me?
It depends on whether your teeth are intrinsically yellow or if you’re just dealing with staining.
If you have extrinsic discoloration (i.e. staining from things like coffee and tea) it can be removed by cleaning the teeth with a professional teeth cleaning. Bleach will not work well on extrinsic discoloration.
If you have intrinsic yellowing, no amount of stain-removing toothpaste can lighten the intrinsic color of the tooth. You’ll need to whiten your teeth using a bleaching gel that is held up against the teeth.
When You May Not Want to Whiten
If you fall into one of these groups, I recommend you talk with your dentist about your unique case, as whitening might not be right for you:
- Your teeth are already very sensitive
- You have GERD or acid erosion on your teeth
- You have gum recession
- Your gums are sensitive
- You have sensitivity to hydrogen peroxide
- You have cavities
- You have white spot decalcifications (early cavity) which will become whiter and more noticeable after whitening
- You are pregnant or breastfeeding
- You’re under age 18
- You have visible plastic fillings or crowns
Main Reasons Teeth Go Yellow
There are times when yellow teeth just run in the family. If your parents typically have yellow teeth then you’re likely going to have the same problem. Outside of white, teeth naturally come in reddish brown, reddish yellow, reddish gray, and gray. The depth of the color ranges.
Teeth start to look yellow after enamel thins out and dentin starts to show through. Dentin is a yellow or brownish-colored material hidden under enamel and it is one of the main reasons that teeth look yellow. Dentin is covered up by thick enamel, but keep in mind that it isn’t always able to cover up stains on the surface of teeth, which is another reason for yellow teeth we’ll get to in a minute.
Teeth will naturally become yellow as you age because enamel wears away because of exposure to the acids in the foods and drinks you eat, not to mention the effort of chewing food. Some teeth taken on a more grayish shade if mixed with a lasting food stain.
Nicotine damages more than just the lungs; it also leaves a yellowish or brownish surface stain on teeth – which is another reason to stop smoking!
Many foods stain teeth. Curry spices, berries, and tomatoes in pasta sauce have pigments that cling to the enamel of teeth and stain them. Even that healthy salad can leave your teeth looking dirty.
Antibiotics such as doxycycline and tetracycline stain teeth during development in the gums. The National Institutes of Health suggest that if these antibiotics are taken during the second half of pregnancy or before children turn eight, it could cause permanently stained teeth that need to be treated with an in-office bleaching.
Certain antihistamines, blood pressure drugs, and antipsychotic medications stain teeth. Have a discussion with your physician about the potential side effects of medications that you are currently taking or may soon start taking.
Everyone knows how good fluoride is for teeth, but don’t forget how bad too much of a good thing can be. Too much fluoride causes a condition known as fluorosis which leaves them brown or yellow. Fluoride toothpaste, fluoridated water, and fluoride tablets and treatments are the main sources of fluoride. If you are worried that you’re getting too much fluoride – and the potential side-effects of such – then discuss the issue with your dentist.
Accidents and physical trauma can crack off tooth enamel and damage the interior of a tooth, causing discoloration that could be an indication of bleeding and the need for professional treatment.
Tooth grinding is a habit that some people have caused by stress, particularly when sleeping. The condition is also known as bruxism and it can be harmful to tooth enamel, weakening it until it cracks and yellows.
What Treatment Options Are There For Whitening Teeth?
Treatment options for whitening teeth can vary depending on the reason and extent of discoloration. These may include:
- Whitening strips
- Avoiding food and beverages known to cause stains
- Using proper brushing and flossing techniques
- Bondings and veneers
- Over-the-counter teeth whitening agents (e.g. Snow Teeth Whitening System)
- In-home whitening agents sold by a dentist
- In-office whitening procedures
How To Avoid Yellow Teeth
Brushing teeth, profession cleaning, and whitening treatments and veneers are the best solutions for avoiding yellow teeth. Brushing teeth thoroughly twice a day is essential for avoiding yellow surface stains. It helps to floss teeth at least once a day too. Deeper and more intrinsic stains can be treated with a visit to the dental hygienist, who is able to clean away the unsightly bacteria and tartar, polishing teeth and cleaning them while you wait in the dental chair.
As far as enamel stains are concerned, prevention will always be better than the cure. With some simple lifestyle changes you can prevent your teeth from being discoloured. Avoid smoking and limit the amount of staining foods and drinks you consume. It helps to rinse out your mouth after consuming these foods and drinks.
With all the different options for whitening teeth, there’s no reason for you to feel embarrassed over the color of your teeth. If you aren’t able to correct the problem from home, then your dentist is sure to give you the guidance you need.
How long will my teeth stay white?
Again, this varies from person to person. Some people whiten once/month, while others once/year. Some people say that anything that can stain a white shirt may stain teeth. So, basically, if you’re not whitening, your darkening.
Sensitivity – We always recommend that our patient brush with a toothpaste for sensitive teeth. This is because sometimes the whitening process can make teeth and even gums feel sensitive, even painful. Using a Sensitive Toothpaste will help reduce the likelihood of sensitivity or reduce it dramatically. This will allow you to perform the treatment for the recommended length of time without interruption or discomfort.
Clean Teeth – We also advise that you have your teeth professionally cleaned before whitening. By doing so, your dental professional will be able to remove some surface staining during the polishing procedure and tartar (calculus) that you already have on your tooth surface. You will ideally like to have the whitening solution contact enamel surface without having to penetrate through hard stone tartar.
Origin – Know where your whitening product comes from and it’s ingredients if your are purchasing your whitening from anywhere other than a dental office or reputable pharmacy. If you are having in-office bleaching anywhere other than a dental office then be aware of the place of manufacture and ingredients. If you are not able to review the product or care provider properly, then research or ask your dentist before starting treatment.
Existing Dental Work – Lastly, some people are disappointed to learn that whitening can only change the shade of existing, natural teeth. Dental restorations, such as crowns, bridges, white fillings and the false teeth on dentures are unaffected by the whitening procedure. If this is the case, you’ll want to speak with your dentist about other treatment options to help brighten your smile.
Have more questions about Teeth Whitening?
Give us a call today at (905) 5 SMILES and our friendly team will be happy to help you!
The Your Smile Dental Care Team(905) 576-4537 Oshawa(416) 783-3533 Toronto