Yellow to White: Why Teeth Discolor and How to Brighten your Smile

Think about a time in recent memory where you’ve met someone and they had a bright, white smile. You probably smiled back just as bright, happy to see them and started off with a great conversation. Teeth are important to keep clean and first impressions are a big deal. Whether in a business setting, public speaking, or romantic, whiter teeth will always show you have confidence and you take well care of yourself. It’s not like the other people are inspecting your mouth for cavities, unless it’s your dentist of course, but generally speaking a white(ish) smile is acceptable.

Maybe you’ve been thinking about your smile and would like it just a shade or two whiter than it is right now.  In this article, we’ll discuss why teeth discolor and what you can do to make your smile brighter.

Table of Contents

What causes Teeth to Discolor?


The appearance of teeth varies from person to person and discolored teeth can be caused for many reasons. Some of them are in your control and some are not. The tooth itself is made up of many different parts and a few, in particular, are primarily responsible for color.

On the outer surface of the tooth is the enamel. This is a thin, protective layer with a white pigmentation and semi-transparent. The enamel is made up of many different minerals, primarily calcium and phosphates, and your enamel is actually the hardest surface in the human body! These two minerals in their natural states are silver-gray and blue, respectively, which are why some people’s smiles are so bright they almost look blue. Naturally, your DNA produces a certain combination of minerals in your enamel which effect the color of your teeth.

The dentin is a much softer, less brittle part of the tooth that is directly below the enamel. Both the primary dentin and the secondary dentin layers are a yellow-brown color and very opaque. Again, DNA plays a big part in the pigmentation of your teeth so naturally, darker dentin would result in darker tooth color. This is called intrinsic discoloration when your body and natural changes cause the color of the tooth.

anatomy of a tooth - enamel, dentin, gingiva, root

By simple deduction, enamel being the top layer and white, dentin the layer below, yellow, the less enamel your teeth have, the more prominent the dentin color will show through, hence teeth will be more yellow. Easy, right?

child smiling after eating cherries

child smiling after eating cherries

Teeth Stain

Stained teeth are often what people think of when referring to “discolored teeth.” Not something natural, but a habit the person has that causes their teeth to change color. Dentist classify this type of discoloration as extrinsic discoloration, meaning the enamel actually changes color because of the pigmentation of a substance. The most common causes of stained teeth are coffee, tea, soda, red wine, fruit like cherries and berries, and also smoking. Each of these causes a pigmentation when in contact with the tooth for long periods of time or repeated use.

Tooth Trauma

“Everyone has a plan until they get punched in the mouth.” Mike Tyson once said this and he’s right! Your teeth had a plan to stay white but maybe you fell off your bike when you were younger or got hit in the face playing sports. This likely caused a dental emergency and some trauma to your teeth. Dental trauma can cause potential nerve damage and internal bleeding where blood may reach the pulp of the tooth, causing discoloration. If the color does not return within a few days or months, the stain will likely remain for the life of the tooth unless cosmetically repaired by a dentist.

How Can You Whiten Your Teeth?

There are many ways to whiten your teeth when you consider preventative treatment, natural methods, and professional procedures. They all have their benefits and drawbacks but when it comes down to it, KEEPING your teeth white is what you really want to do. That is why we recommend beginning with preventative measures and ending with cosmetic procedures after other steps have been taken to whiten your teeth.

Preventative Treatments

Oral Care and New Habits

Regularly cleaning your teeth will help avoid having harmful substances and bacteria on your teeth. The longer sugars, acidic food, coffee, and the like, are allowed to sit in your mouth, the faster they work and the more discolored your teeth become. Brushing, flossing, and taking care of your teeth is really about reducing the wear and tear on your teeth and protecting your enamel.

If you regularly drink a cup of coffee in the morning before you leave for work, brush about 30 minutes AFTER the cup of coffee. Your tooth enamel is slightly weaker after you’ve eaten acidic food so brushing immediately after eating or drinking can actually erode some of the tooth enamel. If you go out for a smoke break, brush your teeth when you come back in. That’ll not only keep your teeth cleaner but help smoke-breath as well.

Brushing teeth more often would be beneficial but removing bad habit completely would be an even bigger step. Stopping smoking and drinking water instead of sugary drinks would go a long way to whiter teeth and a healthier life in general. Here is a quick video of what soda does to your teeth:

Remineralize your Teeth with Fluoride Toothpaste and Mouthwash

Above we get a little anatomy lesson how enamel covers the dentin and is responsible for the color of your teeth. Preventing tooth enamel erosion will keep your teeth stronger and last longer, maintaining your white smile. Enamel cannot be restored by your body as it does not contain any living cells but choosing a toothpaste that contains fluoride, using fluoride-rich mouthwash or getting a fluoride treatment can help. Fluoride strengthens the enamel and protects your teeth from acidic foods.

Protect your Teeth with a Night Guard

Naturally, we grind our teeth together when we are chewing food or sometimes we do this in our sleep. The technical term for this is call bruxism. There are many potential causes of grinding but again, protecting from enamel loss is a step to whiter, healthier teeth, fewer cavities, and a brighter smile. A night guard will protect your teeth as you sleep and reduce the wear and tear on your enamel.

Natural ways to Whiten Teeth

Brushing With Baking Soda

Baking soda is a common ingredient in most toothpastes but by itself has a similar effect. The abrasive properties help scrub away plaque and bacteria, and it also creates an alkaline environment, reducing the growth of bacteria, protecting your mouth even further. This isn’t an overnight treatment but long term use is known to have a whitening effect on teeth.

Hydrogen Peroxide and Apple Cider Vinegar

Both natural products have been known to be great cleaning agents for a very long time. Not surprisingly, they can clean teeth as well. The biggest downside to both of these are the strong concentrations the liquids often come in and diluting them properly for oral use. Both hydrogen peroixde and apple cider vinegar can cause not only harm to your teeth but stomach problems as well if used improperly. This isn’t a method we can recommend but accidentally swallowed. Be extremely cautious and do plenty of research before attempting these methods. We cannot recommend trying them or say at what concentration they are safe. Use at your own risk.

vegetables promote healthy teeth

Eat Less Nuts, Beans, and Grains. Eat More Vegetables, Meat and Dairy

Besides the obvious health benefits, foods high in different nutrients help with the natural repair and restoration of teeth. In a study done by the Weston Price Foundation, phytic acid – found in nuts, beans, and grains – contains enzymes that the body cannot digest properly. Phytic Acid is what’s called an “anti-nutrient” that binds to calcium and the molecule itself has phosphorus in it. Why this is bad for teeth is both calcium and phosphorus need to be absorbed to promote good tooth health, where this molecule is blocking this ability. Reducing the intake of phytic acid is the best way to counter-act this effect.
Vitamins A, C, and D are common in vegetables, meats, and dairy products. These are known to reduce the effects of phytic acid. In the same study by Weston Price, a vitamin D supplement was given to one test group which resulted in significantly less tooth decay than the non-vitamin D group.

Professional Teeth Whitening

Teeth Whitening Strips

Whitening strips are a simple product that can be bought in most stores. They are little plastic strips that place across your teeth that often contain bleach or peroxide to create the whitening effect on your teeth. It is no different than how bleach works for clothes or your hair, you are doing the same to your teeth. Be careful when applying them as to avoid touching them to your gums as the chemicals can damage the soft tissue of your gums.

Depending on the brand you decide to go with, strips are applied for about a half hour then removed or some dissolve with saliva and are not removed. Make sure you use the treatments and follow the directions carefully to avoid any harm to your teeth. Leaving on whitening strips for too long could do more harm than good if used improperly.

Whitening strips are applied to the front of the teeth, while the tooth itself is a 3-D object. The edges of the tooth where the whitening strip does not come in contain may remain darker while the rest of the tooth is lighter, leaving an uneven whitening.
Teeth Whitening strips are not recommended for kids or women who are pregnant because of the chemicals involved.

Teeth Whitening Trays

Whitening trays are very similar to the strips but fit in your mouth similar to a bite guard or Invisalign trays. The trays are typically pre-filled with the appropriate amount of bleaching agent and are worn for a longer period of time than other whitening methods, sometimes hours or overnight depending on the brand (see directions for details). Some whitening trays have gel that the user adds in manually. Be careful not to use too much and as above with the whitening strips, be sure to keep the gel from touching the gums or too high up on the tooth if your gums are receding. The tooth enamel only covers so much of the tooth so exposed parts of the tooth could be damaged if improperly applied.

Professional Bleaching by Your Cosmetic Dentist

Professional whitening (or bleaching) is a non-invasive dental treatment that changes the pigmentation of the natural tooth enamel to enhance the beauty of your smile. Treatment is performed in the dental office and you will see results immediately. To get the specific shade of white you desire, it may require more than one visit with each visit lasting 30 to 60 minutes. A protective covering is placed over the gums while a bleaching solution is applied to the teeth. Using a UV light, the dentist heats the gel which enables the product to work faster and more effectively than without. This allows you to get the best whitening within the given timeframe of your appointment.

Always have a consultation with your dentist before having any type of bleaching completed. Whitening products are specifically made for tooth enamel and to whiten teeth, not fillings, crowns, or other restorations. Speaking with your dentist beforehand can allow them to give you the best advice regarding your specific teeth situation.

Dr. Wyne whitening a patients teeth

Frequently asked questions about Teeth Whitening

Is teeth whitening safe?

Yes, whitening teeth is a safe process when completed properly. There are minor nuances in the treatments but common use will not do any harm to the tooth. Improper use of any product is typically where harm is done.
As noted above, because of the chemical used in these products, it is not recommended for kids and pregnant women.

Are there any side effects to teeth whitening?

Sensitive teeth is the most common side effect of teeth whitening and typically lasts a day or two at most. If the sensitivity persists or you have sensitivity prior to having a whitening treatment, consult your dentist and get their opinion. They may recommend you use the treatments less frequently to allow the tooth to heal before repeating the whitening process.

Are there any other conditions where whitening is not appropriate?

If your teeth have cavities that have been filled, crowns, or veneers, these non-tooth materials will not whiten. Any other restorations can typically be changed out to a different shade to match the newly whitened teeth. This would be at the discretion of the dentist and the severity of the case.

Why do whitening kits have LED lights?

Many over the counter whitening kits have a blue LED light that comes with a gel. The light is used to activate the gel and make it work faster. This is similar to the process used by a dentist but is safer for at-home use due to the use of LED lights rather than a UV light.

Why is a professional treatment better than an at home treatment?

The bleaching gel that dentists use has a higher concentration of whitening agent compared to the home remedies. The dentist also uses a UV light instead of an LED light. UV light is stronger than the LED counterpart but it comes with its own risks. Used by a dental professional who is experienced in teeth whitening, the risks are very minimal as the dentist is well educated in proper application and techniques to effectively whiten teeth.

Dentists also perform a more complete whitening experience, ensuring all angles of your teeth are whitened for consistent color rather than possible uneven coloring from home whitening.

How many treatments will I need to whiten my teeth?

Each patient is a case by case basis. Simply put, the more discolored the teeth are, the more treatments are required. Some patients only need one treatment, other could have six or more whitening treatments over the course of a few months before they are in the shade the patient requests.

How long does a professional teeth whitening last?

Each patient is a case by case basis because patient habits are 100% responsible for how long the treatment will be effective. Over half of patients have results lasting typically 9-12 years that take good care of their teeth, brush, and floss regularly, and get come in for cleanings every 6 months. Treatment can last as low as three years or less if a patient decides to drink coffee and soda regularly, smoke, and take poor care of their teeth. If this is the case, this patient likely isn’t fit for treatment in the first place as their teeth will have many other complications than just needing to be whitened.

Interested in Teeth Whitening? has provided a comprehensive guide about different techniques to whiten your teeth whether you want a professional treatment or want to go the home remedy route.

If you are looking for more information or would like to talk to a professional before getting a treatment, feel free to call us or send us a contact request. Aspen Hill Smiles is your Teeth Whitening Rockville service.


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