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Will Charcoal Toothpaste Whiten Teeth Safely?

Activated charcoal is a natural abrasive so it can whiten your teeth when used in toothpaste but it can only remove extrinsic stains and not intrinsic ones.


crest charcoal deep clean toothpaste

The reason is because there are two types of tooth stains but charcoal will only get rid of the extrinsic ones. This means it is a whitening product but not a bleaching one. In order to be a bleaching one, it needs to also remove intrinsic stains.


Aside from that, the official stance by the American Dental Association (ADA), is that there is insufficient clinical and laboratory data on charcoal toothpaste. They recommend the need for larger scale and better designed studies to test its safety and efficacy. Thus, dental professionals should be cautious when advising patients in using it due to many unproven claims.


Table of contents:


Background on activated charcoal use

The use of activated charcoal has been around for a very long time. Most notably it has been used as a treatment in the emergency room to absorb toxins for patients who may have overdosed.


Nowadays it has been trendy to use it to clean your body not only on the inside but also outside. You can find it in various everyday products.

  • Face washes

  • Face masks

  • Pills

  • Drinks

  • Toothpastes


It can absorb toxins in your gut as well as your skin. That is why you can apply these products directly on your skin and also permit you to drink or consume it as well.


Nonetheless, the one that we're most interested in is its use as a whitening toothpaste. Despite the fact that it is pure black in color, it can allegedly make your teeth whiter if you brush with it. Sounds counterintuitive doesn't it? We're going to explore whether or not that is true.


Does charcoal toothpaste work?

Charcoal toothpaste can whiten teeth since it is a natural abrasive. This means that it can mechanically remove extrinsic stains just like all of the other whitening toothpastes on the market. However it may not be that effective at removing intrinsic tooth stains since it lacks the chemical means to oxidize them.


The reason is because teeth become discolored by accumulating a combination of extrinsic and intrinsic stains. The extrinsic ones are on the surface of the tooth while the intrinsic ones are deeply embedded within it. This makes the intrinsic ones impossible for removal via mechanical means. Only chemical agents can reach the intrinsic stains.


Nonetheless it is still a whitening toothpaste since it possesses an abrasive system. That means it will whiten your teeth if you brush with it. In fact, there was one study in the International Journal of Dental Sciences which found charcoal toothpaste to be a more effective tooth whitener than a peroxide based one. Although that was the only study to find so.


How to use charcoal toothpaste

  1. Rinse your mouth. This is to wet the entire oral cavity and also to remove gross food debris.

  2. Wet your toothbrush. This will help the toothpaste lather.

  3. Apply charcoal toothpaste to toothbrush.

  4. Brush all surfaces of your teeth for at least two minutes.

  5. Rinse out your mouth thoroughly to remove any residue.


Examples of activated charcoal toothpastes:

  • Hello activated charcoal

  • Colgate with activated charcoal

  • Crest 3D white charcoal

  • The natural dentist charcoal whitening


Effective at removing extrinsic stains

Since charcoal is naturally abrasive it can mechanically abrade the extrinsic stains that are on the exterior surface of the tooth. This is done by simply brushing your teeth with it.


Studies have shown that it is the abrasive component of a whitening toothpaste which determines how effective it is at whitening teeth. It is all due to having an abrasive within the toothpaste which permits it to make teeth whiter and that is essentially what a whitening toothpaste is.


Overall, the way charcoal toothpaste whitens is very similar to how baking soda toothpaste works. In a study done in the Journal of the American Dental Association, they found that baking soda removed stains and whitened teeth purely based on its abrasive quality.


Abrasives in other whitening toothpastes

Charcoal and baking soda are just two types of abrasives within whitening toothpastes. Other brands which market their product as whitening can use completely different ingredients to achieve the same result.


Toothpaste


Whitening Abrasive


Relative Dentin Abrasivity (RDA)

Hello activated charcoal

Activated Charcoal

90.67

Colgate Total

Hydrated silicon dioxide

44

Oral B, Colgate whitening, Sensodyne

Hydrated silica

65

Opalesence

Silica

66

Tom's

Calcium carbonate, Sodium bicarbonate, hydrated silica

49

Arm & Hammer

Sodium bicarbonate

8

Pepsodent

Silicon dioxide

50

Clinomyn

Calcium carbonate, Silicon dioxide, Aluminium silicate

124

Apoliva

Silica

70

Acta original

Natriummetafosfat

45-60


This chart utilized data that was mainly from a study in Acta Odontologica Scandinavica. We added in additional info to make it more relevant.


The point that we're trying to make is that there are a lot of abrasives which can be used for whitening. Some toothpastes even utilize a combination of them. Without them the toothpaste wouldn't be able to make your teeth less yellow.


Potential causes of extrinsic stains

As its name implies, extrinsic types of stains are located on the exterior surface of the tooth. Anything that is colored and can remain on or adhere to the enamel is considered staining. If it can color your white t-shirt, it can probably stain your enamel.

  • Coffee

  • Tea

  • Red wine

  • Tobacco or anything with tar in it

  • Pigmented beverages like sodas

  • Pigmented foods like curry and turmeric

  • Unremoved plaque and tartar


The most important point to understand about this type of tooth discoloration is that they occur on the surface of the dentition. That makes them susceptible to mechanical removal by using an abrasive toothpaste along with a toothbrush.


This is certainly a form of whitening but it is not the bleaching kind of whitening.


Ineffective at removing intrinsic stains

Charcoal toothpaste may be effective at removing extrinsic stains but where it falls short is its inability to remove intrinsic stains. Since the intrinsic ones are deeply embedded beneath the surface of the tooth, mechanical brushing will not be able to remove it.


The only way to reach and get rid of stains on the interior of the tooth is with a chemical agent that can oxidize it. The only known substance that is capable of chemically oxidizing intrinsic tooth stains is hydrogen peroxide or a derivative of it. Consequently that is what in-office bleaching treatments use, a high concentration of hydrogen peroxide to whiten teeth.


Since charcoal toothpastes are all natural, they do not contain any hydrogen peroxide within them. This means that they will NOT be able to remove intrinsic stains nor will they be able to change the color of the tooth. It is the hydrogen peroxide whitening which we usually think of as teeth whitening. Although we suppose it is more correct to differentiate it as teeth bleaching rather than whitening.


The peroxide whitening is a chemical reaction that will whiten the tooth. That is vastly different from extrinsic stain removal whitening, which is a mechanical process. The external stain removal by brushing is similar to if you were brushing a stain off the table top. The chemical whitening is similar to bleaching a t-shirt white. That is the difference and we believe you should understand what we mean by that.


How does hydrogen peroxide whiten teeth?

Hydrogen peroxide is a chemical agent that will whiten teeth by bleaching them. It does so by diffusing through the tooth while oxidizing the intrinsic stains which are embedded in the organic matrices. It is potent enough that it can even travel through the dentin and end up at the pulp within 15 minutes of the treatment.


The peroxide will oxidize all of the organic matrices but it will leave the inorganic intact. That is significant because the enamel layer is about 98-99% inorganic with the rest being organic. The dentin on the other hand is about 20% organic. This means that it will whiten the enamel and the dentin, which you may not have realized.


The important point to takeaway here is that intrinsic stains are embedded within the interior of the tooth. That makes it impervious to extrinsic stain removal mechanisms such as by mechanically brushing the tooth. The only way to reach it and get rid of it is by using a chemical bleaching agent such as hydrogen peroxide.


Since charcoal toothpastes consist of only activated charcoal and nothing else, it will lack the ability to chemically oxidize intrinsic stains. It needs to have hydrogen peroxide in order for it to accomplish this.


Causes of intrinsic stains

The intrinsic stains on teeth are quite different from the extrinsic ones because they're located on the interior of the tooth and not exterior. This makes them impervious to mechanical removal via toothpaste abrasives.


The only way to get rid of them is with a chemical agent that can penetrate through the tooth. Otherwise you wouldn't be able to reach nor affect these stains.


Possible causes of intrinsic stains according to the ADA:

  • Genetic or systemic disorders such as amelogenesis imperfecta

  • Fluorosis such as intake of too much fluoride.

  • Aging. Enamel becomes thinner and more translucent which permits the more yellow dentin to show through.

  • Tetracycline use during tooth development.

  • Tooth decay since they're brown to black in color.

  • Amalgam restorations because they can stain surrounding tooth structure.

  • Dead teeth become grey looking.

  • Using chlorhexidine mouth rinse for an extended period of time.

  • Pigmented foods and beverages such as coffee, tea, and red wine.


Charcoal toothpaste whitening safety

It is unclear whether or not charcoal toothpaste is safe to use for whitening. According to the ADA, they recommend that dentists should be cautious when discussing about using it as a toothpaste. This is due to the fact that there hasn't been sufficient studies done on its safety and efficacy as a whitening toothpaste.


Nonetheless it does appear that it can whiten your teeth but not bleach them. However in regards to its safety, we did find quite a few studies which concluded that you should be cautious in using it. Here were some of the adverse side effects from using it as a tooth whitener.

  • Can be potentially very abrasive on the enamel.

  • Can affect the color and gloss of ceramic restorations.

  • Can affect the color and surface roughness of composite fillings.


Potentially very abrasive on the enamel

Regarding the abrasiveness of charcoal toothpaste, the verdict is actually uncertain. Scientific research is providing mixed results with some saying that it is harmful to the enamel while others say that there is no effect.


This particular study found that charcoal toothpaste was more abrasive than other types of whitening toothpastes. The more activated charcoal it had the more abrasive it became. Their conclusion was that due to its higher abrasivity, it is less safe than other toothpastes.


There was also another study about 350 people in two Malaysian villages that used salt and charcoal as a toothpaste. Despite it being a dying practice, that was the only "toothpaste" that was available to them. Unfortunately what the researchers found was that all of their teeth had abrasions on them, which implies that the charcoal may be TOO ABRASIVE.


Both of these studies may not be giving you the best impression of activated charcoal being used in toothpaste but some of the brands in the US are saying otherwise. The Natural Dentist charcoal toothpaste says that their product has only a 76 RDA (relative dentin abrasivity). The Hello charcoal toothpaste says that theirs is a 90.69 RDA.


The significance of that is, they're both still within the acceptable limits for RDA values for toothpastes. It is certainly not a low abrasive toothpaste because those numbers fall in or closer to the medium abrasive category.


Toothpaste RDA chart

RDA values basically tell you how abrasive they can be against the dentin of the tooth. Technically according to the chart above it isn't until 151-250 RDA that it starts to become regarded as "harmful" to the tooth. So theoretically this whitening toothpaste shouldn't be "bad" for you.


Affects color and gloss of veneers and crowns

According to a study in JERD, the abrasiveness of charcoal toothpaste can affect the color and gloss of ceramic restorations. In other words, it is abrasive enough to potentially damage porcelain veneers and porcelain crowns.


The researchers from the study concluded that charcoal toothpaste enhanced the loss of color and gloss from porcelain restorations. That is not good because you don't want to damage the surface and sheen of porcelain veneers! Especially since they're expensive to get in the first place.


The takeaway from this is that if you have veneers in your mouth, you may want to reconsider using activated charcoal to clean your teeth. It would be alot more expensive to replace veneers than simply buying another toothpaste.


Affects color and surface roughness of tooth colored fillings

There has been quite a few studies which have shown that charcoal toothpaste may affect the surface roughness and also the color of the composite fillings.


One study in the journal of Operative Dentistry, found that charcoal toothpastes generally resulted in composite color change. Some of the margins of the tooth colored fillings were stained after using the product. The researchers concluded that the amount of color change in the composites were clinical unacceptable.


Overall, many studies reported that the surface roughness of the teeth were different after using the toothpaste. One study found that the surface roughness increased but the microhardness was unaffected. Another study found that after using the charcoal for 3 months, the surface of the enamel was different!


Even though these reports are saying that the surface roughness of the enamel may be affected, it doesn't mean that it is being eroded away. For it to be classified as erosion, it would need to be a chemically acidic reaction that melts away the enamel. The change in surface texture by using charcoal is a mechanical process so it wouldn't qualify as erosion.


Whitening efficacy of charcoal

Unfortunately charcoal toothpaste is NOT the most effective whitening toothpaste on the market. It has to do with the fact that tooth discoloration is a result of a combination of extrinsic and intrinsic stains.


The abrasive property that charcoal contains does make it effective in removing the extrinsic stains. However it lacks the capability to eliminate intrinsic stains since that requires a chemical bleaching agent such as hydrogen peroxide. It does not contain any peroxide thus rendering it ineffective at getting rid of the intrinsic stains. All of this was verified by a study which concluded that charcoal had no bleaching effect.


A more effective whitening toothpaste would be one that can remove both types of stains such as the colgate optic white. This means you should look for a product that has hydrogen peroxide in the ingredients. Studies have shown that peroxide based toothpastes were superior in whitening.


Examples of whitening toothpastes with peroxide:

  • Colgate optic white pro series

  • Crest 3D white professional

  • Arm and Hammer advanced whitening

  • Supersmile professional whitening


In case you wanted additional validation, a study by BMC Oral Health compared the whitening effects of charcoal with other toothpastes. None of the whitening dentifrices had any perceivable change in color except the Colgate Optic White, which contained hydrogen peroxide! That was the only one with a perceivable change in color.


Is charcoal good for your teeth?

Teeth whitening is an elective cosmetic procedure so even though charcoal toothpaste can whiten it, it isn't a factor for determining if it is good for your teeth. For a product to be good for your teeth, it needs to provide a beneficial result such as making your teeth healthier and stronger.


For an oral health perspective, this would mean that the product should strengthen your teeth, prevent cavities, or even reverse tooth decay. There are literally two ingredients in this world which can accomplish all of those, fluoride and nano-hydroxyapatite.


We strongly believe that a toothpaste needs to be able to reverse and stop cavities in order for it to be considered good for your teeth. Since charcoal toothpaste can't exactly do any of those, we'll have to say that it isn't the best for your teeth. There are certainly much better alternatives out there that are good for your teeth.


Does not contain fluoride

Unfortunately the vast majority of the activated charcoal toothpastes do not contain fluoride. They're typically marketed towards an audience who seeks an all natural toothpaste. These products will typically label and market themselves as fluoride-free toothpastes.


That is unfortunate because it is fluoride within toothpaste which gives it the ability to prevent and reverse cavities. Without it, your toothpaste is not really offering you much benefit nor protect against tooth decay.


Fluoride may not whiten your teeth but it will certainly strengthen it. The mechanism for how it does so is by replacing the hydroxyl ion with a fluoride one. This transform the enamel tooth structure from hydroxyapatite into fluorapatite.


  • Increased resistance to acid dissolution.

  • Decreases mineral solubility.

  • Increased stability of mineral structure.

  • Promotes remineralization to reverse cavities.


The takeaway is that charcoal without fluoride is missing out on a huge protective effect for your teeth. The whole point of toothpaste is to fight cavities is it not?


Fluoride toothpastes which are better than charcoal

Even though most of the charcoal toothpastes do not contain fluoride, there are some that DO have fluoride in them. Namely it is the ones that come from Colgate and Crest. Yes, they do make a charcoal version of their toothpaste and it does have fluoride in it.


If you really want to use a charcoal based dentifrice we would recommend either one of those over the more "natural" ones. However if you don't care about your toothpaste being able to reverse cavities then you can feel free to do whatever you want. Although that isn't what we would personally do.


Nonetheless, in our opinion any whitening toothpaste which has fluoride in it will be a better choice than one without any.


Does not contain hydroxyapatite

Aside from fluoride, hydroxyapatite based toothpastes also have the ability to stop and reverse cavities. This is a new type of toothpaste and is a fluoride free alternative which everyone should use if they don't want to be exposed to too much fluoride.


Hydroxyapatite toothpastes are able to remineralize your teeth because your teeth are actually made of the same exact material. Your enamel is mainly composed of hydroxyapatite.


A study in the Journal of Dentistry showed that hydroxyapatite toothpastes had a comparable remineralization effect on the enamel. However it was actually superior in regards to remineralizing the dentin.


Verdict

Taking into account everything that we currently know, we would have to agree with the recommendation by the ADA. There isn't enough studies and evidence in regards to the safety and efficacy of charcoal toothpaste. Therefore we are hesitant in recommending it as the primary dentifrice to use on a daily basis.


A better choice would always be to pick a toothpaste that can stop and reverse cavities. That is one of the major selling points to buying a toothpaste. Why even brush your teeth if what you're using doesn't even protect you against cavities?


Overall from a tooth decay standpoint we would say to choose a fluoridated toothpaste or one of the newer hydroxyapatite toothpaste.


However, if you wanted to maximize the whitening effect because having white teeth is the most important thing to you, we would recommend a product with peroxide. The best whitening toothpastes that can remove both extrinsic and intrinsic stains are those which contain hydrogen peroxide.


Charcoal is simply missing that very ingredient so it will never be the best whitening toothpaste. If you were simply choosing to use charcoal for its whitening ability, you may want to reconsider your decision. What will most likely happen is that you're brushing your teeth everyday but they'll still be yellow!


Nonetheless, if you still want to use charcoal because it is all natural, you can but please do it in moderation. You don't want to damage your enamel by overusing it. If anything you should at least alternate with a fluoride one so that you can still protect your teeth. We would be cautious in using it as the primary toothpaste until the ADA explicitly says that it has been proven to be safe.


Those are all of the preventative dentistry tips by our dentists in Long Island City, NY.

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About the author: Dr David Chen, DDS

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Hello, I'm Dr Chen and I'm an actively practicing dentist in Long Island City, NY. I graduated from Columbia University College of Dental Medicine in 2016 but prior to going to dental school I was already working in the dental field. It's been more than a decade since I first got to know dentistry and let me tell you, time flies by quickly. Since then I've developed a fondness for writing, which is how this all got started!

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Medical Disclaimer:

This blog is purely meant for information purposes and should not be used as medical advice. Each situation in your mouth is unique and complex. It is not possible to give advice nor diagnose any oral conditions based on text nor virtual consultations. The best thing to do is to go in person to see your dentist for an examination and consultation so that you can receive the best care possible.

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The purpose of all of this oral health information is to encourage you to see your dentist and to inform you of what you may expect during your visit. Due to the unfortunate nature of dentistry, there isn't really any true home remedies that will get rid of dental problems. Roughly 99.99% of them require in-person intervention by a healthcare professional.

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Hint: That is the reason why you can't eliminate seeing dentists in your life!

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