You may be surprised but whitening toothpaste does work. However not all of them were created equal because they utilize different whitening ingredients.
Some whitening toothpastes will only remove extrinsic stains while others can remove both extrinsic and intrinsic stains. What differentiates them from one another is the ingredients that they use to whiten your teeth.
Therefore we can categorize the whitening ingredients in toothpaste based on what type of stains they can remove.
- Extrinsic stains only
- Intrinsic and extrinsic stains
Whitening ingredients in toothpaste that remove extrinsic stains only
According to an article in the Journal of Dentistry, the abrasive system is a key functional ingredient in whitening toothpastes. In fact, studies have also shown that the abrasiveness of is actually the main determining factor for toothpastes which whiten by mechanical removal of extrinsic stains.
Here is a common list of abrasive ingredients in whitening toothpastes:
- Silica (silicon dioxide)
- Hydrated silica (hydrated silicon dioxide)
- Sodium bicarbonate
- Calcium carbonate
- Activated charcoal
- Aluminium silicate
Mechanical removal of extrinsic stains with abrasives is the action of physically brushing your teeth to remove the stain. Essentially it is the scrubbing action of the toothpaste with the toothbrush that mechanically gets rid of the staining.
This action is similar to scrubbing the floor to remove any debris on it. Since it whitens the enamel purely by mechanical means, it can only remove surface stains. That is why it is referred to as removing extrinsic stains.
What abrasives will not do is remove intrinsic stains which are deeply embedded inside of the tooth. The reason is simple, you can’t brush the inside layers of the teeth only the outer one. If you keep brushing your teeth but they’re still yellow, it probably means that toothpaste only has abrasives and nothing else.
Silica is an abrasive that is often used in toothpastes. It is the second most abundant mineral on the planet earth. They make up approximately 26% of the earth’s crust by weight.
Hydrated silica is simply the hydrated form of silica. To make it, you heat it up and dissolve it in water. Then it is mixed with acid and precipitated, thereby turning into a solid. You can then use this as a whitening abrasive in toothpaste.
Sodium bicarbonate is another name for baking soda. Yes, it is the same ingredient as what you currently have in your pantry.
According to the ADA, it is one of the most effective abrasives for whitening your teeth, even more so than other abrasives. In fact, it is also the most gentle one on your enamel so it won’t erode it from being too abrasive.
Here is a chart showing various toothpastes and their abrasiveness and as you can see, only water is less abrasive than sodium bicarbonate.
This is actually a mineral and it contains a lot of calcium as its name implies. In fact, it is used for upset stomachs since it is often found in antacids.
Despite its wonderful effects on your digestive system, it also doubles up as an effective tooth whitening ingredient due to its mild abrasiveness. Studies have shown that it can effectively whiten your teeth.
The internet fad about using charcoal to whiten your teeth is not baseless. Studies have shown that it is due to the abrasiveness of the activated charcoal which gives it its whitening ability.
However it would be prudent to use it in moderation since it is currently not approved by the American Dental Association. According to them there is insufficient evidence on its safety and efficacy. There has been some claims about it potentially being too abrasive on your enamel.
This whitening ingredient in toothpaste is simply another derivative of silica. Therefore it is a mineral as well. The difference is that it contains aluminium in its structure.
Whitening ingredients that remove intrinsic and extrinsic stains
The only whitening ingredient in toothpaste or any other whitening product for that matter is hydrogen peroxide. It doesn’t necessarily have to be hydrogen peroxide because it can also be a derivative of it such as carbamide peroxide. As long as it has peroxide, it will be able to bleach your teeth white.
Hydrogen peroxide is able to whiten your teeth because it can chemically oxidize intrinsic stains. It does so by diffusing through each layer of the tooth and even reaching the pulp within 15 minutes of application.
It is due to its ability to penetrate through the tooth that it can remove more than just extrinsic stains. Mechnical removal of stains via abrasives can only affect the exterior layer of the enamel because it can’t reach the inner layers. For that reason alone, it is necessary to have an intrinsic stain remover in order to have the best whitening result.
The concentration of peroxide within the product also affects the speed at which it whitens. That means that a stronger one will whiten faster while a less concentrated one will whiten slower. However research has shown that all peroxide products can potentially bleach your teeth to the same whiteness when given enough time.
Related content: how long does it take to whiten your teeth with hydrogen peroxide.
What about non-peroxide whitening agents?
There has been a recent trend of new products that can whiten your teeth with no peroxide. These whitening ingredients are touted as peroxide-free.
- Phthalimidoperoxycaproic acid (PAP)
- Sodium percarbonate
However upon further research, we found that both of these ingredients were still derived from hydrogen peroxide or use it to make it. The name may not have peroxide in it but is it truly peroxide free?
Stain prevention ingredient in toothpastes
In addition to whitening ingredients, toothpastes also have stain prevention agents in it. These don’t necessarily whiten your teeth from yellow to white but what they will do is keep them white. They prevent the stains from yellowing your teeth in the first place.
Stain prevention ingredient in whitening toothpastes:
- Polyvinylpyrrolidone (PVP)
How pyrophosphates prevent stains
Pyrophosphates are a tartar control ingredient, which prevents the formation of calculus.
Studies have shown that the mechanism via how it works is by pyrophosphates adsorbing into the calcium sites of enamel. While there they block the formation of further crystal growth.
What that means is it prevents plaque from trying to attach to the surface of enamel. That makes it a good stain prevention agent because plaque and tartar can acquire a lot of stains.
However the downside to using pyrophosphates is that they may also result in teeth sensitivity. The mechanism by how it prevents tartar formation will also prevent your teeth from replenishing the smear plugs that occlude the dentinal tubules.
How polyvinylpyrrolidone (PVP) prevents teeth staining
It is not clear as to how polyvinylpyrrolidone prevents teeth staining except for the fact that it IS effective in doing so.
The prescription antibiotic rinse, chlorhexidine is notorious for staining teeth despite its incredible ability to reducing plaque.
- Studies have shown that it significantly reduced the teeth staining.
- A different study reported that while it was effective in preventing extrinsic stains, it lowered the plaque removal ability of chlorhexidine.
Based on the fact that it reduced plaque prevention, we would assume that it works differently than the pyrophosphates. The latter was successful in preventing the formation of plaque.
Therefore it definitely works via a different mechanism and we don’t know if it has any effect on tooth sensitivity. Nonetheless, it does appear to be an effective extrinsic stain preventing agent.
Which ingredients will make your teeth the whitest?
Obviously the best whitening toothpaste will have all three of the whitening ingredients and stain prevention agents in its formulation.
- Extrinsic stain remover
- Intrinsic stain remover
- Stain prevention ingredient
Currently the whitening toothpaste which has all three of them is the Colgate Optic White Pro Series. That is also the toothpaste which we consider to be the most effective whitening toothpaste.
In our opinion, as long as the toothpaste has an abrasive it will whiten by mechanically removing extrinsic stains. That isn’t an area where the most abrasive is the best because too rough could abrade your enamel.
However for intrinsic stain removal, the higher the concentration of peroxide the more effective it will be. The optic white toothpaste has the highest concentration of peroxide on the market and that is why we crown it as king.
The stain prevention ingredients are typically found in most toothpastes as long as it is labeled as whitening. The only dentifrices which don’t have them are the ones meant for sensitive teeth.
Therefore the criteria for the best whitening ingredients would be:
- Any abrasive would do
- The highest concentration of peroxide
- Any stain preventing agent is ok
Feel free to try various toothpastes for whitening your teeth but we’re just saying that we’ve already found the best one. A close second would be the Crest 3D white professional ultra white toothpaste with 4% hydrogen peroxide. Its second purely based on the fact that it has 1% less peroxide than the optic white.