Teeth Whitening Toothpaste: Does it really work?

If you've ever wandered down the oral care aisle of a supermarket, you've probably noticed the abundance of teeth whitening toothpaste on the shelves. Each promises a brighter smile but the big question is: Do they really work? Let’s explore the facts behind these products, including what the research says.

How does teeth a whitening toothpaste work?

Before we start, it is important to understand one thing about the colour of our teeth; it is that, the colour primarily comes from the dentin, which is the inner layer of the tooth. Dentin is typically pale yellow and is influenced by the enamel, that is the outer layer. The enamel basically acts like a window, as its thickness and translucency can make teeth look lighter or darker.

The colour of our teeth can change with time due to various reasons, causing extrinsic and intrinsic staining. Let's look at how the ingredients in a teeth whitening toothpaste work to tackle those stains.

1) Abrasive agents

Most teeth whitening toothpastes function by incorporating abrasives. Dark foods and drinks like coffee or tea, as well as habits like smoking can cause pigments to build up on the outer surface of the teeth, leading to what is known as extrinsic stains. The abrasive agents remove these stains by gently scrubbing and polishing them away. This is how most teeth whitening toothpastes work.

Examples of abrasive agents in teeth whitening toothpaste include hydrated silica, sodium metaphosphate, calcium pyrophosphate, calcium carbonate and aluminium oxide.

Lately, activated charcoal has gained popularity in the world of teeth whitening toothpastes. This is because activated charcoal is porous and can adsorb pigments and stains. However, it is important to note that no comprehensive studies are confirming its effectiveness, hence more research is needed to determine how well it works.

2) Chemical agents

When stain build up within the tooth itself, they are known as intrinsic stains. They are caused by factors like aging, certain medications or trauma to the tooth. For intrinsic stains, teeth whitening toothpastes often include bleaching agents. These agents work by breaking down the pigments that cause the discolouration, essentially whitening the tooth from the inside out.

When choosing a teeth whitening product, it's important to consider the whitening ingredients used, as they play a key role in the effectiveness and safety of the product. Many teeth whitening products contain ingredients like hydrogen peroxide and carbamide peroxide.

In Singapore, the use of hydrogen peroxide in dental products is strictly regulated. According to the Health Sciences Authority, "Dental products containing more than 0.1% hydrogen peroxide are only allowed to be used by or supplied through registered dentists." This means that over-the-counter whitening toothpastes contain less than 0.1% hydrogen peroxide. This concentration is much lower compared to the 30% and higher often used in professional in-office whitening treatments, which is why teeth whitening toothpastes bought over-the-counter tend to have limited whitening effect.

3) Optical brighteners

Some whitening toothpastes contain optical brighteners, which are special dyes designed to temporarily enhance the whiteness of your teeth. The principle behind this involves colour theory. On the colour spectrum, blue is directly opposite yellow. By depositing a blue layer on the surface of teeth, they reduce the visibility of yellow discolouration, therefore creating a visual effect that makes teeth look more white. 

Examples of optical brighteners include blue covarine and FD&C Blue No. 1.

A study from 2019 demonstrated how blue covarine works to make teeth appear whiter. It forms a thin, semi-transparent blue layer on the surface of teeth. This blue film alters the way light interacts with teeth, making them look brighter instantly. However, it is important to note that optical brighteners only provide a temporary boost in whiteness and they don’t actually change the natural colour of teeth.

4) Herbal ingredients

There are whitening toothpastes that incorporate natural herbal ingredients as an alternative to conventional formulations. This shift is partly due to concerns that abrasive ingredients in some toothpastes can wear down enamel over time and that chemical agents might increase tooth sensitivity.

Examples of herbal ingredients include papaya (papain enzyme), meswak and cloves.

A study conducted in 2018 found that toothpastes containing these herbal ingredients provided whitening results comparable to those of conventional whitening toothpastes. Herbal toothpastes were shown to cause less wear on the tooth surface, making them a gentler option. However, while the initial findings are promising, further research is needed to fully understand their long-term effectiveness.

Click here to read our article on 5 ways how to whiten teeth naturally.

5) Newer ingredients: Hydroxyapatite toothpastes

Hydroxyapatite (HA) is a mineral that closely resembles the natural composition of our bones and teeth, making it a highly effective ingredient in dental care. The use of HA in dental care has an interesting backstory. It was first introduced by NASA in the 1970s as a toothpaste for astronauts who were losing minerals in their teeth and bones due to zero gravity in space. This early innovation laid the groundwork for modern HA toothpastes, which now contain nano-hydroxyapatite particles.

These tiny HA particles bond with your enamel, filling in small cracks and gaps. This process not only repairs and strengthens teeth but also creates a white, opaque layer on the surface, making teeth appear more white. While HA toothpastes shows potential, more research is needed to fully understand its long-term impact.

Not all teeth whitening toothpastes are the same. In fact, most whitening toothpastes are formulated primarily to address extrinsic stains caused by food and drinks or smoking, rather than brightening teeth via bleaching.

The way they work—and how effective they are—depends on the specific ingredients they contain. So next time you’re browsing the toothpaste aisle, don’t just grab the first whitening toothpaste you see; take a moment to read the ingredients and choose the one that’s right for you.

Related Articles

• Can Sensitive Teeth Be Whitened?: Tips and Precautions!
• How Does A Professional Teeth Whitening Kit For Home Use Work?

What are the disadvantages of using a teeth whitening toothpaste?

Teeth whitening toothpastes seem like a simple solution: By brushing with these toothpastes regularly, your teeth should gradually become brighter. However, there is more than meets the eye. Here are some disadvantages of using a teeth whitening toothpaste.

Limited whitening effect

Teeth whitening toothpastes mainly work on extrinsic stains but may not work as well on intrinsic stains, which are located deeper within the tooth structure. Intrinsic stains often require more intensive treatments such as professional teeth whitening procedures to achieve significant results.

Potential for tooth wear

Many teeth whitening toothpastes include abrasive ingredients that help scrub away stains. While these abrasives can be effective at removing surface discolouration, they might also wear down the enamel over time, leading to increased sensitivity and the risk of tooth decay.

Increased tooth sensitivity

Some teeth whitening toothpastes use chemical agents like hydrogen peroxide or carbamide peroxide to lighten your teeth. These chemicals can exacerbate tooth sensitivity for those who already have sensitive teeth. For such cases, selecting a product that includes potassium nitrate can be beneficial as it helps reduce teeth sensitivity commonly associated with whitening. By carefully selecting the right teeth whitening products, you can achieve a whiter smile without compromising your comfort.

Slow results

It can take several weeks before you notice any difference. Plus, if you continue habits that cause new stains—like drinking coffee or smoking—you might not see much improvement or you could even reverse the progress you’ve made. Research has shown that while you might see some improvement after four weeks, it’s usually modest and varies from product to product.

Inconsistent results

As mentioned, the effectiveness of whitening toothpastes can vary based on the specific formulation and individual factors such as the type of stains, the condition of your teeth and your overall oral hygiene routine. Some people might see noticeable results, while others may find the improvements to be minimal.

So, does whitening toothpaste work?

In short, teeth whitening toothpaste can help get rid of surface stains and might make your teeth look a bit brighter but it will not alter the natural colour of your teeth or provide dramatic whitening results. It is a good option for those seeking a slight improvement or wanting to maintain their whiteness after a professional treatment. Newer materials like Hydroxyapatite toothpaste has recently been introduced to the market but more research is needed to assess their efficacy.

For more noticeable changes, professional treatments at a dental clinic are your best bet! Looking to book your teeth whitening appointment with us? Just send us a message here and we will be right with you.

References

1. Vaz, V. T. P., Jubilato, D. P., Oliveira, M. R. M. D., Bortolatto, J. F., Floros, M. C., Dantas, A. A. R., & Oliveira Junior, O. B. D. (2019). Whitening toothpaste containing activated charcoal, blue covarine, hydrogen peroxide or microbeads: which one is the most effective?. Journal of Applied Oral Science, 27, e20180051.
2. Joiner, A. (2010). Whitening toothpastes: a review of the literature. Journal of dentistry, 38, e17-e24.
3. https://www.hsa.gov.sg/consumer-safety/articles/online-diy-teeth-whitening-kit-pain
4. Kalliath C, Mukunda A, Pynadath M, Venugopal V, Prethweeraj J. Comparison between the effect of commercially available chemical teeth whitening paste and teeth whitening paste containing ingredients of herbal origin on human enamel. Ayu. 2018 Apr-Jun;39(2):113-117. doi: 10.4103/ayu.AYU_82_18. PMID: 30783367; PMCID: PMC6369603.
5. Chen L, Al-Bayatee S, Khurshid Z, Shavandi A, Brunton P, Ratnayake J. Hydroxyapatite in Oral Care Products-A Review. Materials (Basel). 2021 Aug 27;14(17):4865. doi: 10.3390/ma14174865. PMID: 34500955; PMCID: PMC8432723.