By now I’ve lost count of how many times I’ve been asked about home teeth whitening kits. From my family and friends, to people DM’ing me on instagram asking whether or not they work.
Now I’m not out here to throw shade on all of these companies on social media that are selling at home whitening kits, that claim to take your teeth 8 shades whiter. I’m going to try to do this as tastefully as possible. I’m here to educate you guys on why to steer clear of them, opposed to slander them for capitalising on a fad product.
When scouring through the HiSmile website I could only find two ingredients in their products, that they claim whitens teeth, so I’m simply going to go in to detail about them both.
The first ingredient which they claim whitens the teeth is sodium bicarbonate or as you might find it in your kitchen cupboard, baking soda.
STORY TIME… I think my love for dentistry stems from my primary school history lessons and how my teacher taught as that dental appearance has been linked to social class throughout history. In the times of Tudor rule you were thought to be rich and from a high social class if you had teeth riddled with decay brown/ black teeth. This was because as we now know, sugar causes tooth decay which can turn your teeth brown/ black , and if you could afford sugar in those days you were thought to have a lot of money.
Opinions changed during the Victorian times when baking soda was used to clean the teeth. It was noted that baking soda appeared to make the teeth visibly whiter and so, for decades now, it is often a key ingredient in whitening toothpastes, but does it actually work, and if so how?
If you’ve ever mixed some baking soda with water you’ll know that it forms quite a gritty paste. Keyword being gritty. This gritty paste is abrasive to the teeth, just like how a nail-file wears down the nail, over time, baking soda will do this to the enamel of your teeth.
Just for a bit of foundation knowledge I want you to know the outer two layers of your teeth. The most outer layer is the enamel, which is the hardest tissue in the body and gives our teeth a grey/ blue-white colour. The layer below this is called dentin, it’s around 9 times softer than enamel is and is more yellow in colour.
Baking soda has been proven to remove ‘extrinsic surface staining’. This is basically staining to the teeth that is caused by the things we all love to indulge in such as; red wine, coffee, curries, pasta sauces, as well as smoking. So yes it’s great because your teeth appear whiter than before but once you start eating and drinking all of these foods again the staining is going to come back. Also it isn’t bleaching your teeth to make them more white it’s simply getting rid of some of the staining.
The bad side to it is that the abrasiveness of the baking soda paste will, over time, wear down your enamel. This means that your dentin will become more exposed, there are two negative impacts of this. Firstly I said how enamel is white in colour and dentin is more yellow in colour. Well if the dentin becomes more exposed it means that your teeth are going to appear more yellow, which is what you were trying to prevent in the first place!
Secondly dentin contains these tiny little tube-like structures which help sense pain and sensitivity of the teeth, because they’re now more exposed you’re more likely to experience sensitivity to hot and cold. Oh and to top it off remember how I said that dentin is around 9 times softer than enamel? Well if the baking soda managed to destroy the enamel, imagine what’s going to happen to the dentin!
Now baking soda acts in this abrasive way through mechanical processes such as brushing your teeth, with the HiSmile gels it’s simply sitting on your teeth while the UV light supposedly gets to work to whiten your teeth. This means that it’s not acting in an abrasive way. So if it’s not acting in an abrasive way then surely it’s not actually doing anything to remove those surface stains.
Sodium chlorite is often used as a whitener in paper industries, so you’re probably thinking ‘what’s the issue with it?’
Firstly sodium chlorite/ sodium dioxide gels are usually quite acidic and are often coupled with citric acid. These acidic gels over time will chemically erode the enamel on your teeth away and in turn make your teeth appear more yellow, again, due to more exposed dentin that I mentioned earlier.
Also the edges of your teeth can appear more see-through and studies have shown that it can also make your teeth look less shiny and a lot more dull. Along with all of this this, you’re going experience a lot more sensitivity, so you can wave bye-bye to that ice cold pint or piping hot, hot chocolate.
In a recent article written by Dr Linda Greenwall, it was stated that there are some more serious effects of using sodium dioxide gels, some users have shown heart irregularities and breathing difficulties.
Another thing I want to quickly mention, is that a lot of these influencers advertising HiSmile and similar products, ahem, Kylie Jenner, have veneers. Now you can’t whiten veneers whether it’s using these home-kits or professional whitening from your dentist because unlike natural tooth structure the materials used for veneers do not have pores that absorb the whitening agents.
Talk about false and misleading advertising.