Everything you need to know about teeth whitening (2024)

Concerned about the colour of your teeth and considering your whitening options? If your teeth are less than pearly white and you long for a dazzling Hollywood smile, you might have considered purchasing a teeth whitening kit online. But DIY teeth whitening does come with a number of risks so it's always best to opt for a procedure carried out by a dentist.

We spoke to Dr Ahmed Hussain, Principle Dentist at Harrow on the Hill Dental Practice about the best teeth whitening tips:

What is teeth whitening?

Genetics, the environment, lifestyle, diet and ageing can all make teeth look yellow and darker. The most common reason for yellow teeth are surface stains on your enamel, which are usually caused by what we eat and drink, or if we smoke.

Over time, these stains can work their way to the layer below enamel, known as dentin. When this becomes stained, the whole tooth looks darker because of the translucency of enamel. In addition, an erosive diet (fizzy or sports drinks, or acidic foods) can thin the dental enamel which makes the teeth look yellower as the dentin below shows through.

However, there are plenty of things we can do to prevent yellowing or stained teeth. Whitening is such an easy, non-invasive and healthy way to obtain a dazzling smile. My patients want a healthy looking smile, but appreciate that it needs to look natural.

I would recommend a chairside or at-home teeth whitening treatment, followed by two weeks of at-home whitening to take the colour to its optimum shade. However, if you haven’t been to the dentist in a while, your treatment may take longer as we’ll need to make sure there are no underlying gum health problems before whitening.

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Types of teeth whitening

My favourite whitening method is Philips Zoom At-home Whitening. In-clinic Zoom whitening is good for short term results like for an event when time is a factor. But for longer lasting results we recommend the bleaching tray as it locks in the new shade for longer and can easily be topped up using the same trays in the future.

There are other teeth whitening systems, which also give a great result as long as they are applied by a dentist.

Whitening toothpastes (including charcoal based toothpastes), white strips and oil pulling should be used with caution as they work by removing surface stains hence brightening the colour. However, over time the enamel will thin, which also causes the teeth to become darker.

Who can do teeth whitening?

Teeth whitening is a safe and effective treatment when delivered by a dental professional. It is actually illegal for anyone other than a dentist to prescribe tooth whitening treatment.

Home tooth bleaching is ubiquitous on social media, despite being illegal without a prescription from a dentist.

Teeth whitening is something that needs to be done by your dentist. The problem with getting your teeth whitened by anyone but a dental professional is that carried out incorrectly, whitening can result in major damage to the gums, enamel or roots. It can also lead to zinging tooth sensitivity.

Who knows the long-term damage these non-professional treatments might cause? Not to mention, they probably won’t be effective – for example, tooth whitening products need to contain six per cent bleach to give us pearly whites, but over the counter treatments only have 0.1 percent bleach.

What happens during a teeth whitening procedure?

If you decide to get your teeth whitened, during the procedure at your chosen dental clinic you can expect the following to occur:

• At the start of an in-clinic whitening treatment, your dentist will take a mould of your teeth, using either putty impressions or a 3D digital scanner. This mould will be used to create a set of custom plastic trays for your teeth, which will fit over your teeth perfectly. These will be given to you to use at home with specially prescribed tooth whitening gel.
• Before in-practice whitening your dentist will prepare your teeth, placing cheek retractors in your mouth to pull back your lips. Then to ensure your gums and lips are protected, they will apply protective gauze and masking gel on your gums around your teeth, so only your teeth come into contact with the bleaching gel.
• You will be given safety eyewear, and your dentist will then apply the whitening gel to your teeth. They will then shine a special light on your teeth for four x 15 minute cycles, topping up the gel on each occasion. This light accelerates the oxygenation of the whitening gel, which means you can walk out of the practice with brighter and whiter teeth.
• You will then take home your individualised whitening trays, which will allow for up to two weeks of top ups at home.
• If you plan to have an at-home whitening treatment, you will visit your dentist to be fitted for your whitening trays, and you will have a dental health check up at the same time.
• You will collect your trays at your dental practice at a time convenient for you. The dentist will make sure you are happy with how the trays fit and you know how to use them. You will then apply the gel in your trays once a day, night or day, for two weeks for the optimum result.

What is Zoom teeth whitening?

I find my patients have the best results with Philips Zoom Whitening, especially with the At-Home kit. As well as whitening, the solution applied to teeth helps protect enamel and reduces sensitivity, which is something previous tooth whitening treatments could exacerbate.

In-clinic Zoom Tooth Whitening gives the most intense results, as it contains accelerating ingredients to get to work and reverse staining. This kind of whitening is especially effective if you have deep discolouration, maybe from years of smoking, drinking wine and coffee, or taking certain types of medication. As your dental professional carries this out for you, you can be sure you’re getting a safe whitening treatment.

At-home Zoom Tooth Whitening allows you to brighten your smile gradually and conveniently with a teeth bleaching treatment that fits into your schedule. You will get customised whitening trays that fit every contour of your teeth for even results and will have whiter teeth in one-two weeks.

How does teeth whitening work?

The peroxide solution bleaches the enamel, which is the outer covering of the tooth, and the dentine, which is the inside of the tooth. This whitens your teeth safely and effectively.

The Philips Zoom Whitening in-clinic system uses equipment that shines a bright light to activate the hydrogen peroxide gel, applied to your teeth. This produces oxygen that removes the stains. It is safe and effective when done by a dentist. We look after the whole mouth and not just the teeth. We take care about any minor sensitivity that may occasionally arise.

The at-home system works in much the same way, without the LED light. The gel contains six percent hydrogen peroxide solution, which whitens your teeth over the course of one to two weeks.

What are the benefits of teeth whitening?

Your teeth will look whiter and fresher. It’s amazing to see how much whiter teeth can improve a smile quickly and inexpensively.

What are the risks of teeth whitening?

If your dentist is conducting your tooth whitening, the risks are minimal. Teeth whitening can lead to some sensitivity due to the peroxide solution. However, the whitening solution I use helps protect enamel and reduces sensitivity. If you are at greater risk of sensitivity, you can also apply an Amorphous Calcium Phosphate (ACP) gel to your trays after your treatment. Your dentist can prescribe the gel for you, which helps rebuild enamel and reduce sensitivity.

There is a risk of damage to your gums if you don’t visit a reputable dentist, and at-home kits can cause many issues like tooth sensitivity to hot and cold, gum burns and damage to tooth enamel.

What can you do to avoid risk?

Always visit a dentist to whiten your teeth, and advise them if you suffer from tooth sensitivity, as they will be able to advise the best course of treatment for you.

How long does teeth whitening last?

Tooth whitening treatments last for about six months. You can extend the effects by minimising stains forming on the surface of your teeth, which are often caused by what we eat or drink. Reduce your consumption of tea, coffee, red wine and food containing tannins and turmeric, which can all stain your teeth.

Brush and floss your teeth daily, and get a professional clean regularly with a hygienist.

You can also top-up your whitening at home using your customised whitening trays, with new gel syringes which you can buy from your dentist.

Last updated: 23-06-2021