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6 October 2020

Choosing the best toothpaste

Find out the truth behind the claims made by popular toothpaste brands
Image showing spread of various toothpastes
Olivia Howes

The number of different toothpastes available is staggering. Visit Boots or Superdrug's websites and you’re faced with well over 100 options promising everything from whitening to enamel repair, deep cleaning, germ protection, tartar control and sensitivity relief. How do you choose the right one for you?

To find out, we asked three leading dental health experts, with a wealth of toothpaste knowledge, to assess the ingredients typically found in toothpastes that target sensitivity, whitening and enamel repair to get to the root of whether they are worth it.

They examined research provided by the manufacturers, and wider clinical research, to help you decide whether to pay a premium for types of toothpaste, such as those for sensitive teeth.

While it's true that some claims do stand up to scrutiny, others may be more down to interpretation. And bear in mind that many claims may be based on the inclusion of one key ingredient - fluoride, which can be found in even the cheapest toothpastes.

The importance of fluoride

Brushing with a fluoride toothpaste remains the best thing you can do to maintain your dental health, according to experts. 

Fluoride infiltrates the enamel’s surface and reaches areas that brushing can’t – providing you brush for around two minutes – making the tooth surface harder (remineralising) and more resistant to attack by sugar-loving bacteria. To maximise its benefit, spit but don’t rinse your mouth with water after you finish brushing.

The gold standard of research reviews, Cochrane, found that the use of fluoride in toothpaste leads to less tooth decay. The stronger the concentration, the more decay is prevented. 

Fluoride and tap water

 

Some people may assume they don’t need fluoride in their toothpaste because they are already getting it from tap water, but this isn’t necessarily the case. Only around 10% of the UK population receives water with optimal levels of fluoride. To find out if your area is one of them, visit the BFS website or contact your local water supplier.

A common concern is that consuming fluoridated tap water and using fluoride toothpaste could lead to excessive fluoride consumption, but the NHS says dental fluorosis, a condition that causes pitting or discolouration of children’s teeth caused by excessive fluoride, is uncommon in the UK, as fluoride in the water supply, where it is added, is carefully regulated.

For more advice on looking after your teeth, read our guides on NHS and private dental charges or finding an NHS dentist.

3 key things to look for when buying toothpaste

  •  Check the fluoride concentration. Look for the parts per million of fluoride (ppmF). Less than 1,000ppmF is a low concentration and offers limited or no protection against decay. 1,450ppmF is generally used in over-the-counter UK toothpastes and is recommended by our experts. But children's formulas can contain lower levels.  
  • Think about your needs. Many people – especially those who brush well – don’t need extra active ingredients apart from fluoride.  If you have specific concerns around things such as whitening, sensitivity or enamel wear, see our ingredients guide (below) to understand the claims made about a particular toothpaste, and whether the evidence supports them.  
  • Check the pack size. A toothpaste that looks cheap can be pricey when you calculate the price per 100ml compared with rivals.

Toothpaste for sensitive teeth

Dentine sensitivity is believed to be caused by fluid moving up the tiny tubules connecting tooth dentine to the nerve. Temperature changes, pressure, or sweet or acidic food can influence the fluid’s movement. 

To try to combat it you can either desensitise the nerves or block the tubules. Toothpastes that claim to treat sensitive teeth are considered medicinal products and are subject to Medicines and Healthcare Products Regulatory Agency (MHRA) rules around how they are marketed. 

Our experts examined some of the key ingredients used in popular toothpastes and found all have good evidence to support them, but one type may work better for you than another.

All desensitising toothpastes will be more effective if you reduce the acidic food and drinks you consume between meals. You may find that your hypersensitivity resolves naturally over time, or it may be an intermittent problem.

The main active ingredients aimed at sensitivity are:

Potassium Nitrate

Potassium nitrate is the desensitising ingredient found in Sensodyne Original - perhaps the most well-known toothpaste formulated for sensitive teeth. There’s good evidence potassium nitrate builds up over time to desensitise nerves. However, the time taken to work is the downside – it can take up to two weeks to be effective.

Stannous Fluoride

A more recent innovation in the world of dentine hypersensitivity, stannous fluoride is one of the three types of fluoride that can be found in toothpastes, and is found across Oral B's Pro-Expert range and also in Sensodyne's Rapid Relief toothpaste. It blocks the tubules and works very quickly.

Arginine

Arginine is Colgate’s weapon of choice against sensitivity. It combines with calcium carbonate to block tubules and should start working rapidly.

Whitening toothpastes

Whitening toothpastes are on shakier ground when it comes to whether they live up to their claims or not.

There are two types of staining that affect the ‘whiteness’ of your teeth:

  •  Intrinsic staining happens inside your teeth and can be caused by trauma, certain medical treatment or excessive childhood fluoride consumption (but this is rare in the UK). Teeth also yellow as we age, due to thinning enamel. The only way to remove intrinsic staining is bleaching through dentist-administered professional products (using hydrogen peroxide).
  • Extrinsic staining is typically caused by smoking, or drinking tea, coffee or red wine. It responds well to brushing with whitening toothpaste, which contains ingredients to help remove stains, but won’t change the underlying colour of your teeth. 

So as long as you don't have expectations that a whitening toothpaste will change the underlying colour of your tooth enamel, there may be value in buying a toothpaste which makes whitening claims, as it could contain stain-removing ingredients that a standard paste won't have.

Here's a rundown of the evidence behind typical ingredients found in whitening toothpastes:

Hydrogen peroxide

The UK legal limit allows a concentration of 0.1% in a toothpaste, compared with 6% in a professional whitening treatment, so any toothpaste containing this is unlikely to have much effect on underlying enamel colour.

Optic brighteners

Another method for whitening is the use of a film that coats the teeth to provide an optic whitening effect. Blue covarine is a typical optic brightening ingredient. These might have an immediate effect, but won’t last as saliva washes away most paste quite rapidly. 

Sodium bicarbonate

Sodium bicarbonate is an effective stain remover with mild abrasive action. It also has some anti-bacterial properties. It’s a favourite for ‘natural’ toothpastes, for example Arm & Hammer uses it across its range.

Charcoal 

Charcoal whitening toothpaste has seen a huge rise in popularity, despite the Oral Health Foundation and our experts agreeing there’s not enough evidence to support claims around its whitening effect. 

Charcoal, in some higher strength formulations, can also be too abrasive, which could wear down tooth enamel over time. Furthermore some charcoal toothpastes are also fluoride-free, which our experts would not recommend.

Enamel Repair toothpastes

There have been some innovations in this area in recent years and there may be good reason to choose a toothpaste targeted at repairing enamel. 

But, bear in mind all fluoride toothpastes provide some protection against enamel erosion, and fluoride is the basis of many an enamel repair claim, as it works to harden or ‘remineralise’ enamel.  

If you suffer from enamel erosion, talk to your dentist too. They may suggest alternatives, such as changing your diet or brushing technique, using fluoride mouthwashes separately to brushing, or professional application of fluoride varnish.

Fluoride

There are three types of fluoride: sodium fluoride, sodium monoflurophosphate and stannous fluoride. 

All will help with remineralisation and therefore, can be said to repair enamel. But manufacturers of enamel repair pastes are likely to base their claims around the particular formulation of their paste assisting with optimal uptake and absorption of the fluoride.

Calcium silicate and sodium phosphate

Unilever’s Regenerate Enamel Science Advanced toothpaste claims to regenerate enamel through the action of calcium silicate and sodium phosphate interacting with hydroxyapatite (what tooth enamel is made of). 

Our experts agreed that the lab studies show the patented formula (combined with glycerine rather than water – this is its ‘NR5 technology’) could be causing changes to teeth that could be interpreted as regrowth. But this is an expensive option when alternatives may work for you - especially as some claims are based on using an additional booster serum.

Other toothpaste ingredients and what they do

  • Hydrated silica, mica, calcium carbonate - abrasives that will clean and polish. A toothpaste’s level of abrasion is known as its RDA (relative dentin abrasivity). Most toothpastes will have a fairly low level but whitening toothpastes can sometimes be more abrasive.
  • Cellulose gum, carrageenan and xanthan gum -these thickeners provide texture and stop toothpaste drying out.
  • Artificial or added sweeteners and flavour providers - ingredients such as limonene, cinnamal, peppermint oil, sucralose, lota carrageenan, sodium saccharin, aroma and mint flavour are there to improve the taste. The first three essential oils are known allergens.
  • Sodium hydroxide - also known as lye, it neutralises the pH of other ingredients.
  • Sodium Lauryl Sulfate (SLS) - a foaming detergent that dissolves dirt and grease. It can be quite harsh. A 2019 systematic review found that SLS-free toothpastes reduced the number and duration of mouth ulcers so if you suffer from these, you may want to choose a toothpaste without SLS. Alternatives include cocamidopropyl betaine, lauryl glucoside and disodium cocoyl glutamate.
  • Humectants - such as sorbitol, glycerol, glycerin, propylene glycol, keep your toothpaste moist.
  • Tin Oxide - provides colour (red) and may also have an antibacterial affect.
  • Titanium dioxide - this colour pigment makes toothpaste whiter and brighter.
  • Zinc - a replacement for triclosan which, although not banned in the UK, has now been removed from most toothpastes over concerns about its safety. Zinc has antibacterial properties and is a common ingredient in toothpaste, but experts agree that the most important factor in removing bacteria is brushing effectively.

Eco, natural and vegan-friendly toothpastes

There are now a significant number of products that market themselves on their eco, vegan or sustainable credentials. 

Toothpaste tablets that you chew aim to cut down on the waste generated by toothpaste tubes (which generally can't be recycled because they are mixed materials). 

You can also buy vegan toothpastes which means they don't contain animal products, but are also cruelty free (have not been tested on animals).  Some toothpastes advertise their natural ingredients such as coconut oil or charcoal, or the absence of palm oil.

But bear in mind that switching to a brand for any of these reasons should not, and does not need to, come at the expense of your dental health. 

What to watch out for

Fluoride-free formulas - some products making natural claims are also fluoride free. This puts you at increased risk of dental caries, no matter how carefully you brush.

Tablets - the majority of scientific research has been done into how pastes work in combination with brushing, not tablets, so there is no guarantee that these will offer the same protection. Watch out for ones that are also fluoride-free (see above).

Colgate has recently launched a vegan 'Smile for Good' toothpaste which has fully recyclable packaging and also contains fluoride. 

Kingfisher sells fluoride versions of its fennel and mint toothpastes and there are other sustainable toothpastes brand available that don't leave out the fluoride.

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