Not so long ago a toothbrush was a humble thing. A stick, in essence, with some bristles on the end. But with the rise of the electric toothbrush, they’ve become high-tech accessories. You can buy toothbrushes with associated apps, toothbrushes that automatically access the internet and order you new accessories when they divine that you need them and, for some reason, toothbrushes that are artificially intelligent. They can cost as much as a flatscreen TV or an engagement ring.

An estimated 23 million people in Britain now use electric toothbrushes. Their rise is partly driven by our – somewhat belated – national realisation that oral health is important, and by the fact that we have more disposable income than we did a generation ago.

But it is also a story about the rise of an industry; about a struggle between market pressures and medical requirements; about the blurry line between research and public relations. And, in the end, about whether spending the cost of a weekend away on an ergonomically designed, ultrasonic, matte-black thing which looks like a defunct lightsaber will actually do more good than a £1.50 manual toothbrush from the supermarket. Is the electric toothbrush just a marvel of modern marketing or does it deserve plaudits for achieving what frustrated dentists (and parents) have struggled to do: getting us to spend a little more time brushing our teeth?


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The early ones looked like a toilet brush,” says Rachel Bairsto, laughing. She’s the head of the British Dental Association’s in-house museum. Like so many things, electric toothbrushes are probably older than you think. Fridus van der Weijden, a professor of periodontology at the University of Amsterdam, says that early ones existed in the 1930s. But it wasn’t until the 1960s that affordable versions were readily available. One of the early British ones, the Halex Dental, does indeed look like a toilet brush. Its bristles moved in a strange spiral motion. “I don’t think it was very effective,” Bairsto says, laughing again.

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Toothbrushes are centuries old – bone-handled, badger- or pig-bristled things were first made in 1780. “They were beautiful things, a fashion accessory,” says Bairsto. The manufacturer, Addis, still exists today. But it wasn’t until the start of the 20th century that they started to become more mainstream. The thing that really kicked them off was war.

In 1899, the British Army was recruiting troops to fight in the Boer War and recruiters were appalled at the health of the men who were turning up. They were stunted, malnourished and had appalling teeth. “It became a national scandal,” Bairsto says. “No one was cleaning their teeth. Many couldn’t chew their food.” The shocking dental health of the nation’s fighting men catalysed a national campaign: dentists were sent to schools to teach brushing technique, setting up “toothbrush clubs” so poorer children could buy brushes. Then came the First World War; returning soldiers, with a toothbrush in their knapsack, spread the habit. The arrival of plastics – the first celluloid-handled brushes were in Woolworth’s in 1908 while nylon bristles replaced animal-derived ones during the Second World War – made them cheaper too.


Then, in 1954, a Swiss inventor, Dr Philippe-Guy Woog, patented the first practical electric toothbrush, the Broxodent. The American Dental Association rapidly endorsed its use and electric toothbrushes quickly took off in the States. (A rival had one of the most well-known slogans of early TV advertising: “You brush with an ordinary toothbrush; but you BRRRRRRUSHHH with a Brossette.”) The British were slower off the mark, but, by the end of the 1960s, there were several on the market. A 1969 copy of Which? Magazine compared various versions of the early electric toothbrushes available to Britons, and found a total of 15, from eight different companies.

The first electric toothbrushes left a lot of room for improvement. They were large and clunky; battery-powered, only two of them rechargeable; and they were expensive. A standard manual toothbrush at the time cost about two shillings and sixpence, or about £2 in today’s money; the electrics went from a bit shy of £2 (about £30 today) to £12 (about £180). But, slowly, they improved. The ropey batteries were replaced by lithium-ion rechargeable ones which lasted for days; the clunky bakelite grips became moulded and stylish. Although there was still no evidence that these things were actually any better for your teeth than a bog-standard toothbrush, an ever more oral-health-conscious population was increasingly willing to pay for them.

One key turning point came in 1987, when David Giuliani, an American electrical engineer, met two professors of dentistry at the University of Washington. Five years of experiments later they released the Sonicare toothbrush; it had a piezoelectric motor which allowed its head to vibrate far faster than older models and used a contactless inductive-coil charging system.

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That triggered the start of the Toothbrush Wars. Sonicare was bought up by the Dutch multinational Phillips in 2000; by 2001 it was the top-selling electric toothbrush in the US. In 2005, the pharmaceutical giant Procter & Gamble bought Gillette, which included Oral-B, Sonicare’s main rival. Those two behemoths poured millions into research and development for their products. Suddenly, a toothbrush was no longer simply a means of cleaning your teeth, but a high-tech, precision-engineered accessory. Like the Gillette razors with six blades, ergonomically designed handle and soothing balm strip, each model brought with it new innovations – raising the high water mark for oral hygiene each time.


Some of the innovations were simple: a timer to let you know when your recommended two minutes of brushing were up; a light to let you know that it was charging. Others were more dramatic: “ultrasonic” heads which vibrate at higher frequencies than the human ear can hear; sensors that detect brushing habits. Oral-B and Sonicare steadily came to dominate the market – two-thirds of all money spent, worldwide, on electric toothbrushes goes to one or other of the two giants. And to keep the custom coming in, they brought out a dizzying profusion of toothbrushes.

Now, there are 41 different electric toothbrush options on the Oral-B website alone – some of which are different colours of the same essential kit (staid “black” versus exciting “anthracite grey”, for instance), but many of which have different features. They range in value from the Vitality Plus, which you can get for less than £20, to the all-singing, all-dancing Genius X Limited Edition with Artificial Intelligence (really), which will set you back £340. At the time of writing, Oral-B’s main rival, Philips Sonicare, offers the CleanCare+ for £18, the DiamondClean Smart for a rather steeper £299.99, and a wide variety of options in between. The high-end options are, of course, Bluetooth® enabled. The industry is worth – depending on which market report you believe – between £1 billion and £2 billion a year, and is projected to keep on growing. As developing economies grow and gain disposable income, more and more people in once-poorer countries are buying them.

But in the end, they’re still toothbrushes. They still have a single goal: to make your teeth and gums healthier. The question is: do they work?

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The membrane between science and marketing has always been porous. Doctors recommended Camel cigarettes in the 1950s and 1960s. (Dentists, meanwhile, recommended Viceroys, at least according to Viceroy.) Nine out of ten women found their hair was glossier when they used this particular brand of shampoo! Buy our overpriced skin cream, it contains hydrolysed X-microprotein nutricomplexes!

That’s true in dental care as well. In the 1930s, long before electric toothbrushes were anything more than a novelty, the Electro Massage Tooth Brush Company promised its new high-tech machine would correct “sluggish, deficient circulation, the cause of so many gum disorders”. For the record, sluggish, deficient circulation is not the cause of any gum disorders.

Britons have a reputation for having dreadful teeth, and until quite recently, it was entirely deserved. That 1969 Which? article said, in its opening paragraph, that “by the time they sit down to eat their twenty-first birthday cake, about one-sixth of the nation’s youth are wearing full or partial dentures”; by the age of 45, that figure rose to two-thirds. At least until the birth of the NHS, says Bairsto, most people would only go to the dentist when they were in pain. The growth in understanding of how oral bacteria form plaque and how the various species of those bacteria are linked to gingivitis and cavities has led to a vast improvement, through new products such as fluoridated toothpaste, improvements in brushing technique, and better dentistry. “It’s staggering how much our oral health has improved,” says Bairsto. “In a relatively short space of time.”

Research into electric toothbrushes, however, was scarcer. That 1969 Which? article mentions a two-year study published by the University of Dundee dental school in 1968, which found no advantage for electric toothbrushes over manual ones, although Which? did add that children found them more fun and disabled people found them easier, so they might improve brushing habits in those groups.

In the years after that, research did pick up. The trouble is that, unlike the Dundee study, most of the research has been carried out by pharmaceutical companies who themselves make electric toothbrushes. There’s nothing insidious about this: the companies would do the research themselves, or they would offer money to university departments or individual scholars to support research, which is entirely above board. One of the authors quoted in this piece was punctilious in declaring an interest, by saying that he did one piece of research a few years ago which was funded by a major toothbrush manufacturer. But there is good evidence that studies with financial conflicts of interest are more likely to return positive results.

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However, that doesn’t mean there is no good research. Peter Robinson, head of the School of Oral and Dental Sciences at the University of Bristol, worked – along with many other scientists – on some major reviews of the scientific literature by the respected Cochrane Library. “I got involved about 20 years ago,” he says. The first was in 2003; the latest was 2014.

The reviews looked at the benefits of “powered vs manual toothbrushing for oral health”. (They call them powered toothbrushes, rather than electric toothbrushes as the rest of us do. “We call them powered,” says Robinson, wearily, “because we do.”)

The Cochrane reviews took all of the available research on the topic, tried to tease out the good, unbiased studies, and combined them to make, in essence, one large, extra-powerful super-study, a “meta-analysis”. Damian Walmsley, a professor at the University of Birmingham’s School of Dentistry who also worked on the reviews, says they took steps to avoid most of the obvious pitfalls of biased science. For instance, negative studies might simply not be published – the so-called “desk drawer” problem, or publication bias, meaning that the scientific literature tends to fill up with positive results. Walmsley says Cochrane relies on studies that were registered in advance, so they know they aren’t being hidden. They also go and ask for stuff that didn’t make it to publication, the “grey data”. “Say if there was an abstract at a conference but the paper never materialised,” says Walmsley. “We’d write to the companies and ask for the data, and most of them obliged.” Three such unpublished studies are quoted in the review.

It’s impossible to entirely eliminate bias, and Sue Pavitt, a professor of dental public health at the University of Leeds, points out that of the 56 trials looked at in the latest Cochrane, only five were declared at “low” risk of bias. (Five were discounted because of their “high” risk, and the other 46 were “unclear”.) What’s more, they’re small: “There were 4,624 partipants in those 51. If you divide 4,624 by 51, you see that the average size is small on the whole.” Along with the potential for bias, she says, “that sets up some concerns”.

All that said, the Cochrane reviews are pretty clear. They looked at plaque buildup and gingivitis (gum disease), finding that electric toothbrushes were, on average, more effective than manual ones. The effects were real. An average 11 per cent reduction in the degree of plaque buildup, in the short term, and a 21 per cent over three months term; a six per cent or 11 per cent reduction in gingivitis, depending on how you measure it. It’s well established that gingivitis, if left untreated, leads to the more serious periodontitis, when the gums pull away from the teeth, the bone around the teeth becomes damaged, and the teeth can become loose or fall out. By the time the most recent Cochrane review was published, in 2014, it was obvious that the benefits are real.

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That doesn’t help you decide which toothbrush to buy, though. Do you need the AI-enabled £300 one or will the bog-standard £20 vibrating stick with a battery in it do the job? The research here is more sparse. In 2010 Cochrane did a separate review looking at different kinds of electric toothbrush – it found that rotation-oscillation heads, such as those made by Oral-B, have some benefit over the side-to-side ones that Philips make, which implies that the actual toothbrush itself matters, not just how it changes users’ behaviour. But they were unsure about it, because there weren’t many studies – “the difference was small and its clinical importance unclear”, the study said – and there’s not much in the way of research showing that, say, UV-sterilised heads or cross-action bristles offer any improvement.

But all these innovations could be a good thing if they get more people to brush their teeth for the recommended two minutes a day. A modern electric toothbrush, says Weijden, “is essentially able to remove all the visible plaque. So the limitation is not the toothbrush, but the user.” In short, using a bog-standard £20 electric toothbrush, properly, for two minutes twice a day, is probably a bit better than using a manual toothbrush, properly, for two minutes twice a day. But the more expensive ones might make you a bit more likely to use them properly, for two minutes twice a day, and that matters too.

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It’s easy to be cynical about toothbrush manufacturers. And it’s justifiable, to some degree, to assume that innovations are led as much by market pressures as by clinical need. Tim Harford, the economist and presenter of the BBC’s More or Less, points out that one such market pressure is price discrimination. P&G and Philips want you to pay £300 for a toothbrush, he says, but if you can’t or won’t pay that much, they’d rather you spent £20 than nothing at all. You want each customer to pay as much as they are willing to pay.

But you can’t simply put two identical toothbrushes next to each other, one with a price tag of £300 and one with a price of £20, and expect rich people to buy the former. “Even if you’re a billionaire, if there’s a £20 option and a £300 option and they’re identical, you may as well go for the £20,” says Harford. So they try to find out how much you’re willing to pay, by releasing several versions with different options. If you’re extremely price-sensitive, you will stick to the no-frills £20 option; if you are willing to splash the cash, the fancy artificially intelligent versions with smartphone control and personalised brushing programmes give you an excuse to do so.

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There is, of course, nothing wrong with charging more for higher-end products. “If the patient knows how to use the toothbrush properly, then they could get the same [oral health] benefit from a less expensive one,” says van der Weijden. “But the same is true of of a car: it’ll get you from A to B whether you buy a Toyota or a Mercedes.” He also points out that a lot of the innovations are expensive to develop and run – Oral-B, he says, has a full-time team working on its smartphone app.

That said, Richard Watt, a professor of dental public health at University College London, points out that oral health (like most health issues) is strongly linked to inequality. “In the last 20 to 40 years,” he says, “the UK population’s mouths have become much cleaner, and their oral health is better. But there are always socioeconomic inequalities; poorer, less educated people brush less often and less effectively and have more periodontal disease.”

And Watt says that while studies of effectiveness have been carried out, there have been none that he is aware of into cost-effectiveness. If you spend £50 on an electric toothbrush instead of £1.50 on a manual, that is £48.50 that you can’t spend on food for your family, and even from an oral health point of view it may be that the £48.50 will do more good there. “I’d be astounded if there are studies into cost-effectiveness,” he says, and none of the other researchers are aware of any. “We need to be very cautious about advertising and hype,” he says. “There are commercial pressures to maximise profit.”

The product designers at the companies involved acknowledge that the direct advantages of a £300 toothbrush over a £20 one are less than those of a £20 over a manual, but they say that there are still reasons to buy it. Berkay Bircan, one of the product developers at Philips Sonicare, says “the clinical benefits might get less and less, but a more fancy one might motivate you to do two minutes or three minutes.”

The question is where to go next. Apps that track behaviour and sensors that check you’ve brushed every tooth are already in place; how much more high-tech can toothbrushes get? How much more advantage can be squeezed from them?

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One possibility is raising the stakes. There have been hints that periodontal disease is linked to wider health problems – sufferers are more susceptible to stroke, to heart attacks, to blocked arteries, to high blood pressure, and to cancer. Bircan mentions that they’re tracking users over long periods “to see the impact not just on their oral health but on their lives”; his colleague Greg Goddard says that “awareness of their oral health leads to a cascade of awareness of their health more generally”.

Whether this is a real effect is hard to be sure, though. It’s hard to tease out the causal link – perhaps other factors such as diet or smoking affect both oral health and general health. Van der Weijden says he is “not a strong believer” in the idea that gingivitis raises your risk of heart disease, although he acknowledges the possibility.

Another is continuing to improve, and that seems to be where the developers are going. Van der Weijden says he “dreams” of a toothbrush that, in essence, does the job of a dental hygienist but in your bathroom. “My dream would be that when you’ve brushed your teeth, your toothbrush has a camera that checks whether you’ve cleaned the surfaces adequately,” he says. “It would tell you to go back and redo those surfaces.”

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All the dentists quoted in this piece agreed that the really important thing is to brush twice a day, for two minutes each time, with good technique (“Brush them like this! *Chicki-chicki-chicki-chah!* Every single tooth!”). If you find that a £340 robobrush helps you do that, and you have the cash lying around, great. On average, you’ll do better if you use an electric toothbrush than if you don’t, although if you’re struggling for cash you might be better buying a £1.50 manual and spending the balance on healthy food or a gym membership.

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The dentists mainly agreed, too, that the gizmos and innovations that get stuck on to the higher-end versions probably aren’t a bad thing. Sue Pavitt says that she gave an electric toothbrush to her 89-year-old mother, who has mobility issues, and saw an improvement in plaque levels; she thinks that the versions that have a Disney character or a song playing probably make it easier for children to manage the full two minutes; she herself has one that not only has a timer, but goes “vrrp” every 30 seconds to tell you when you’ve done a quarter of your mouth.

The phenomenal growth of the electric toothbrush industry isn’t just about the whirring, buzzing, product at its heart – but how it changes how we treat our mouths. “It’s a gizmo but it’s a useful gizmo,” she says. “Toothbrushing is all about changing behaviours.”

Bristol University’s Peter Robinson says that in the process of doing the Cochrane review, he went on something of a journey, from a starting point of an electric-toothbrush sceptic. He describes himself as being a “late adopter” of technology, and having gone into the job “thinking global pharma was the devil”. “Nevertheless,” he says, “having done the first review I immediately went out and bought an electric toothbrush.”

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