I used this AI-powered full-mouth toothbrush even though my dentist told me not to

(Image credit: Future)

When I first told my dentist about the Feno Smartbrush, eyebrows were raised. “Don’t use that,” she quipped as I explained the concept of Feno’s rather revolutionary approach to dental hygiene.

Despite my dentist’s protests, I’ve been hands-on with the Feno Smartbrush to glimpse the future of dentistry, my experience has left me intrigued, if not sold, and I’m excited to see how and where Feno takes brushing your teeth in the future.

My dentist’s reservations can be explained thusly: the best electric toothbrushes on the market work to agitate plaque and gums around individual teeth. A good two-minute clean usually ensures you’ve given each one a good seeing to, leaving your mouth thoroughly brushed. Feno’s Smartbrush, as you can see from the pictures, is designed to brush all of your teeth at the same time. My dentist’s concern was that the Feno doesn’t offer the dexterity of a standard electric toothbrush, making it difficult to clean individual teeth at all the right angles. It’s designed to make brushing your teeth faster, easier, and more convenient, but does that come at a cost?

This time-saving cross between a football player’s mouthguard and a power drill comes packed with tech, too. It features wireless charging, health tracking and performance data, and a camera for scanning your mouth. That data can be shared with an Oral Health Coach who can give you data-driven consultations, provide feedback, and help you get on top of issues before they get out of hand. Dental health epitomizes the adage that prevention is better than cure, and with this tool, Feno is offering a service no one else really provides.

So I took the plunge and gave Feno a whirl. Here’s what I did and didn’t love.

Connected dentistry

I love the concept of Feno as the future of connected dentistry. Getting one involves taking pictures of your mouth in order to get a custom-sized TrueFit Mouthpiece. In the generous founder's bundle you get the Smartbrush, a charger, three tubes of toothpaste, and a tongue scraper, plus three months of Feno Plus, the company’s proprietary app replete with personalized health insights and oral health coaching.

We apply tech to every other area of our lives, so why not oral hygiene? For many, myself included, visiting the dentist is often daunting, and the idea of a slightly less intrusive virtual service is really appealing. I love the thought of a future in oral hygiene where I can communicate with a dentist more regularly, getting coaching and pointers as well as monthly peace of mind, rather than a twice-yearly checkup I tend to dread.

I also love how Feno is applying the technology; the Smartbrush has a built-in scanner, Wi-Fi, and Bluetooth. It uses AI models and real dental professionals to analyze scans of your mouth to provide the feedback you get in the app. The app also features streaks, video brushing tutorials, and more.

High octane brushing

Inside your mouth, Feno is a pretty daunting experience. For the uninitiated, the mouthpiece is pretty big and not that comfortable to use. Once it’s in, you press the button and you’re off, 20 seconds of intense vibration, aided by the user agitating the brush. It’s a very strange sensation and definitely takes a while to get used to. The first couple of days yielded some bleeding, which Feno says is to be expected.

The big appeal is the time saved, and having grown used to brushing my teeth for two minutes at a time, a brushing experience that ends in 20 seconds is really strange and quite delightful. The feeling of cleanliness is undeniable, Feno says that its internal pilot studies yielded 99% plaque removal in three days, while achieving that coveted 75% reduction in brushing time. However, its disclaimers warn that outcomes may differ among the general population, and often, the efficacy of this sort of thing takes years of research and clinical study to establish. Using the Feno would certainly be better than a manual toothbrush, but whether it’s better than an electric toothbrush is impossible to say without extensive use, probably over years.

One fatal flaw

For one very specific reason, I won’t be adopting the Feno as my mainstay going forward. The toothpaste included, while rather delicious and foamy for easy application on the mouthpiece, doesn’t contain fluoride. Feno tells me this is a work in progress, but being a controlled substance, it’s not an easy addition when creating a custom formulation. That’s why Feno included xylitol; there’s some crossover in terms of the benefits.

Fluoride is pretty much standard in toothpaste and as this 2019 study notes, “Several studies have confirmed that fluoridated toothpaste is an effective method to control dental caries, and the demineralization of enamel is negatively correlated with the concentration of fluoride in toothpaste in both permanent or deciduous enamel, as well as root dentin.” Fluoride in toothpaste helps reduce demineralization of enamel, promotes re-mineralization, and inhibits the metabolism of bacteria. The American Dental Association notes the role of fluoride in preventing tooth decay, and UK government guidelines recommend its use.

If Feno can get fluoride into its toothpaste, I’ll definitely revisit its Smartbrush. There’s a lot to like here, and the tech is very impressive. I think Feno is touching on the future of smart, connected dentistry powered by at-home scans, virtual support, and brushing powered by apps and AI. The jury is still out on whether its solution is better than the best electric toothbrushes out there, but it’s definitely worth considering, especially if you’re still a manual brusher.