The current trend in high-end electric toothbrushes is for technology that feeds back as you brush.

Take Oral-B’s iO 9. Not only does it have a pressure sensor that’ll let you know if you’re brushing too hard and a countdown timer to show how long you have left of your dentist-recommended two-minute cleaning time, but its app will give you more detailed feedback. (Plus, the OLED screen on the brush handle will respond to you with a smiley or sad face, depending on how well you’ve brushed.)

Open the Oral-B app and you’ll get real-time information about how long you’ve brushed each section of the mouth and which areas you might be neglecting. It’s reasonably effective and will certainly help encourage better brushing from people who tend to zone out, or who often get a ticking-off from their hygienist.

Up until now, Philips hadn’t quite nailed the smart functionality of its brushes in quite the same way. The previous flagship brush, the DiamondClean 9000, has excellent performance and adjustable settings that let you choose exactly the pressure you want, but the app doesn’t feel central to the way it works. It largely exists to log brushing sessions and to allow for easy re-ordering of brush heads and other accessories.

Sonicare 9900 Prestige features

However, the new Philips brush, the Sonicare 9900 Prestige, may change all of that. Not only will it offer brushing guidance but the brush itself will respond if you are in danger of damaging your gums.

If you press too hard using the 9900 Prestige, it won’t just alert you to the fact you’re doing so, it’ll adjust the intensity so that you don’t over-brush.

It also uses sensors to monitor how hard you press when brushing and the motions you use, as well as gathering information on how long and how often you brush. When you log into the AI-driven app, it will show you your stats and offer guidance as to how to improve your brushing performance.


Among the things we liked most about the DiamondClean 9000 were its well-designed accessories, including a sleek travel case with an inbuilt USB-C charging port. It looks as though Philips has upped the ante on the 9900 Prestige, with an even more plush travel case (also with USB charging).

Another plus is that the new brush comes with an all-in-one brush head that’s good for plaque, stains and gum care. Previously, Philips had encouraged the use of different brush heads for different forms of oral care. This obviously means buying more brush heads as well as the faff of changing them over, which we weren’t too keen on.

Price and release

The 9900 Prestige will retail at £299, which is something of a surprise, given that the DiamondClean 9000 is currently priced at £340 on the Philips site, although you can buy it for £249.97 from Amazon. It'll be available from April 2021.

We’ll have to wait until we get a chance to review it to see if the app lives up to its promise. In the meantime, for more information on high-end electric toothbrushes, read our reviews of the Oral B iO, the Philips Sonicare DiamondClean 9000 or check out all of the best electric toothbrushes we’ve tested.