Emmi-dent is a German company and the Professional 6 claims to be the first consumer tooth brush to use ultrasound to clean teeth.

The benefits of this are supposedly to avoid as much abrasion as possible and thereby reduce damage to gums and enamel.

The toothbrush feels a bit bulky and plasticy and the detachable head (two are supplied) resembles a traditional toothbrush. Turning it on sees the head vibrate ever so softly and at first one wonders if it's doing anything at all. Indeed, if you're someone who refuses to read instructions and expects the Professional 6 to behave like Braun's mechanical toothbrush or Philip's Sonicare range, you won't think it does anything - it's like a regular toothbrush that vibrates a bit. But persevere.

You really are supposed to just press it lightly to your teeth and gums and simply leave it there. The head bristles are almost just for show: the real magic happens by the ultrasound creating nanobubbles around your teeth and it's these that do the cleaning. Most importantly, they do a very good job.

Whereas traditional, mechanical and Sonicare toothbrushes recommend two-minutes for cleaning, however, Emmi-dent recommends three to five. This is to allow the toothbrush to rest in place for three to four seconds in all positions around the mouth. In practice it felt like it did a fine job after two minutes. But then Philips' excellent Sonicare range feels like it can do a good job much quicker.

Emmi-dent recommends using its own toothpaste and a small tube comes with it. Regular toothpaste works too, but isn't as good at creating nanobubbles.

After a unimpressive start, we really grew to love the Professional 6. It's no good for a rapid, "I have 10 seconds to clean my teeth on the way out the door" scenarios, although you can use it as a traditional toothbrush on those occasions. Basically, the Professional 6 can't easily be rushed - this is a good thing for people who do rush and have a tendancy to rub their gums away. The rechargeable battery lasts for three weeks so it's fine for travelling.

Elsewhere, Philips' Sonicare system is probably still our favourite, offering ultrasonic-like cleaning with a mild but rapid abrasive action too. The range also includes cool features like a USB-rechargable travel case, UV bacteria cleaning chamber and inductive (wireless) charging stations. Prices range from around $100 for a simple toothbrush to $250(ish) for one with all the trimmings. While it seems expensive, not investing in your teeth can be the epitome of false economy.

Meanwhile, the Emmi-dent will suit those with ultra-sensitive mouths, those who simply can't withstand any serious abrasive action and those who spend considerable time cleaning their teeth. The toothpaste refills are relatively-inexpensive at less-than $10 per tube (you only need a small amount) however, at $235 for the system it's mighty expensive. The Philips is more-widely available and, ahem, longer in the tooth so can be had cheaper, but ultimately, this can be said to do a similar job in a different way. While we're no dentists, after thirty years of oral hygeine, we know when our teeth are clean and this gets 'em that way. Nonetheless, both systems are well recommended by dentists, so the industry backing is there too.