Dentist U. P. Saxer:
«The hydrodynamic effect is like a mountain stream»

Together with CURAPROX, Prof. Saxer has now developed a brush head that exploits the benefits of sonic technology even more. Prof. Saxer will continue to drive research projects to make sonic toothbrushes even better still.

Dentist U. P. Saxer: «The hydrodynamic effect is like a mountain stream»

Prof. Saxer, as a co-initiator of the “Sonic Hydrodynamics’ Taskforce” you have dealt intensively with sonic toothbrushes. What are the benefits of sonic toothbrushes compared to manual toothbrushes?
Prof. Saxer: No matter how soft a manual toothbrush is: many people exert so much pressure on their teeth and gums that cleaning damage is inevitable. Cleaning properly with a manual toothbrush takes a long time to learn. Even many dental professionals are unable to do this properly. On the other hand, sonic toothbrushes are extremely easy to use: simply hold it against the tooth without any pressure at all. No movement is needed; the sonic toothbrush does nearly everything itself. The risk of damage is almost zero and the teeth and gum line are cleaned efficiently, safely and effectively.

There are also electric toothbrushes with oscillating bristles. What do you think of them? How do they differ from sonic toothbrushes?
Dentists use rotating cup brushes for professional cleaning or polishing. They take care not to damage the gum. This is why the small rotary heads on standard electromechanical toothbrushes use oscillating back-and-forth movements. In comparison to rotating brushes, this significantly reduces the risk of damaging the teeth. The cleaning effect of this type of toothbrush is extremely efficient. However, the potential for damage is substantial, particularly when users exert too much pressure or brush too frequently or for too long. This results in damage to the gums and the necks of the teeth. Sonic toothbrushes do not have the same risk as their oscillations diminish when pressure is used. The benefit of sonic toothbrushes is that they not only clean mechanically, but also have an additional hydrodynamic cleaning effect. The bristles force saliva into gaps and between the teeth where bristles cannot reach.

What is the hydrodynamic effect?
The hydrodynamic effect is like a mountain stream. This can be envisioned as follows: in the mouth, a mixture of saliva, water and toothpaste is created while brushing and, from this mixture, a sonic toothbrush makes a wild mountain stream, so to speak, with many rapids and falls. Because of its more than 30,000 oscillations per minute, a sonic toothbrush generates powerful turbulences in this mixture of saliva, water and toothpaste. This turbulence ensures that the mixture also hits the plaque between the teeth at a very high speed. The plaque is swept away even where the bristles do not reach at all. Sonic toothbrushes clean not only where the bristles are, but also where the mixture of saliva, water and toothpaste is propelled. This is very tough on the plaque, but very gentle on teeth and gums.

What is special about a CURAPROX Hydrosonic?
“Hydrosonic” is an abbreviation of “hydrodynamic sonic toothbrush” and a CURAPROX Hydrosonic bears this name for good reason: it has a very strong motor and thus a very high frequency. With this, the hydrodynamic effect can be utilized to the full. Moreover, a CURAPROX Hydrosonic has a hydro power brush head with special bristles, and these bristles are arranged in such a way that they boost the hydrodynamic effect: the mixture of saliva, water and toothpaste can destroy plaque on implants, between the teeth and under braces particularly well. At the same time, the brush head also has higher tufts of bristles. This ensures that the distance between the tooth surface and the bristles is sufficiently large. These shorter bristles can oscillate freely and provide the desired hydrodynamic effect of the saliva while the longer bristles slip into the niches and interdental spaces, giving any plaque no chance against more than 30,000 oscillations per minute.

And what is special about the bristles?
The bristles on most other sonic toothbrushes, even those in the upper price range, are made from nylon. Nylon is relatively soft and even absorbs water. However, the bristles on a CURAPROX Hydrosonic are made of CUREN® and, thanks to this material, they are considerably stiffer and thus springier. This firmness permits the force that a Hydrosonic develops to be transferred entirely into the mixture of saliva, water and toothpaste. This is ideal for the hydrodynamic effect. CUREN® bristles also do not absorb water and their firmness and springiness are also maintained in the wet state. This is especially important for the hydrodynamic effect because the oscillation is transmitted to the mixture of saliva, water and toothpaste with virtually no loss. The force developed by this mixture is thus very strong and, at the same time, the mixture is very gentle on teeth and gums.

What are the indentations in the hand part of the CURAPROX Hydrosonic for?
These indentations help users to hold a Hydrosonic at the right angle. It is important to place a sonic toothbrush at a 45-degree angle and hold it to the gums so that half of the bristles are on the teeth and the other half sit gently on the gum. Imagine holding it like a violin bow, quite steadily, without pressure and with almost no movement. This position ensures that the gum line and any periodontal pockets are cleaned. These indentations on a CURAPROX Hydrosonic thus help users to clean their teeth properly. It is very simple, but extremely helpful.

Can this cleaning technology be learned quite quickly?
Yes, and beginners can start by cleaning at a reverse 45-degree angle: they can hold a sonic toothbrush away from the gums, rather than against the gums. This helps many beginners to get used to the light tickle of a sonic toothbrush. I discovered this trick later on; otherwise, I would probably have become a fan of sonic toothbrushes immediately. More advanced users hold their CURAPROX Hydrosonic to the gums and let the brush simply work on the tooth for a few seconds before moving on to the next tooth. A slightly tilting motion is also recommended so that the bristles still reach a little further into the interdental spaces. But only one tilting motion forwards, quite gently and then backwards, quite slowly.

Who is a CURAPROX Hydrosonic suitable for?
A CURAPROX Hydrosonic is suitable for anyone who wants to make sure that they clean their teeth really well, even for children and young people. It is also helpful for people with implants or braces. These must be cleaned in all their niches exceptionally well and the best, safest and easiest way is with a sonic toothbrush, particularly with a CURAPROX Hydrosonic.

Interdental brushes are included with the CURAPROX Hydrosonic. Why?
Another advantage of sonic toothbrushes is the following: thanks to their hydrodynamic effect, they also clean the interdental spaces if they are used first on the inside and then the outside. A CURAPROX Hydrosonic does this particularly well. Plaque can still form between the teeth because there are always small niches that are almost impossible to reach even with the best sonic toothbrush and in spite of the hydrodynamic effect. People who want to eliminate tooth decay or gingivitis will do well to clean their interdental spaces professionally. This is particularly valid for those older than 30 or already suffering from gingivitis or even periodontitis or caries. So, once daily, best of all in the evening, clean the interdental spaces before brushing the teeth. And this works best of all with CPS prime, interdental brushes, which are also used by dental professionals. They are available in different dimensions. The interdental brushes that are included are to be understood as testers; and they should only be used once. Go to for full instructions. When inserted, the brush should not hurt. However, it should not simply slip through the interdental spaces. One should feel it properly. And then, once in and out is sufficient. It is important to consult a dentist or dental hygienist and have the correct size for each interdental space identified. It takes a bit of effort at the beginning to make sure that the right brushes are being used.

And the toothpaste included?
CURAPROX enzycal is one of the few toothpastes that do not contain any sodium lauryl sulphate, so no SLS. It does not foam as strongly and binds less to the surfaces of teeth and mucosa. This makes the toothpaste sonic toothbrush-friendly: the mixture of saliva, water and toothpaste remains fluid, which is good for the hydrodynamic effect. For the same reason, since CURAPROX enzycal dispenses with SLS, it does not irritate but actually strengthens the oral mucosa. CURAPROX enzycal is truly worth recommending.

Does this mean that a CURAPROX Hydrosonic is a complete oral health set?
Yes, a CURAPROX Hydrosonic includes the best tools for the ideal care of the teeth, gums, tongue and mucous membranes.

Thank you, Prof. Saxer.

Prof. Dr. med. dent. Ueli P. Saxer is the founder of the first School for Dental Hygienists in Switzerland and Director of the Prophylaxis Center Zurich (PZZ). Since 1993, he has been following the development of sonic toothbrushes. He himself took a while to come round to the advantages of this new technology: for some years, he alternated between using a manual toothbrush and a sonic toothbrush before his enthusiasm was kindled.

At the suggestion of his daughter, Dr. med. dent. Claudia M. Saxer, who is a dentist for children and young people, Prof. Saxer founded the “Sonic Hydrodynamics’ Taskforce” initiative in 2008 together with Prof. Dr. med. dent. Thomas Imfeld and Dr. med. dent. Hubertus van Waes. This taskforce campaigned for a quality seal for hydrodynamic brushes.