Believe it or not, the first electric toothbrush was presented in Harper’s Weekly on February 13th in 1886. But a true milestone in the world of home dental care is considered to be the invention of the first high-frequency sonic toothbrush – the Sonicare, by the Optiva Corporation – which was presented at the Chicago Midwinter Meeting in January 1993, nearly 30 years ago. However, in fact, the first real electric and sonic toothbrush was the Broxodent, conceived in Geneva, Switzerland in 1954 by Dr. Philippe-Guy Woog, and presented in 1959 by Squibb Pharmaceuticals at the Centennial Congress of the American Dental Association in the USA.
While a mechanical toothbrush is still the most popular standard for home dental care, and electrical toothbrushes were initially recommended for people with disabilities and children, sonic technology is now one of the most efficient and valued technologies in the oral-care world.
According to a 2019 SHIP cohort study carried out over 11 years, using an electric toothbrush prevents tooth loss. The study found that people using a powered toothbrush experienced less attachment loss, which after their 11‐year follow‐up resulted in an average of 0.36 more teeth for electric brush users than those of their manual-toothbrush using counterparts.
One of the most important people in the development of such innovative and helpful products, such as Curaprox’s Hydrosonic pro, is the renowned Professor Ulrich P. Saxer, an expert in the field of gingivitis, periodontitis and peri-implantitis management – with both mechanical and chemical agents. Here are his answers to the key questions about sonic toothbrushes, that dental professionals around the world can confidently communicate to their patients.
Prof. Dr. Ulrich P. Saxer completed his studies in dentistry in Zurich, Switzerland in 1967, and specialised in periodontology and oral prevention early in his professional career. He is a former owner of a dental hygiene school in Zurich, and has helped set up four dental hygiene schools in Geneva, Bern and Zurich – institutions that educate a new generation of highly qualified oral health professionals devoted to prevention. Prof. Saxer has conducted over 120 lectures in Europe and the USA, and published 150 scientific papers. He is a key opinion leader in the field of oral prophylaxis, and was scientific advisor for the development of the latest generation of sonic toothbrushes made by Curaden AG. For many years, professor Saxer was a member of the board of Toothfriendly International – an international non-profit organisation working for better oral health.
The secret behind the easy yet highly effective cleaning of sonic brushes lies in the hydrodynamic effect. It has been proven that toothbrushes with over 60,000 movements per minute are capable of cleaning in two different ways. The first is mechanical, by direct contact of the bristles with the tooth, and the second is thanks to the hydrodynamic force that works bristles without even touching the surface of teeth and gums. It has been shown that removal of bacteria in gingival pockets up to 6 mm is possible thanks to the hydrodynamic effect. How can we explain the hydrodynamic effect to patients in a comprehensible way?
Try explaining the hydrodynamic effect to patients by comparing it to nature. When you brush your teeth, a mixture of saliva, water and toothpaste is created, and the sonic toothbrush turns this mixture into a wild mountain stream with many rapids and falls, or maybe even better – into a gentle tsunami.
“Sonic toothbrushes are extremely easy to use even for kids or patients with orthodontic appliances or suffering from any form of motor disability.”
With over 60,000 movements per minute, the sonic toothbrush generates incredibly strong turbulence in the above-mentioned mixture. This turbulence then ensures that the mixture shoots over and between all the tooth surfaces at high speed. Thanks to this, plaque is removed even from spaces where the bristles cannot reach. Sonic toothbrushes don’t only clean where the bristles go, but also where this saliva-water-toothpaste mixture is thrown. This is very effective against biofilm, but at the same time, very gentle on the teeth and gums.
The first animation (below) shows the removal of marginal plaque – where the biofilm first starts to grow – with a single tufted brush, while the second animation demonstrates the hydrodynamic effects of the Hydrosonic toothbrush. Unfortunately, it is not really possible to show the full range of the hydrodynamic effect of sonic toothbrushes, because their main strength lies in the precise cooperation of longer and shorter bristles. The longer outer bristles mainly clean mechanically, and they move across the tooth surface with the help of just slight pressure whilst the brush is moved manually. On the other hand, the inner shortened bristles do not touch the tooth surface at all, and thanks to the fact that these bristles are not hindered in their movement, they create a targeted hydrodynamic effect in the direction of the tooth, and thus clean mainly recesses, interdental spaces, or niches that are created, for example, by braces.
Why are sonic toothbrushes preferred over oscillating toothbrushes?
The main differences between a sonic and oscillating toothbrush are the direction of the brushes’ movements, the shape of the brush heads and the cleaning coverage. Oscillating toothbrushes do not reach the interdental spaces, and the turbulence they create is directed mainly to the sides. The vibrations present in sonic technology, on the other hand, have the power to reach interdental spaces due to the hydrodynamic effect.
The overall cleaning impact on gum health – removing bacteria out of pockets and thus reducing inflammation – is therefore, according to studies, more effective with sonic toothbrushes. The sulcus area, the transition point between the teeth and the gum, is sometimes neglected. The special thing is that with sonic brushes you can feel the entire surface of the teeth right to the edge of the gums. If the gum line is cleaned a little, it is still safe, because the bristles are very fine and comfortable and the movements of sonic toothbrushes are side-to-side, which leads to almost no injuries. An oscillating movement in toothbrushes is often destructive. But the Curaden’s Hydrosonic toothbrushes have much softer filaments than the oscillating toothbrushes, and also other sonic toothbrushes.
It should be noted that not all circular movement-based dental procedures are bad. Patients should be aware that dentists also perform rotating movements with their cleaning instruments – but this is very different. They can fully control the movement as they have an optimal view of the tooth, and whilst they use circular movements, it is not strictly oscillating.
When patients are cleaning their own teeth, however, they do not have a chance to observe exactly what the brush is doing on the tooth surface because they are missing the optimal view, and that can lead to gum injuries.
In addition, the Hydrosonic pro toothbrush has the special drop shape of the brush head. Thanks to this, it is easy for patients to optimally adapt their toothbrush to the tooth surfaces both buccally and orally – on the side and in the front. This is possible thanks to the angulation of the brush, the shape, and also the rubberised back of the handle. Other sonic toothbrush manufacturers make the brush handles from a solid hard plastic material, so that the energy from the motor can be perfectly transferred to the brush. When vibrating, this hard handle can cause unpleasant feelings, frighten the user or even hurt the mouth. All those uncomfortable risks are lowered to the minimum with the Hydrosonic pro’s special bristles and design.
What is the main advantage of sonic toothbrushes over manual toothbrushes?
Many people put too much pressure on their teeth and gums when using manual brushes, which means that cleaning damage is inevitable. This is especially the case with hard-bristled brushes. Over time, this can lead to receding gums, destroyed enamel and gum injuries.
Learning the proper cleaning technique with a manual toothbrush takes time and practice, and unfortunately, is not suitable for many patients with certain limitations of movement. Sonic toothbrushes, on the other hand, are extremely easy to use – even for kids or patients with braces or implants. In fact, they’re ideal for anyone who wears orthodontic appliances, or suffers from any form of motor disability.
“It is important to remember that the mouth should be closed during a cleaning with a sonic toothbrush.”
Since braces are usually equipped with wire parts and hooks, the vibration and movement of the bristles on a sonic brush, combined with the hydrodynamic effect, makes it easier to ensure a thorough clean. Some of the bristles will stay on the braces themselves, whilst the vibration of the neighbouring bristles means they have a greater freedom to reach into the gaps and surfaces around the braces, resulting in an enhanced clean.
It is important to remember that with a sonic toothbrush you brush without using forced pressure. The Hydrosonic toothbrush should be guided and well applied to the tooth with light pressure of only approx. 30-40 pond. For cleaning, it is advisable not to rest the brush completely on the tooth, but to make small circular movements almost in the same place, so that all parts of the tooth benefit from the bristles touching the tooth (mechanical cleaning), and at the same time from the freely oscillating bristles (hydrodynamic cleaning). A 45-degree inclination to the tooth helps clean in the sulcus in particular, which is indicated in gingivitis and periodontitis. The 90-degree brush position has a full effect on the tooth, so the best cleaning of the tooth surface and the interdental spaces is achieved this way. It is important to remember that the mouth should be closed during a cleaning with a sonic toothbrush.
The sonic toothbrush does almost all the work for you. When you choose the right brush with gentle filaments, the teeth are cleaned efficiently, safely and effectively.
When talking to patients about the Hydrosonic pro, what are the most important features of the product that they should be aware of?
The Curaprox Hydrosonic pro has a very powerful motor, so it can provide an extremely high number of movements per minute. Thanks to this, the hydrodynamic effect can be fully utilised. In addition, the special ultra-soft bristles, and the way these bristles are arranged, combine to strengthen the hydrodynamic effect further. The saliva-water-toothpaste mixture it creates can remove the plaque biofilm even on implants and to some extent between the teeth (with 90-degree angulation), and it works particularly well around braces and in the spaces of the gingival sulcus (with 45-degree angulation).
Areas like interdental spaces and the sulcus are the most critical when talking about proper oral hygiene. The possibility of using the single brush head is also extremely helpful when cleaning these critical places, and one of the most important advantages of the product is the super-gentle bristles of the brushes, since this is the key element when talking about safe cleaning – especially in brushes with such high frequencies.
The bristles on the Hydrosonic pro’s brush heads are arranged in a drop-shape, to more effectively clean the hidden surfaces and spaces of the teeth. And last but definitely not least, is the brush heads’ built-in Curacurve® angle of only 10 or 15 degrees, which makes a big difference when it comes to accessing molars or other hard-to-reach spots.
Why is the quality and quantity of the bristles so important when it comes to a toothbrush?
The bristles of the Hydrosonic pro are made of Curen® filaments, which is why they are so soft yet still able to maintain their rigidity. Curen® filaments do not absorb water, and so their rigidity and effectiveness are retained even when wet. This is particularly important for the hydrodynamic effect. At the same time, their softness ensures they are very gentle on teeth and gums.
Also important for the effectivity of the hydrodynamic effect is proximity. This is why the brush head has raised tufts of bristles – to ensure that the distance between the tooth surface and the vibrating bristles is sufficiently large. Shorter bristles can then vibrate freely and provide the desired hydrodynamic effect, while the longer bristles slip into the niches and interdental spaces. This combined with over 60,000 movements per minute, means plaque, bacteria and biofilm hardly have a chance.
The brush’s settings have the power to prevent teeth discolouration and also to practically rule out tartar growth. This interplay of bristles and their arrangement must be precisely and finely tuned. To make the brush even more gentle, the bristles are rounded. Not every manufacturer of sonic toothbrushes has designed this equally well.
For patients, one of the easiest and most visible ways to observe the quality of a sonic toothbrush is to look at the brush carefully before using it for the first time, and to examine their teeth at the niches and recesses for any slight discolouration. This discolouration will be gone after two to six days of using a proper sonic toothbrush.
The angled brush head of the Hydrosonic pro isn’t common in other sonic brushes. Why have you decided to apply such an approach when developing this toothbrush?
The decision concerning the angling of the brush head has been made very deliberately – despite the knowledge that this results in a changed dynamic on the bristle tips. It was important for us that all parts of the mouth can be reached.
For example, at the very back, the teeth are aligned. The built-in angle in the handle allows these areas to be reached more easily – which, by the way, has also been scientifically investigated. When you think about it, only a few dental instruments are straight! The angulation is also important for the accessibility of the teeth at the front in the outer and inner mouth area. The Hydrosonic pro meets these requirements, so patients won’t miss a single spot in their mouth that needs to be cleaned properly.
What about abrasion and sensitivity of the tooth necks? These are often concerns when it comes to sonic toothbrushes.
The Hydrosonic pro toothbrush naturally cleans with a much higher number of movements than the classic manual brush. One might assume that this leads to worn-out enamel and sensitivity of the teeth, but the opposite is true. Various studies have shown that due to the low contact pressure and the fact that most of the bristles do not touch the tooth at all, but instead clean hydrodynamically, there is only a little portion of the enamel removed from the tooth. For this reason, there is no tooth-neck sensitivity. On the contrary, it has been proven, that sonic toothbrushes reduce tooth sensitivity.
Sonic toothbrushes in brief
Answer your patients’s questions using key points from the knowledge of expert Prof. Dr. Ulrich P. Saxer.
☞ FOR WHO?
☞ WITH WHAT?
☞ HOW OFTEN?
☞ WHICH ONE?
- Schmidt JC, Astasov-Frauenhoffer M, Waltimo T, Weiger R, Walter C. Efficacy of various side-to-side toothbrushes and impact of brushing parameters on noncontact biofilm removal in an interdental space model. Clin Oral Investig. 2017 Jun;21(5):1565-1577. doi: 10.1007/s00784-016-1969-y. Epub 2016 Oct 19. PMID: 27757550.
- Pitchika V, Pink C, Völzke H, Welk A, Kocher T, Holtfreter B. Long‐term impact of powered toothbrush on oral health: 11‐year cohort study. J Clin Periodontol. 2019; 46: 713‐ 722.
- Danser MM, Timmerman MF, IJzerman Y, Bulthuis H, van der Velden U, van der Weijden GA. Evaluation of the incidence of gingival abrasion as a result of toothbrushing. J Clin Periodontol. 1998 Sep;25(9):701-6. doi: 10.1111/j.1600-051x.1998.tb02510.x. PMID: 9763324.