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Published: January 2, 2024

Megasonex M8S review

Author: Jon Love (Leave a comment)
Megasonex M8S review 1

The best ultrasonic toothbrush if you want this type of tech


Unless you are set on using an ultrasonic toothbrush, don’t buy the Megasonex M8S.

You are paying a fairly significant premium for the technology, which may only provide limited benefit over traditional sonic and oscillating rotating brushes.

Megasonex M8S
Megasonex M8S




Good battery life


No icons on the handle to show which cleaning mode is selected


Multiple cleaning modes


No pressure sensor


Ultrasonic technology


Limited benefit to ultrasound technology


Good box contents


Not widely stocked


Compact travel case


Limited warranty

Spend more wisely on these brushes

If you are set on an ultrasound toothbrush you have very limited choice. The M8S is the best option, but there is the Emmi-dent Platinum as an alternative option.

However, given the price premium and limited evidence to confirm their benefit, it is well worth considering some other options that will likely work out much more affordable.

Notably, the best electric toothbrush on the market today, the Oral-B Pro 3 3 500. You can get 3 of these for the cost of the M8S.

It functions differently, but it’s dentist approved.

How the M8S looks, feels and works

Whilst it might not look any different to a regular electric brush, it is. I want to focus first on what makes the Megasonex M8S different from other electric toothbrushes.

How the ultrasound actually works

Built inside the tip of the brush handle of the M8S is Megasonex’s proprietary 17mm Megacrystal. 

Approved by the Food and Drug Administration (FDA) in the early 1990s it operates at a safe low-power medical frequency of 1.6MHz. 

1.6MHZ = 1,600,000 Hertz (cycles per second) or 96,000,000 pulses per minute. This is similar to the frequency used by doctors to treat fractured bones. 

Typical “sonic” toothbrushes such as those from Philips Sonicare and Colgate, amongst others, typically offer 15 to 40 thousand bristle movements per minute or 125 to 333 Hertz. This is somewhere in the region of 2,400-6,400 times lower than ultrasound. 

Megasonex M8S review 2

We brush or clean our teeth to remove plaque. Plaque is formed by bacteria, fuelled by the food and drink we consume. If not removed or disrupted it can lead to all sorts of oral health issues.

Brushing breaks up and removes the plaque, which at a microscopic level is made up of bacteria formed into chains.

Ultrasound is able to break these bacterial chains and disrupt their growth, without the need for bristles. The once potentially harmful plaque is no longer.

It’s backed by scientific study

One of the earliest studies that paved the future for ultrasonic toothbrushes was conducted in 1999, by Shinda et al from the faculty of dentistry and the Tokyo medical and dental university.

This study focused on ultrasonic technology only and didn’t account for the additional benefits of sonic vibrations that are available on the Megasonex brushes. 

Teeth brushing with Megasonex toothbrush

A 2015 study by Hashizume and Dariva confirmed that a toothbrush with both sonic and ultrasonic vibrations did result in a lower bacterial count compared to ultrasonic only.

In 2018, Horiuchi and counterparts from the Tokushima University Hospital studied the effects of pulsed ultrasound. Their research found that sonic vibration with pulsed ultrasound showed a greater reduction in the biofilm than sonic vibration with and without continuous ultrasound.

It’s not necessarily time to ditch the manual or regular electric toothbrush

Although there has been study into the effects of ultrasound that would suggest benefits, more research and understanding of the impact on oral health is needed.

Digel et al looked at plaque removal by ultrasonic toothbrushes in their 2020 study and concluded.

The differences in the reduction of dental plaque by ultrasonic vs. sonic toothbrushes were not statistically significant. Both types of toothbrushes showed successful removal of plaque and reduction in gingival infection but no elimination of already existing periodontal diseases, as well as no difference in the infiltration of supra- and sub-gingival regions. The combination of both types, sonic and ultrasonic, showed the most promising result in maintaining good oral health.

Digel et al

This was essentially confirmed a year later in another piece of research by the team from Sao Paulo State University in 2021 when they looked at the effect of electric, ultrasonic and manual toothbrushes on biofilm removal and gingivitis control.

So, what they are saying here is that the combination of sonic and ultrasonic vibrations, just like the M8S offers is most promising. But, as it stands there isn’t a clear cut case to ditch the regular toothbrushes and techniques we are used to.

It can be silent in operation - 0 decibels

There are 3 cleaning modes available on the M8S.

I will cover them in more detail shortly, but the 3rd mode is ultrasound only, it offers no sonic movement like the first 2 modes.

As such, when in this mode it is silent in operation. That is right, it produces no sound and essentially registers at 0 decibels. The bristles don’t move either.

Compare this to the other modes that produce around 51 decibels when in operation.

The complication here is that, you have to press the clicky power button, which produces a sound and then at 30 second intervals the pacer kicks in, causing sound.

White M8s Ultrasound toothbrush in the hand

It’s basically impossible to know it is working

I am not questioning the science, ultrasound has been shown to work, disrupting bacterial chains.

But, to you and me as users, the ultrasound is silent in operation. Even on the modes with sonic vibration.

Unless you have an oscilloscope to measure the ultrasound it is impossible to tell if it is even functional.

In the 3rd cleaning mode of ultrasound only, if it were not for the blue light on the handle and the pulsing at 30 second intervals you wouldn’t know. You simply cannot feel or detect these vibrations. 

In part it is amazing, but in another way, it is simply weird because you just don’t know what’s going on.

As the research has already shown, there are potential benefits of ultrasonic toothbrushes like Megasonex. But they have yet to prove themselves as clinically superior to more traditional toothbrushing methods.

It can provide benefits, but if you were to begin brushing your teeth with the M8S instead of a regular sonic toothbrush it is highly unlikely your dentist would be able to tell at your next checkup.

Potentially, someone with gum disease and higher bacterial counts might get better results in the long term if using an ultrasonic toothbrush with sonic vibrations compared to using a sonic toothbrush only. 

But, there is little evidence that confirms this. The long term studies have not been completed. 

Based on what we know the difference in results between each are unlikely to be clinically significant and impactful as you might hope. There are many other variables that affect our oral health.

Megasonex M8S review 3
M8S box contents

Use it like you do a manual brush

With many electric toothbrushes, it is the brush that does the work, not you. 

As a result, the way you move the brush is different when using an electric brush, compared to a manual toothbrush.

Megasonex recommends moving the brush in small circular motions, like you should with a manual brush.

You are, if using the sonic vibrations still getting the benefits this brings too.

Megasonex M8S review 4

Different brush heads that lock into place

The brush heads do slide on and off the M8S brush handle, but you have to lock them into place ideally.

A small section at the bottom of the head can be twisted about 45 degrees to the left to lock it into place.

You then twist it about 45 degrees to the right to unlock the head.

If you try to fit a head to the handle in the locked position, it is initially a bit more tricky and the mechanism will twist to the unlock position, ready for you to lock it back into place.

In the box with the M8S you get 3 different heads.

  • 1 x Soft brush head (sawtooth)
  • 1 x Medium brush head (sawtooth)
  • 1 x Tongue scraper

For brushing the teeth, it is the soft bristled head that is our preference. This is the white bristled head. The one with blue bristles is medium firmness.

Provided are what Megasonex call ‘sawtooth’ heads. This relates to the bristle formation and is what many might know better as the W profile to the bristle tips.

Essentially, when you look at the side profile of the head the bristles are of varying lengths with a wavy pattern.

They do too offer ‘flat’ heads, where all the bristles are the same length.

There might be some science to say one is better than the other, but the evidence isn't extensive as far as we are aware.

Soft bristled sawtooth brush head on Megasonex M8S
Soft bristled 'sawtooth' brush head

It is worth noting that the tips of each Dupoint tynex fibre bristle have been polished so they are softer and not sharp to the teeth and gums. This is a differentiator between premium and cheaper brands.

You don’t need to use a specialist attachment to clean the tongue, but the provided scraper is likely more effective than using a brush head alone.

It attaches just like other heads, except rather than bristles you have a large rounded scraper to drag across the tongue.

Although provided in the box as a sample, you don’t need to use Megasonex’s own toothpaste that uses hydroxyapatite rather than fluoride.

Clean and inoffensive design

It would be nice to see the M8S available in colours other than the basic gloss white that is standard. But, I can’t really criticise what they have produced.

The plastic body is practical, easy to keep clean and has a minimal look to it. It doesn’t scream cheap or overly premium.

The handle is mostly cylindrical with no notable buttons or controls on the back or sides of the unit.

At the front, the cylinder squares off with flatter edges to give it a bit of a different design and to help with grip.

Megasonex M8S review 5

In the upper third of the handle is 1 grey silicone button.

Beneath this are 2 LED’s, with silver icons beneath each. One is to show the ultrasound is functional and the other relates to the battery charge level.

About a third of the way down the handle, there is a slim silver ring that runs 360 degrees. It gives a nice break in the white plastic and looks smart.

Beneath this, the Megasonex logo is debossed onto the handle and finished in silver to contrast with the white body.

The handle stands upright on a countertop thanks to the flat base.

Remove the brush head and there is a long plastic shaft that fits inside the removable brush heads. It is this part of the brush that contains the Megacrystal.

The handle feels fairly durable and given it is IP68 rated it will survive daily brushing with ease. You can use this brush in the shower as a result.

I like the weight (80g) and balance of the handle it feels good in the hand.

Megasonex M8S review 6

The brush does potentially lack some textured gripping surfaces for some, but it doesn’t feel particularly slippery to the touch. One advantage is that it is easier to keep clean.

It doesn’t lay perfectly flat, it tends to tilt to the right or left a bit, but it also doesn't really roll on a countertop which is a good thing.

The button is quite clicky and gives some feedback. It is quite firm, but not stiff to the touch.

The standard brushing time is 3 minutes, not the more common 2 minutes

All of the brushing cycles on the M8 are configured to 3 minutes, rather than the more conventional 2.

The exact reason for this, I am not sure, but probably to encourage more thorough brushing and give more opportunity for the ultrasound to have maximum effect.

Like other good electric brushes, there is a pacer built in.

It has been configured to work on sextants, or 6 sections of the mouth.

  • 1 – Upper right back teeth
  • 2 – Upper front teeth
  • 3 – Upper left back teeth
  • 4 – Lower left back teeth
  • 5 – Lower front teeth
  • 6 – Lower right back teeth

The pacer is set to 30 second intervals.

At the end of the 3 minutes the brush will automatically power off.

There is no way to change the length of the cycle or the pacing. You can brush for 2 minutes if you prefer, you will just need to mentally keep track of the pacer or ignore it if you rather.

3 cleaning and brushing modes

You have the choice of 3 different cleaning modes on the M8S.

  • Ultrasound and sonic vibrations
    • 1.6MHz ultrasound
    • 18,000 sonic movements per minute
  • Ultrasound and gentle sonic vibration
    • 1.6MHz ultrasound
    • 9,000 sonic movements per minute
  • Ultrasound only
    • 1.6MHz ultrasound
    • No sonic vibration (except as part of the interval/pacer timing)

The modes are ordered as above. 

To access the ultrasound only mode, you would need to press the power button 3 times. You have to press the button within half a second to skip to the next mode otherwise the brush would turn off.

What this means is you can’t brush for 1 minute on 1 mode and then change to another without first turning the brush off.

Megsonex ultrasound toothbrush in the hand

The brush will not remember the last mode used, so if you used ultrasound only, the next time you turn it on, you will need to cycle through the modes.

Although you can tell the difference between the modes when the brush is operational, there are no different LEDs or cleaning mode labels on the brush handle.

The only confirmation you have is the blue LED beneath the power button. This confirms that the ultrasound is functional.

The sonic movements offered by the M8S are less than most regular sonic toothbrushes. It is noticeable in the sound of the brush and the brushing sensation.

I can’t say you are getting bad brushing results. In fact, used correctly, it doesn’t do too bad at all. But, you just don’t get the dentist clean feeling as you do with some brushes I have used, or you may well be used to.

If you prefer a softer and more gentle brush, then this certainly fits that category.

There are no alerts if you are brushing too hard

One of the features our dental professionals recommend is a pressure sensor.

Brushing the teeth too hard can be damaging to your teeth, and also the soft gum tissue.

Over long periods of time, hard brushing can wear away enamel and gums, leading to tooth sensitivity and gum recession.

A pressure sensor will detect when too much force is applied and help you take corrective action before it becomes a problem.

The M8S does not have a pressure sensor, thus you don’t get the alert. It is a shame it doesn’t have one.

Brushing harder doesn’t result in a better clean. The bristles of the brush need to virtually skim the tooth surface.

It doesn’t excuse the fact we would like to see a pressure sensor, but in their documentation, Megasonex does acknowledge that some brush too hard, advising those that do, to hold the brush with just 2 fingers. This approach limits the potential for brushing with too much force.

The travel case is great

I don’t want to get too checked up about a moulded piece of plastic, but the travel case supplied is really nice.

Made from a translucent plastic, you place the brush into the case either horizontally or vertically, depending on which way you are holding it.

It is designed so that the head remains attached to the handle and minimises the effort required to pop it in and out of the case.

It is only marginally taller and wider than the toothbrush itself.

Megasonex travel case

There are a number of air holes/vents top and bottom to ensure residual moisture can dry off.

The finish to the plastic isn’t smooth there is a nice texture that helps the case feel grippy in hand.

The Megasonex logo spans most of the lid of the case.

2 clips on the side of the case securely fasten to keep the brush inside.

It isn’t the best quality case I have ever used and you don’t have the ability to charge the brush whilst inside like you might with some premium brushes, but that doesn’t really matter.

A longer warranty than the majority

With the M8S, you get a 3 year warranty.

When the majority of manufacturers provide a 2 year warranty as standard, the extra year gives that added peace of mind.

Oral-B does offer a free 3rd year of warranty to UK customers on most brushes, but you have to register before the end of 2 years to benefit from such.

Of course, brushes can and do go wrong, but the vast majority don’t fail until outside of the warranty period, so for the small number of extra products Megasonex might have to deal with during this time, I believe the benefits far outstrip the costs to the company.

Summary of design, usability, clean & general use

Ultrasonic toothbrush - works differently to a regular sonic toothbrush
Sonic vibrations included for added cleaning effect
Backed by science
Same brushing technique as a manual brush
A range of brush heads included
Timer and pacer built-in - 3 minute cleaning cycles
3 cleaning modes
Quiet in operation - silent on ultrasonic only mode
Neatly designed handle
IP68 rated
No pressure sensor
Travel case included
3 year warranty

40 uses per charge of the battery

Sealed inside the handle of the M8S is a rechargeable 250mAh Nickel Metal Hydride (NiMH) battery that is said to give 40 uses on a full charge.

In my hands-on testing, using the standard mode with ultrasound and full sonic vibrations, I achieved 80 uses on a full charge. That is double the suggested life.

It is equivalent to over 5 weeks of use on a single charge.

Bearing in mind that the brushing mode is 3 minutes in length compared to 2 minutes like comparable sonic toothbrushes, this is impressive.

Arguably the sonic motion is less than some competing models, so that has a part to play too. But all things considered, I am very pleased with the results.

Even if you achieve only the suggested 40, that is still very good.

NiMH rather than Li-Ion

There are arguments for and against these different battery technologies.

Both are tried and tested and each have their supporters and their opponents.

The vast majority of electric brushes do now use Lithium-Ion (Li-Ion) in preference to NiMH. Li-Ion is the same technology used in smartphone batteries.

Based on this, it is somewhat surprising that the M8S uses NiMH, but it does.

USB charging stand and cable supplied

To charge the M8S you must sit it in its provided charging stand.

Megasonex M8S charging stand

White in colour like the handle, the plastic charger is a bit bulkier than most other toothbrush chargers. It measures about 7.5cm long and 6.5cm wide.

It is lightweight and has feet on the bottom to help it not slip on a countertop.

The brush stands upright from its central mounting position.

It charges wirelessly in the stand, you don’t connect a power cable to the toothbrush itself.

The right side of the stand has a USB type-c female connector for power.

Into this, you can connect the provided USB type-A male to USB type-C male cable.

The white cable is a flat cable and measures about 75cm/30 inches/2.5 feet long.

Is the 2 pin power adapter necessary?

The beauty of having a modern USB type c connector is that it is an internationally recognised cable/connector and replacements are easily accessible.

In fact, you don’t need to use the supplied cable if you don’t want to.

As USB c becomes more common, the company could have potentially left the cable out altogether as many people now own such a cable. Perhaps a step too far?!

USB type c charger of Megasonex stand

Included in the box too is a USB to 2 pin power adapter.  This allows you to connect the provided USB cable to it and power it from a wall outlet.

The adapter provided is a 2 pin European plug rather than 2 pin US or 2 pin UK shaver socket connector.

For the sake of environmental reasons, this could have been left out as most do also have USB plug adapters like this.

Although sold with a Euro plug adapter, you can buy and use this brush in other regions of the world, you just need a different adapter or power source.

You can connect the provided USB cable to a plug adapter you may already have or alternatively, you can charge it from a USB battery bank, wall socket or computer if you so wish.

Battery charge indicator on the handle

The lower of the 2 LEDs on the brush handle gives feedback on the battery charge level, which is great.

The LED colour and status when on charge is as follows:

  • Pulsing/flashing red - The battery is fast charging
  • Solid white - The battery is about 70% charged or greater
  • No light - The battery is fully charged

When not on the charger and in use, the LED will be white normally or red when it is low on power.

Battery LED on Megasonex M8

Important notes about the battery

Once the battery is charged to about 70%, the point at which the red charging light turns to red, fast charging is stopped and trickle chagrin begins.  It can take up to 18 hours to reach 100% charge.

Once fully charged, the light will turn off and the brush will stop accepting charge for the next 30 hours.

After this time, if in the charging stand, it will wake up and begin accepting a charge.

It can’t be overcharged as charging will stop when it is full.

Megasonex state that taking the brush out of the charging base will reactive the charging mechanism and the 18 hour timer. 

Used or not the battery should be charged fully every 2 months.

The battery can degrade over time and it is recommended that every few months the battery is discharged fully and then allowed to recharge fully over 18 hours.

Summary of battery life

NiMH battery sealed inside brush handle
Claimed 40 uses on a single full charge
Achieved 80 uses on a full charge
Cleaning cycles last 3 minutes rather than 2 minutes of most brushes
Charging stand provided
USB type C connector on charging stand
USB A to USB C cable provided
LED to show battery charge status
Takes up to 18 hours to recharge fully

Price & where to buy

I have included links to buying options here at the start of the review.

In the section below, I discuss the price more generally and in relation to similar products.

Being different often commands a premium. 

Megasonex is one of the two major brands selling ultrasonic toothbrushes. And as such, the M8S certainly commands this premium.

The M8S is expensive

The retail price of the M8S is $240 (approx £190).

Everything on the Megasonex website is priced in US dollars, even if your shipping location is in Europe or other countries that use different currencies.

When buying direct, PayPal is the payment provider and as such, the US dollar amount is then converted to your local currency.

The exact cost is going to depend on the exchange rates at the time of ordering.

At the time of review, the cost in Great British Pounds (GBP) is around £190, but it could easily be £20-25 cheaper or potentially even more expensive subject to the exchange rate.

When buying direct, you do have to spend a minimum of $50, but shipping is included. All items are shipped from Hong Kong and you may well be liable for import duties etc, depending on your country.

We actually purchased ours via a German based seller on eBay. It was sold in Euros and worked out at around £150 including shipping.

Due to the rather limited number of buying options globally, you are going to have to expect to pay the full retail price or close to it.

Shop around and see if you can find other stockists, but do be aware, your options will likely be limited.

We did find the most competitive prices on eBay.

Megasonex M8S retail box

How does the cost compare to Emmi-dent ultrasonic?

Emmi-dent is the main competitor for ultrasonic brushes. Its website offers regional based pricing.  This potentially allows for more competitive pricing and less reliance on that days currency exchange rates.

Whilst the models and features might well be a bit different, as a general rule the prices are comparable. Emmi-dent is approximately £30-40 cheaper than Megasonex, so not a great deal of difference.

This premium might well be justified when you compare how each looks, feels and performs in daily use. In my opinion, the Megasonex looks better.

How do ultrasonic brushes compare in price to regular electric toothbrushes?

There are a number of variables, but sonic or oscillating and rotating toothbrushes in the same price region as Megasonex tend to offer more features and functions not available on the M8S.

This could be lots of additional cleaning modes, extra accessories, brush heads and now often Bluetooth and smart connectivity features.

So, it isn’t quite like for like.

If you based it on cleaning modes alone, the Megasonex compares to something in the region of £50-£80.

Regular electric brushes tend to have inflated retail prices and actually sell for 20-50% less than this. Thus a £200 toothbrush might actually sell for £100 most of the time.

From what we have seen this discount isn’t anywhere near the same with ultrasonic brushes.

Thus, you can potentially buy one of the most feature rich brushes, for the same price as this ultrasound one.

But, our most recommended models tend to be in the region of £50 or less. Thus you can actually get up to 4 of these for the same cost as 1 of the M8S handles.

Potentially with a bit of shopping around, like we did the difference reduces, but you get the idea.  You are paying a fair premium for the limited availability and technology.

Megasonex M8S review 7

You need to think about brush heads

You want to be replacing brush heads around about every 3 months, as you would be advised with any other toothbrush.

A pack of 2 costs around $10/£8, or $5/£4 per head. 

This is better than I anticipated and is pretty much on par with the leading competitors.

The catch, if you like, is that because Megasonex isn’t widely stocked, sourcing them is a bit harder. You probably need to go online and buy them, rather than being able to pick them up from your local pharmacy for example.

When buying direct, you are going to need to order more, as there is a minimum order value.

When looking to buy from other stockists, the prices seemed to be a bit higher at about £6 per head.

The long term ownership costs

As a rough guide, priced over 3 years, the M8S will cost £240. This assumes 1 user.

Shop around and buy from another seller, like we did and that cost potentially reduces a bit to around £210.

Our top recommended brush, the Pro 3 3500 costs about £78 over 3 years. So, for the cost of 1 Megasonex, you can buy that 3 times over.

Please note that all prices quoted are approximates and will vary based on location, supplier and time of purchase.  These figures were correct at the time of writing and should not be relied upon as hard fact, but used as a guide during your decision process.

Summary of price & where to buy

Retail price of $240 - approx £190
Limited stockists
Up to 4x more expensive than a regular electric toothbrush
Replacement heads cost $5 (£4) each
Costs approximately £240 to own over 3 years

My thoughts on reliability and repairability

We’ve tested many different electric toothbrushes over the years, but this is my first ultrasonic toothbrush.

Not that should really change things when it comes to reliability, but it does essentially have tech in it compared to the more conventional electric options.

Over the weeks I have been testing this brush I haven’t had any reason to be concerned about the ongoing durability of this brush.

Megasonex talks a good game on its website about how they focus on quality and really put this about making a bigger profit. And whilst only time will really tell how well this lasts, my hands-on experience would suggest the company does pay a bit more attention to detail than most.

It is hard to describe, but when you feel it and hold it, the way the brush is balanced and small things do make you think that an extra bit of thought went into things here.

An IP68 rating ensures it has some tough water resistance. It is rare for any manufacturer to state the resistance their brush offers.

I certainly have no immediate concerns, in fact, I am more buoyant about the reliability when the company has set the warranty at 3 years, rather than the more standard 2 or 1 years of competing brands.

And it’s not like you have to register or anything to get this 3 year warranty, it's offered as standard.

When brands go above and beyond, to me this says something. It gives more peace of mind, even if it does go wrong.

Unfortunately, no parts on the brush are designed to be user serviceable. This isn’t uncommon for an electric toothbrush. With a need to move to more sustainable approaches, this is disappointing.

The manual would also suggest that the battery is a consumable and is excluded from the warranty. This is definitely a negative. I am not a lawyer, but given this is sealed inside the handle, I would question where you stand if after 2 years of use you get only 10 brushing sessions from it, rather than the claimed 40 for example.

Such exclusions somewhat tarnishes what seemed like a good warranty. Particularly as batteries tend to be one of the more common failure points.

Not having had to use the service/warranty, I am not in a position to comment on how well it is supported in reality.

Environmental impact

Electric toothbrushes don’t fare well in their impact on the environment because of materials needed for their electrical components, heavy weight when shipping, and the need to be disposed of as e-waste.

This doesn’t mean that you shouldn’t use one. You need to balance effective cleaning and disease prevention against the environmental impact.

Electric toothbrushes can reduce the need for dental treatment. And avoid the need for planetary impacts that come from procedures such as fillings.

There is a lack of detailed evidence to confirm that a filling is worse than use of an electric toothbrush. But, with the data available, dentist Gemma Wheeler believes that a single filling is worse than an electric brush with a usable life of 5 years.

There is no perfect solution as yet. We want to see manufacturers doing more to tackle this issue and achieve significant improvements.

Schemes to recycle brush heads only scratch the surface of what needs to be done.

Related to the M8S specifically:


  • 3 year warranty
    • Longer support times to encourage and help the brush remain usable for longer.
  • Quality components & manufacturing
    • Megasonex talk about their focus on investing and using better materials, components and factories with higher standards of welfare and environmental consideration.
  • USB charging stand supplied
    • With USB type-c connectivity it is easily recharged as it is a more standard and internationally recognised connector.


  • Box contents
    • Not all extras are necessary. They are adding to the size and weight.
    • Foam material inside that can’t be recycled easily.
    • The 2 pin power adapter could be removed as could the additional brush head styles and sample toothpaste.
  • No user serviceable parts.


Whilst I don’t recommend this as a must buy for the vast majority of people, I can’t say that this is a bad brush.

It has an inoffensive design, it is relatively lightweight, the battery is reasonable, the box contents is good and the travel case is a well thought out accessory.

Yes, it does lack the pressure sensor, but if we focus on the fact that this is an ultrasonic toothbrush, it is arguably not needed.

The issue here, if I dare call it that is around the price and availability of the brush for the claimed benefits.

At around 2-3 times the cost of a standard sonic toothbrush, it is hard to justify the premium, given the relatively limited evidence that proves the benefits over existing sonic and oscillating toothbrushes.

You can’t normally go and get this from your local dental office or pharmacy, you have to buy from select outlets, normally online and await delivery.

If this was a regular sonic toothbrush priced at £50 for example, I would be speaking very highly of it.

If you are set on an ultrasound brush and appreciate the pros and cons, then go for it, I don’t think you will be disappointed.

For the rest of us, a regular, more affordable electric toothbrush is more than good enough.

Size guide

  • Toothbrush height with head - 22.5cm / 8.9 inches
  • Toothbrush height without head - 22cm / 8.7 inches
  • Width - 2.4cm / 0.9 inches
  • Depth/thickness - 2.3cm / 0.9 inches
  • Weight with head - 80g / 2.8oz
  • Weight without head - 77g / 2.7oz
  • Travel case size - 23.4cm / 9.2 inches (L) x 3.6cm / 1.4 inches (W) x 3cm / 1.2 inches (D)
  • Travel case weight - 44g / 1.6oz without brush or 124g / 4.4oz with brush
  • Package weight - 733g / 25.9oz


  • 0-51dB

Country of manufacture

  • China


M8 vs M8S

  • The M8S comes with a 3 year warranty compared to the 2 years of the M8.
  • The battery offers up to 40 uses per charge with the M8S, compared to the 28 of the M8.
  • The M8S uses USB type-c charging rather than a proprietary 2 pin connector of the M8.
  • The M8S is IP68 rated vs the IP54 of the M8.
  • The M8S comes with more in the box.
    • Both models include the handle, travel case, 2 brush heads & charging stand. 
    • The M8S includes:
      • Tongue scraper.
      • 5ml toothpaste sample.
      • A separate USB-A to USB-C cable and a USB charger.
  • The M8 costs around $190 compared to the $240 of the M8S.
  • The M8S is available with a 2 pin European plug adapter only. The older M8 is available with a 2 pin US, Euro and Australian power adapter.
  • Although the M8S only comes with a 2 pin European power adapter, it can be used in the USA and other countries because it actually charges via a USB A to type C cable. Connect it to a computer, power bank or use the appropriate USB power adapter, such as those that come supplied with a smartphone and it should be ok to use.

Does the M8S have a pressure sensor?

No, it does not.

Does the M8S have Bluetooth?


Can I use the M8S in the shower?

Yes. The M8S is water resistant, IP68 rated so if you choose you can use it in the shower. Avoid submerging it in water.

Author: Jon Love

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