Reviews You Can Rely On

Oral-B iO Series 9 Review

For those searching for one of the most premium electric toothbrushes, you've met your match
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oral-b io series 9 electric toothbrush review
Credit: Natalie Kafader
Price:  $300 List
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Manufacturer:   Oral-B
By Ben Applebaum-Bauch and Ryan White  ⋅  Dec 16, 2023
85
OVERALL
SCORE


RANKED
#2 of 17
  • Cleaning - 40% 9.5
  • Comfort - 30% 8.5
  • Ease of Use - 20% 8.6
  • Battery Life - 10% 4.5

Our Verdict

The Oral-B iO Series 9 is no ordinary toothbrush; it's a tech-savvy companion designed for various brushing preferences. Boasting a user-friendly full-color screen, this is one of the best toothbrushes we've tested. It pairs seamlessly with the Oral-B app to offer insightful details about your brushing habits. Not only is it comfortable to hold and use, but its circular brush head and angled bristle pattern provide effective cleaning, especially in tight spaces between teeth. See how it compares to other top-ranked electric toothbrushes in our full review.
REASONS TO BUY
Flawless cleaning
Powerful yet comfortable
Travel case included
REASONS TO AVOID
Not budget-friendly
Leaky brush head

Compare to Similar Products

 
oral-b io series 9 electric toothbrush review
This Product
Oral-B iO Series 9
Awards Editors' Choice Award Editors' Choice Award Best Buy Award Best Buy Award Best Buy Award 
Price $300 List
$255.99 at Amazon
$100 List
$65.63 at Amazon
$50 List
$39.96 at Amazon
$40 List$60 List
$39.95 at Amazon
Overall Score Sort Icon
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Star Rating
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Bottom Line If money is no object, this model excels across the board; namely with cleaningNearly flawless, this model offers everything you need with minimal drawbacksInexpensive yet fully capable, this electric toothbrush is a solid choice for just about everyoneAn inexpensive minimalist toothbrush with a long-lasting battery that cleans wellAffordable, effective, and user-friendly — this device offers value with good cleaning and extra brush heads
Rating Categories Oral-B iO Series 9 Philips Sonicare Pr... Philips Sonicare 4100 Philips One Aquasonic Black Series
Cleaning (40%)
9.5
9.0
7.9
6.8
6.8
Comfort (30%)
8.5
7.9
7.7
7.0
6.1
Ease of Use (20%)
8.6
8.0
7.8
8.0
8.0
Battery Life (10%)
4.5
5.5
5.0
3.5
4.0
Specs Oral-B iO Series 9 Philips Sonicare Pr... Philips Sonicare 4100 Philips One Aquasonic Black Series
Measured Battery Life 38.5 days 46 days 49.5 days 30 days 31 days
Pressure Sensor Yes Yes Yes No No
Number of Brushing Modes 7 modes:
Daily Clean, Sensitive, Whiten, Gum Care, Intense, Super Sensitive, Tongue Clean
3 modes:
Clean
White
Gum Care
1 mode:
Clean
2 sensivity levels
1 mode:
Clean
4 modes:
Clean, Soft, Whiten, Massage
Estimated Annual Brush Head Cost $49.99 for (1) four pack $44.96 for (1) four pack $44.96 for (1) four pack $15.92 for (2) two packs $19.90 for (2) two packs
Charger or Battery Info 100 - 240VA
50-60Hz
3.0W
100 - 240V a.c.
50/60Hz
0.4 - 1.4W
USB
(block not included)
USB 100 - 240VA
50-60Hz
0.8 - 1.6W
American Dental Association accepted? Yes Not Listed Not Listed Not Listed Yes
Waterproof / Resistant Yes, can use in shower Yes, can use in shower Yes, can use in shower No, cannot be used in the shower Yes, can use in shower
Number of Brush Head Styles Available 4 styles, most available in 2 colors 8 styles, most available in 2 colors 8 styles, most available in 2 colors 1 style available in multiple colors 3
Number of Included Brush Heads 3 1 1 1 8
Thirty Second Reminder Yes Yes Yes Yes Yes
Two Minute Alert Yes Yes Yes Yes Yes
Travel Case Included Yes Yes No Yes Yes
Measured Handle Weight 4.9 oz 4.4 oz 3.2 oz 1.4 oz 3.6 oz
App Yes No No No No
Available Colors 4 2 3 4 1

Our Analysis and Test Results

The Oral-B iO Series 9 soared through all of our tests with relative ease, with very few drawbacks. However, the sticker shock is undeniable, making the price a considerable factor. If you can overlook that, you'll be treated to a top-of-the-line electric toothbrush that can dramatically enhance your overall dental hygiene. Plus, for those who appreciate analytical data, it adds a touch of fun to your oral care routine.

Performance Comparison


No dental models were harmed by this test.
Credit: Natalie Kafader

Cleaning


Our comprehensive testing involved a variety of methods, including having our skilled testers chew a plaque dispensing tablet to highlight plaque with a pink tone. This allowed us to properly gauge how effectively the electric toothbrush cleaned off plaque during the recommended two-minute cleaning session. Both before and after brushing photos were taken. However, prior to our testers visually assessing the results, they were prompted to report the cleanliness they felt after using each brush.


Before brushing with the Oral-B iO Series 9.
Before brushing with the Oral-B iO Series 9.
After brushing with the Oral-B iO Series 9.
After brushing with the Oral-B iO Series 9.

The Oral-B excelled in this metric, providing an overwhelmingly clean feeling and obliterating all visible plaque. To ensure thorough testing, an artificial dental model was used as well. Coffee grounds and pesto were spread across the teeth and gums, and our testers used the device for one minute to evaluate the efficiency of the brush. Again, the brush succeeded in clearing out all visible debris.

oral-b io series 9 electric toothbrush review - testing all intensity settings to ensure there is no discomfort.
Testing all intensity settings to ensure there is no discomfort.
Credit: Natalie Kafader

Comfort


To guarantee utmost comfort, we thoroughly tested each brush, scrutinizing every mode and ensuring none of the devices registered too loudly on our decibel reader.


This brush provides a comfortable user experience with seven diverse modes to suit various preferences. From super-sensitive to intense and gum care to tongue cleaning, each setting offers a unique intensity and rotation pattern to accommodate a wide range of users. While the handle may feel a bit heavy, it remains comfortable to grip. Our testers discovered that even the most intense setting was not overly powerful, but individuals with sensitive gums should exercise caution. The handle features an indicator ring around its neck that changes colors to convey intensity levels—green for optimal, red for excessive pressure, and white for insufficient pressure. This feature is essential for proper comfort and cleaning effectiveness.

The overall loudness is just one side to the story, as the frequency of the pitch plays a role as well.
Credit: Natalie Kafader

While most electric toothbrushes emit a motorized sound, it might not be a significant concern for some. However, we firmly believe that a device used multiple times a day should seamlessly fade into the background and not dominate the sound stage in your bathroom. Additionally, the pitch of each device is crucial because, though some may be quiet, they may produce a less-than-ideal hum. We found the Oral-B to give off a pleasant enough sound, and it wasn't too loud, registering a maximum of 73 decibels when our decibel reader was 3 inches away.

oral-b io series 9 electric toothbrush review - the simple interface includes a power button, a small screen, and a...
The simple interface includes a power button, a small screen, and a mode switching button.
Credit: Natalie Kafader

Finally, we encountered a flaw in an otherwise nearly perfect device: the holes in the brush head. Regrettably, this appears to be a persistent issue across various Oral-B models. Essentially, these holes allow a mixture of toothpaste and saliva to leak while brushing, which, from a comfort standpoint, is not particularly enjoyable. While the device is water-resistant, allowing you to use it in the shower to mitigate this issue, it's not an ideal solution either.

oral-b io series 9 electric toothbrush review - the soft brush head paired with the multiple modes proved effective...
The soft brush head paired with the multiple modes proved effective and comfortable for a wide variety of testers.
Credit: Natalie Kafader

Ease of Use


While ease of use may not be our most critical metric, it still contributes 20% to the final review score. We assess this aspect by testing each mode offered by the electric toothbrushes, evaluating the simplicity of swapping between modes and indicators of the active mode. Additionally, we examine the ease of cleaning for each brush and verify if the device includes a built-in two-minute timer.


The bottom button on the Oral-B iO Series 9 offers a convenient way to switch between brush modes or adjust the LED ring light color to suit your preference. This high-tech device offers seven modes: Daily Clean, Sensitive, Whiten, Gum Care, Intense, Super Sensitive, and Tongue Clean. It sounds like a lot (and it is!) but most folks will find themselves only needing a couple of these modes. An added convenience is the ability to switch between settings even when the brush head is powered off — a feature we appreciated. Moreover, the device remembers your last used mode, defaulting to it the next time you power it on. The crisp fonts are easy to read on the digital screen, and it even greets you with a 'good morning' and a smiley emoji. Each subsequent mode has a unique icon and label, too. These little touches add to the depth and fun of this device without sacrificing its user-friendliness.

oral-b io series 9 electric toothbrush review - the small screen displays various icons throughout the cleaning...
The small screen displays various icons throughout the cleaning process.
Credit: Natalie Kafader


Thankfully, the iO Series 9 includes a handy two-minute timer that is displayed on the digital screen and counts down in real-time. Once the two minutes have passed, the screen displays a smiley face with star eyes. If you turn the brush off before the two minutes, you'll notice a sad face. All in all, these are useful features that enhance the overall experience. While we appreciate the inclusion of a two-minute timer, we wish the brush would automatically shut off at the end of this period or offer a customizable setting for users who prefer it. Currently, the brush continues running beyond the two minutes. All of this brushing data can be viewed from its mobile app. Additional brush heads can be ordered here as well.

oral-b io series 9 electric toothbrush review - the io series 9 can be paired with a mobile app to give in-depth...
The iO Series 9 can be paired with a mobile app to give in-depth details about your brushing.
Credit: Natalie Kafader

As highlighted in our comfort section, the issue with holes in the brush head also impacts the ease of use metric. This flaw not only creates a bit of a mess during brushing but also adds to the maintenance routine. Residual toothpaste and saliva can seep into the brush handle, and while the device is water-resistant, regular cleaning is essential to prevent unpleasant build-up.

oral-b io series 9 electric toothbrush review - when the time comes, the brush head easily pops off and can be...
When the time comes, the brush head easily pops off and can be replaced.
Credit: Natalie Kafader

Battery Life


To get an accurate representation of the battery life, we ran each brush twice a day for a total of four minutes (two minutes each time) to simulate typical daily use. Additionally, we sought features that would allow us to easily determine if the battery was running low.


The Oral-B iO Series 9 goes the extra mile with its continuous battery charge indicator displayed prominently on the screen, offering a precise readout down to the exact percentage. As an added visual cue, the LED light encircling the neck illuminates in a vibrant red hue, signaling a low battery level. We were able to get 38.5 days of life out of the Oral-B, which is impressive. Once fully depleted, it only takes 3 hours to charge up to full capacity. The travel case that comes with this model doubles as a charger as well, so unless you're away from power for long periods of time, it should last more than long enough for travel. Yet another feather in the cap of an already solid device.

oral-b io series 9 electric toothbrush review - the oral-b is a straightforward toothbrush, yet boasts all the...
The Oral-B is a straightforward toothbrush, yet boasts all the bells-and-whistles like an LED screen.
Credit: Natalie Kafader

Should You Buy the Oral-B iO Series 9?


If you're considering this model as an investment in your dental health, rest assured you won't be disappointed. While we acknowledge the steep price, we believe it's justified if you have the means to invest in it. The extended battery life, travel case, and excellent cleaning performance take this toothbrush to the next level. We confidently give the Series 9 our full recommendation.

What Other Electric Toothbrush Should You Consider?


The Philips Sonicare ProtectiveClean 5100 is another excellent option at a friendlier price point. Like the Oral-B is does a great job cleaning, has an extended battery life, and includes a travel case. If you're looking for a minimalist toothbrush that will last for months on end, the Quip is worth considering. This basic model is budget-friendly and more closely resembles a manual toothbrush. If you want to see how these units stack up against analog brushes, check out our best toothbrush review.

Ben Applebaum-Bauch and Ryan White