What Does the Pressure Sensor on an Oral-B iO Do?
Short answer
It tells you when you are brushing too hard. Oral-B says the iO's smart pressure sensor turns red when you press too hard and green when your pressure is just right, and on the iO6 it also signals when you are pressing too softly. Brushing too hard can contribute to receding gums and wear at the gumline, so the light helps you ease off in the moment.
What do the lights mean?
- Red: too much pressure. Lighten your grip and let the brush head do the work.
- Green: the right pressure, according to Oral-B.
Oral-B describes the iO6's 360 degree visible pressure sensor as signalling whether you are brushing too hard, too soft or just right.
Why does brushing too hard matter?
A 2025 review in the journal Healthcare looked at toothbrushing, gum recession and tooth wear. It cites research linking brushing forces above about 3 newtons to wear at the neck of the tooth and gum recession. In one study it cites, severe recession was seen at around 3.8 newtons and none at around 2.1 newtons.
The American Dental Association explains that when gums recede or enamel wears, the dentin underneath is exposed, and exposed dentin is a common cause of sensitive teeth.
Do pressure sensors actually change how people brush?
Yes. The same 2025 review notes that pressure-detecting brushes help people self-correct the force they use, and that in one study brushing forces fell within six weeks.
How hard should you press with an electric toothbrush?
Lightly. With an electric brush you guide the head slowly from tooth to tooth and let it do the scrubbing. If the light turns red, you are pressing harder than you need to.
Sources and evidence
- Kumar and colleagues, "The Impact of Toothbrushing on Oral Health, Gingival Recession, and Tooth Wear: A Narrative Review", Healthcare (2025): brushing force, recession, pressure sensors.
- American Dental Association, MouthHealthy, "Sensitive Teeth": exposed dentin and sensitivity.
- Oral-B, iO range and iO Series 6 product information: pressure sensor colours and signals.
Related questions
Is an electric toothbrush better than a manual one?
Yes. See what a review of 56 trials found.
Can brushing too hard cause sensitive teeth?
It can contribute. Worn enamel and receding gums expose dentin, a common cause of sensitivity.
How often should you replace Oral-B iO brush heads?
Every 3 months, or sooner if the bristles splay. Pressing too hard wears them out faster.
Relevant products
General information only, not dental advice.