Oral-B iO Series 9 Electric Toothbrush with 4 Brush Heads, Aqua Alabaster

Why it's worth it

The iO Series 9 pairs Oral-B's round oscillating-rotating head with magnetic-drive micro-vibrations and a color screen on the handle. You get seven modes, a pressure sensor that shows green, red, or white, and app-based tracking of which spots you keep skipping.

The round head is the reason to start here. Oral-B's small circular brush wraps a single tooth at a time and slips under the gumline in a way a rectangular head struggles to match. That matters most in the back molars and along the sulcus, which is exactly where gingivitis starts. A meta-analysis in the Journal of Clinical Dentistry found oscillating-rotating brushes beat sonic brushes on plaque removal in 11 of 16 comparisons across more than 5,000 patients. It's not a blowout, but it's a consistent edge.

The pressure sensor is the feature we'd protect if you had to strip everything else away. Toothbrush abrasion affects an estimated 10–20% of adults, and it's one of the most preventable causes of gum recession. Research in the Journal of Periodontology found pressure-sensor feedback cut applied force by over 60% within four weeks. On the iO 9, the light ring glows red the moment you lean in — no menu diving, no app required.

From our review of 8 dentist-recommended electric toothbrushes, by Eleanor Vance, Health & Beauty Editor

What we like

• +The round head is the reason to start here
• +The pressure sensor is the feature we'd protect if you had to strip everything else away
• +The screen on the handle does more than look expensive
• +The seven modes are more than you need, and that's fine

What to know

• –It's the most expensive brush in this guide, and the gap between it and the iO Series 4 is much wider than the gap in how clean…
• –The charging base draws real complaints
• –The app is optional but pushy