Philips Sonicare

DiamondClean Smart 9400 (HX9917/89, HX9918/89, etc.)

Philips Sonicare DiamondClean Smart 9400 (HX9917/89, HX9918/89, etc.)

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Overall

#53 in

Electric Toothbrushes

according to Reddit Icon Reddit

Sentiment score58% positive
7
2
3
Last updated: Apr 29, 2026

Reddit Reviews

Reddit IconBackground-Camel-713
6 months ago

Not sure which route you’ve went, I’ve had 3 9400’s , one 7400 and currently I have the cheap one, I hate it , it’s not near as powerful, they don’t last long in general, but a good toothbrush feels so much better, I recommend spending the money and don’t expect it to last long, I’m lucky to get a year out of one

Reddit IconBose321
3 months ago

I really wonder how you can break them that much. Me and the wife are using a 9400 for years without any issues.

Reddit Icondot-M
9 months ago

My two Philips Sonicare DiamondClean Smart 9400 for German market are made in China. Also we have a chinese made Sonicare 5100

Reddit IconComeHereOften1972
7 months ago

Black Sonicare herrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrre. It’s goooooooooooooooooooooooooooooood

Reddit IconNancy6651
3 months ago

I've been using Sonicare toothbrushes forever. I usually get the package of 2 of them, in case I can convince my husband to use one (unsuccessful so far) or for travel. I like the one I have now since it has more "intelligence" and lets me know when to replace the brush head.

Reddit Iconlumixjourney
2 months ago

I had one of the old diamondclean models and it stopped working so i ordered a new diamondclean model from philips which was useless - i ended up buying the older model from aliexpress and it worked perfectly

Reddit Iconponytrack
11 months ago

Bought the highest end sonicare set three times. One of the two always developed really loud buzzing sounds. Theoretically it could be fixed, but I opted to return and replace. After using sonicare for 15 years, what back to oral b. Design isn’t as slick, but works great and was way cheaper. We’ll see what my dentist says in six months.

Reddit Iconnanomax55
12 months ago

Sonicare diamond clean user here. Going strong 4th year. Before the black redesign i had the white one. It worked great no issues but the power button seal broke and I started getting water in so I replaced it.

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