teeth

It could easily be a regionalism, but this Californian would never, ever say "wash my teeth." On a daily basis I "brush" them, and once or twice a year I go to the dentist to have them "cleaned." (Or, I might also "clean" them with a toothpick.)

Not a regionalism - it's the same (even) for a Brit.

The only way I would "wash" my teeth would be if they were dentures and I was going to scrub them in the sink or something.

I would almost always "brush" my teeth. I might go to my dentist to have him "clean my teeth."

A bit of Googling showed me a lot of "tooth washing" on Irish web sites.

My father sometimes says wash, and when we were growing up we would laugh at him for it. My mother thought he was crazy for it. Brush sounds normal to me, along with cleaning the way zashibis says.

Both of my parents are of Irish descent and from Boston (USA), where the dialect was influenced by Irish people.

I agree with the Californians here -- I brush my teeth and have them cleaned at the dentist's.

I have heard several english-as-a-second-language speakers refer to 'wash'-ing their teeth. Certainly a reflection on how other languages describe the process.

When I was younger, I often went to the dentist to have teeth 'pulled'.

"I have heard several english-as-a-second-language speakers refer to 'wash'-ing their teeth. Certainly a reflection on how other languages describe the process."

That seems to be true.
We "wash" our teeth in Polish, and also all other parts of the body when it comes to personal hygiene. It doesn't matter if you use a toothbrush or a sponge. It's all "wash".
We brush our clothes, a suit or a coat, to remove hair or dust, we also brush or comb our hair, depending on what you use.

There's one distinction though. We don't use the word "wash" when we wash our cloths. There's another word "prać" which means 'to launder'.

hygienically (that's not a real word is it?)

I don't know if it's real but it's quoted on (some) English dictionaries.

Floss and brush your teeth.