How to use?

Maybe,

I've to see a dentist becuase I need a tooth operation.

or possibly... just a thought...

"because"

maybe not

You could say I have to have an operation on my tooth but this sounds odd, although dentists do things to your teeth you don't really call it an operation.

I have to have dental surgery is fine though.

I need/have to to undergo dental surgery
perhaps a bit too formal

"I have to do the tooth operation" or does it mean i'll do by myself.

Are you focusing on the difference between do and have (done)?

I have to do dental surgery. You are going to do it yourself (on someone else).
I have to have dental surgery. Someone else is going to do it (on you).

I did

Hi,

I think the following are what most of people in English-speaking countries would say:

I have to go to the dentist and get my teeth fixed.

I have to go to the dentist and get my dental work done.

Like Nona said, the word "operation" doesn't seem to belong in that context. I value dentists very very highly but sadly, the terms that describe some of the thing

i think that it can also be something like:

I will have my tooth done.

(I will have to have my tooth done)

Kane, "I will have my tooth done" is not standard usage, at least not in the U.S. You can have your hair done (get your hair styled), or get your nails done (have a manicure), but not "have your tooth done."

Depending on the severity of what's being done, the suggestions above (I have to go have dental work done or I have to have dental surgery) are appropriate. You could

Grammar Geek You can have your hair done (get your hair styled), or get your nails done (have a manicure), but not "have your tooth done."

Some people have hairy teeth, though...

davkett:
great stuff