How much does a wisdom tooth extraction usually cost?

I'm due to have my remaining three wisdom teeth removed and will be charged about €620 for all three (190 each for two and the remainder for the third one as it has only partially come out)

I realised later that I was at a dentiste non-conventionné, so obviously they can charge what they like, but I just want to make sure I'm not being totally ripped off.

Also is there a chance I will be reimbursed? The lady at reception seemed to say no, unless my additional insurance from work covers it, but other sources online seem to say yes.

Any help appreciated, thanks.