yes … to a certain extend (regulated by the law, I don't want to go in details here)

Yes, except all esthetical stuff (colour lents, sun glasses with “corrective” glass, white teeth…).
Example. You need glasses. Cost: Doctor consultation: 60 euro. Glasses : 350 euro
The social security paid a part of 60 euro (example half), a part of glasses and a (smaller) part of the frames. i.e 200 euro (50 for glasses and 150 for frames). It is enough for good glasses but not for “branded” one. If you have a complementary policy (insurance) that almost every company propose and pays part or all cost, you will be reimburse of the remaining cost.
How does this is all financed?? Every worker pays a “small” amount for the social secutity and of course not every one needs glasses so that if 1 out of 500 workers need it, the cost will be 230/500 = 0.46 cents for every one. Don’t know if this is a good system or not, but that’s the ways it works.

Hope this help …
Take care,