Amy, I'll be sure to let you know; from what the dermatologist told us about my son (He has it on his scalp, too) it shouldn't permanently prevent hair growth, though it might take a few years for the follicles to recover. I sure hope they're right...when I was growing up on the farm, one of our neighbors had a huge spot on his head where he had ringworm as a child back in the '30-40s, and his hair has never come back.

I seem to recall it as being about 2-3" across, so that's a pretty big spot...I hope modern medicine can avert that!
If you search on the internet, there are some pretty horrific, heartbreaking pictures of dogs with ringworm, some poor dogs pictured have spots that cover their whole side. While it's disappointing that we have to deal with it, I'm thankful I caught it quickly--the vet expects a full recovery in the next week or so for Daisy.
The bad part is the recent snow and cold makes her nose really red, so I have to monitor her snow-play so her poor nose doesn't get any more damaged. I'm sure some warmer, drier weather would go a long ways towards healing, too.
BarbR