My biggest advice is change positions a lot! Also, be *really* picky about how the latch is. You shouldn't really be getting much irritation from the bottom teeth because the tongue should be over them if the latch is correct.
Once I figured those 2 things out things went much better for us. That said, I do have scars on both nipples from where DD rubbed some raw spots while we were getting used to the teeth. My DD got 4 teeth within 3 week of her 6 mo birthday though, so it was just crazy!
If you do get a sore spot try this:
After nursing hand express a little milk onto your nipple, gently rub in & let air dry most of the way. I also applied Lansinoh when they were really bad.
There were a few days where I only nursed on one side because the other side was sore & just pumped that side. So that is an option as well.
My DD self-weaned at 11 mo anyway, but I'm SOOOO glad we didn't stop when she teethed at 6 months. If you'd like to continue I say be a trooper & it will get better over the next couple weeks. Most babies figure out pretty quick not to bite you because you stop feeding them when they do.
Best of luck whatever you decide!
PS: You may also get more ideas if you cross-post this in the Breastfeeding forum.