From your description, I'd guess he's a jersey wooly--it's really the only breed I know of in the US that is a long-haired (wool) lop. Could be a cross, of course, but jersey's the most likely.
As far as the issue goes, though, I would suggest making sure to check his teeth every day to make sure there isn't any hair on them at all (not just when it gets big). The long teeth may or may not be due to the hair wrapping around them, although it certainly doesn't help.
To help with the long teeth, make sure he always has fresh hay available, and good solid pellets (shouldn't be much dust in the bag). I also recommend some wood for chewing on, like apple or maple branches.
Do you brush him? Sometimes brushing to keep the mats out will help them when they have to groom. It also helps to avoid wool-block, which is essentially a huge hairball that stops the digestive tract and can be fatal if not treated.
Is he pulling fur from a certain spot? It's possible he has a wound under there that you haven't seen.
You can also shear the wool off, which might help you figure out if there's an underlying problem. It will grow back, and probably rather quickly if there's not a huge issue causing the hair loss.
