Teeth grow continuously and if they don't have enough material to wear off the teeth they can grow in a spiral and make it difficult for the animal to eat. Skull ID site
The nasal cavity on yours doesn't look like the one pictured for beaver, though. It's definitely a rodent, though.
. I edited the subject and my first post....
Congrats, I think you are correct. And the only one to have guessed that, too. I had posted it on Facebook and the guesses there were beaver, woodchuck and rabbit.
I really need to get the actual size measurements, to satisfy my curiosity.