What do we mean when we say it today?
Shakespeare added a "nothing" in the middle of this saying to make sure we really got the point, but we've gone ahead and removed that little addition today. Sorry, Shakespeare! Nowadays, we usually hear someone say something "set my teeth on edge" when there's an unpleasant taste in the mouth, either literally or figuratively.
Sometimes the dentist or a sour candy can set your teeth on edge. Other times, it's just something that makes you uncomfortable or makes you annoyed. We'll tell you one thing: students not reading literature sets Shmoop's teeth on edge. See what we did there?