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FACT: Your teeth are held in your mouth by ligaments, and you’ve probably sprained them before
Your teeth don’t just sit pretty in your jawbone without any assistance: They have ligaments to hold them in place. And while it’s not exactly the same as the ligaments that attach your other bones and cartilaginous structures to one another, those tooth-supporting tissues can still get sprained.

Collectively called the periodontal ligament, or PDL, the specialized fibers that hold your pearly whites in place act as shock absorbers whenever you bite, grind, chew, or otherwise put pressure on them.

As this Vice article explains, the PDL doesn’t sprain the way a ligament in, say, your ankle can—by tearing or stretching in a way that impedes its ability to connect one bone to another. But you can still strain and damage your PDL to the point of pain, and many dentists refer to this as a tooth sprain. The sensation of stretching or tearing the PDL is often mistaken for a cracked tooth, and can be quite painful. Luckily, the pain comes from inflammation—there’s nowhere for the swelling ligament to go, so it presses up against your jawbone and your tooth—so anti-inflammatory medication can help and symptoms usually abate within a few days.