Last night I kept losing my own teeth

I'm in a white room with too many chairs, and every time I open my mouth to speak I feel a tooth go loose and fall out onto the floor. I try to gather them up, but they keep multiplying—there are hundreds by the end. Woke up with my jaw clenched and couldn't figure out if I was mad or just tired. It's the kind of dream that stays with you all morning, like a grain of sand in your shoe.