That's one of my worst fears. I dream about it all the time
They say that dreams about your teeth falling out are due to anxiety/stress. I think that's right because I have those dreams when I'm stressed about something.
Speaking of teeth, I had like 8 cavities when I was younger and I was SHOOK every time I had to get one filled in. It made the dentist a horror for me, and when I was 11/12ish they told me I had to get 4 teeth pulled for braces and I had a nervous breakdown I have impeccable oral hygiene now, so silver lining?