I just had a 20+ year old crown fall off last month. Went to the dentist where he used his computer to scan the area after some cleanup work, sent it off to a 3D milling machine 50 feet away, did some light touchup work on it, cooked it at 900 degrees, and now I have a tooth that is a perfect fit that is 8 times harder then gold. All in 1.5 hours. Amazing.
While he was in there he noticed the other crown which fell off last winter (another 20+ year one) that the dentist just north of the boarder glued back on (she did it once before 5 years prior to the day) and shook his head. Think we might have to address that one also he said.
I left before I got the bill. I was having a good day and didn't want to spoil it. No 8 oz bottle of Walmart water to rinse my mouth out with either.