I have amalgam fillings that are probably twenty-plus years older than the dentist.
I have a several of those, on account of:
My childhood dentist [...] performed unnecessary procedures
In this case, there was a brief early-90s fad for capping children's perfectly good molars with some sort of UV-curing resin, presumably on the basis that middle class parents would pay handsomely in order to give their offspring a purported degree of immunity to sugar.
In practice, this mostly served to prevent the teeth from meshing together properly, until the resin (and underlying enamel) cracked under the stress, with the inevitable result of lots of mid-90s amalgam fillings. Credit where it's due, my particular dentist was a lot better with amalgam than she was with resin, to the point where they've never given me any trouble.
My latest toothiologist (who has probably removed me from the list since I turned down a checkup at the start of the pandemic), was keen to drill them out and replace them, on the basis that they were evidently very old. I muttered something about bathtub curves and ran away.
While we're on the subject, apparently the niblings (8 and 5 respectively) have both had a milk tooth pulled, which seems odd. I had to have a couple removed when I was a small, on account of them interfering with the growth of the adult teeth below. But that was done after x-rays and careful consideration, and with the aid of a whole brain-needle
[1] of anaesthetic. It appears that the niblings just got a swift yank, followed by lots of bleeding. Seems odd that they'd both need the same procedure like that...
[1] The ones normally brought out to persuade drunks that they don't want to be in A&E any more.