I was in the chair at the dentist the other day waiting. I heard this constant strange noise I could not place so I got up out of the chair to investigate. It was a box like the 3d printer in this video making a tooth! I got back in my chair before I was caught out of my chair, no knowing what a dentist can do to you for wandering. I asked if that was a 3D printer. I got a laugh and was told he got that machine some 20 years ago.
For anyone else confused about this technology, what the dentist had was a computer driven lathe which have been around for 40 years, even some decades before that they existed as Numerical Code machines. Such machines work from the premise of removing material to create a defined object. 3D machines add material to create a defined object. At this time only forms of plastic.