I lost two molars some years ago due to gum disease. No more. Made an adjustment to my own dental hygiene and not even so much as a cavity in the past 13 or so years.
I did have to have some tissue harvested from the roof of my mouth and grafted onto a couple sections of gumline in surgery I had in 2002. Lord God, there is no pain like that.
I do need to put in a mouthpiece at night because I'm a tooth-grinder. Does that count as a second set of teeth? 
I can't even imagine having skin grafted inside my mouth like that...lord, that must have been painful. It was painful enough for me enduring the excruciating pain I had from the gum disease. I brushed, flossed and rinsed and still got the gum disease.
What I can't get used to is the adhesive goo...jeez I can't stand that stuff, but the teeth look great. Perfect fit and unless I told someone, they'd never know.
I've been leaving them in at night and only taking them out to clean in the morning and back in they go. I can't stand for anyone to see me without them. I don't know, maybe as I get older I won't care as much like longview said...
Still have my lowers in, but I'm having them yanked out in the near future too. Anyone who's had a lot of pain with their teeth and gums understands. I was really depressed when I couldn't smile, now I have my smile back and it's made a world of difference.
The dentists are always saying that you want to keep your real teeth as long as you can, but...that's not so if you have constant pain from teeth and gum problems like I had. I would tell anyone in that situation...have them pulled and get dentures. I'm really happy with mine and I'm glad because I'm 57 and have quite a long way to go wearing dentures.