Well, it's the only time I have ever seen tears in my fathers eyes and it's the only time I've seen pain make him puke. Other than that, it's not so bad.
He waited too long and they had to break some of them to get them out.
I've had two out and it's pretty much like you imagine; a fairly strong man with pliers in your mouth, two handed, wrenching back and forth until they come free. Pressure, pressure, pressure...POP.
The worst for me was one of them, he left a shard and, because of the local, I didn't feel it. Turned inside of my cheek to hamburger and it got infected and swelled up like a golf ball was between my cheek and gum. Went back, he snapped the piece out with a typical doctor "Huh. Musta missed that piece..."