I've taken a few bare-knuckled punches to the face in training and sparring, never remember taking one in a fight (except maybe schoolyard fights when I was younger; don't really remember most of those). The most memorable one was when I was younger and I got a tooth knocked out; luckily it was a baby tooth so it didn't really matter. I mostly spar with gloves these days and try not to get into fights, so no bare-knuckled punches to the face recently.