I've had the "lost my teeth" dream a few times. Seriously sucks.
I've also gotten pretty good at realizing when I'm dreaming. Most of the time, it's pretty awesome, because you can just do whatever you want. Had an excellent flying car/spiderman dream just last night.
But sometimes when you realize you're dreaming, you can't control stuff, and then you try to wake up, which is practically impossible even though you can half feel yourself trying to move your arms and stuff in real life, but you're all "sleep paralyzed" or whatever they call it. Really freaky, because you feel trapped.