My daughter took a header into the wall a few months ago at home and split her forehead open. Docs at the ER used dermabond, which is basically like a "medical-grade" super-glue. Doc said that most regular super glues have methyl alcohol in them, which can burn tissue. Medical grade glues are more expensive, but do not damage tissue and I guess are supposed to break down harmlessly.
They are very expensive though, so I just use super-glue to close flappers.
Echoing scheissami, I would not put it IN the wound, but would use it just to seal the flap (assuming it didn't rip off).