Interesting find Richie ... suuuure, things like this start turning up AFTER I leave!
I find myself wondering how you came across a veritable needle in a haystack of a wreck like the Eagle - Steve must have been absent on that dive, so you were less preoccupied!
As far as what that might be just a wild-ass guess, but maybe a barb from a stingray or some other spiked species? Looks possibly more like that than a tooth ...