I guess the one thing that is glaringly obvious to me is that, even though it's a profile, you need to make it three-dimensional. This is most obvious with the mouth where only one side of the teeth is visible. Look at pictures of similar animals and you'll find that the teeth show through because they aren't exactly even. The eye is also a little dull and expressionless. Even basic images of animals should convey some form of emotion or tension.
You did a very good job on the textures of the tongue and the skin connecting the dragon's jaws, btw. The details are fantastic and fairly realistic. Also, kudos on sticking with that texture of the scales and being consistent, I probably would have gotten bored with it.
sweatdrop The closest thing to dragons that I've ever drawn are wolves, so unfortunately I can't give you any more specific critique than that.
Edit:
Picture of dinosaur skull with similar teeth