This is actually really impressive. Would you mind telling me what you used to draw this? I'm still using paint on my computer, which has produced less than desirable results. And since you say it's bugging you, it'd probably be easiest to widen the lower jaw to make it seem to fit the upper jaw a bit better, but like I said before, it seems great to me.

This was done on a Galaxy note 10.0 using Autodesk sketch pro (or something along those lines...) It's fairly decent to use but needs a long, LONG while to get used to, due to its awkward pressure sensitivity (even touching the screen with the side of your hand resizes the imager, making thing very annoying at times) and its lack of most effects (like a blur tool... but it does have ways to work around it, again, with practice) XD

I remember back when I was still using paint and mouse (not that long ago, TBH). Trust me, it makes you appreciate decent programmes a lot more when you get them! When not using a Galaxy I use Gimp 2. If Im not mistaken it is free and pretty good.
http://www.furaffinity.net/view/11739268/ That pic was made in Gimp without a tablet and only using a mouse, to show you what you can do on it.

Thank you very much for your comment and I hope that this helps you in some way :3

*Edit... forgot to hit reply... oops...

Dem hands <3 TEACH ME SEMPAI

Step wun: look at ur hands drwr ur left hands
steb bee: loook at ur rite hand hand and curse the world as you reelise u cny drawer wit ur left handhand
- take up drinking and cri everytim

10/10 would art again