A friend of a friend has just bought a 6 month old Shih tzu with a crooked mouth; I've only seen a photo but looks like the whole bottom jaw is slightly off-set to the right and there is 1 canine tooth showing; anyone have any experience/ thoughts about what could cause this? conformation? too many teeth?!

Has a protruding bottom jaw as well, common in the breed though I understand

I don't know anything about Shih Tzus, but I breed Persian and Exotic cats which are flat faced and twisted jaws is common in them and it is genetic. It's got so that I can tell already at birth, before there even are any teeth, if the jaw is going to end up that way or not. I've never had any have any actual problems from it, they eat well etc, but obviously they should not be bred from. I'd imagine it would be much the same in dogs -but let's hope somebody who knows the breed comes along to say for sure.

Thanks for that can't find out much online but I think a visit to the vet is in order!

Persian and Exotic cats

I had a persian cat with this - He was bought as pet only (I had no interest in breeding cats anyway) so I had to get him neutered (as I would have done with any male cat) as one of the conditions of the purchase.

It never cause him any problems and you couldn't really tell unless you pulled his lips right back - Which he didn't appreciate I can tell you!

Hope you manage to get to the bottom of it and hope it doesn't cause him any problems...

I've seen a few over the years and have to say their mouths are not the best.  Not sure if it is a breed thing though?  I suppose the thing though is when you have breeds that have to have perfect scissor bites something different does look strange.