
Loads of puppies look like their canines are slightly inverted especially in medium length faced breeds. If they were really inside I would be concerned. It is quite common for it look like that with scissor bite breeds. I have seen it often not only in my own breed and they have all had perfect mouths.
HOWEVER :-)
There is a issue a heriditary malformation though called Base Narrow Canines I can't remember what breeds but there is one or two where it is seen more than the average , it may be Irish wolf hounds but someone will correct me. PLEASE DO :-)
One thing I would say it if you like the pup run it on. :-)