I work at a vet clinic and have for over 4 years. You have nothing to worry about some dogs do that. One of mine does that for no reason sometimes. It's a nerve around there and some dogs when they get older it does that but no need to fear wait til it's cold it's kinda funny I think.hahah
My Dog's Lower Jaw Has A Quiver, It Seems To Happen When She Gets Excited About Something, She Is 7 Years Old. It's Been Going On For 2 Weeks Now, Any Ideas About Why This Is Happening?
I do not pretend to know why some dogs develop this trait when they are excited about food or walks etc. One of mine did it to the extent that his teeth would chatter. It seems to be quite harmless, he lived to a ripe old age.
If you notice confusion, restlessness or anxiety during this or if the little one starts whining like pain whining then you might have some concern. These could be signs of epilepsy or dental disease. However both of these are very managable. If you don't see these other symptoms there is probably nothing wrong. Sometimes when a dog is skinny(not starving) the nerve endings are a little closer to the surface so a little excitement stimulates the muscle. My little girl Glitz does the same thing and she's still the same sweetheart she's always been.