Well, Vegas and Orion each show one tooth on a daily basis. Opposite teeth. Vegas's right bottom sticks out and Orions bottom left. Very occasionally will Vegas have them both out. This is BAD news. It means he's playful and he wants to bite something. It's best to have a VERY durable toy close by.
Ha ha - my answer would have to be "all of the above" too. It just depends on how Hoagie's jowls are hanging LOL! His tongue sticks out most of the time.
Molly is a two toofer. Tidus is usually a one toofer. Yuna and Mandy only show their teef when they are at attention, like for meals or giving pets and treats. Jesse has no underbite so she is a no-toofer! Zip, ziltch, nada.
Linus never has his teeth out but on a very, very rare occasion, a single toof will appear. Truman usually has both toofs out. Bentley NEVER showed a tooth!
Winston's dont show at all. Hitch and Layla show one...but when she is trying to be extra cute she gets both teef out!!! It pretty much works everytime!
All the above also, mostly two, then sometimes one if his lips are dry, the only time there is none is when his tongue is sticking out or he is curling his bottom lip to give me the "chewbacca growl"!!