Lockjaw (trismus) is a painful condition that limits your ability to open your mouth all the way. It occurs when the muscles you use to chew spasm, meaning they can’t relax completely. The term ...

Dear Eric: I play cards weekly with a group. One of the women sometimes chews gum during our games, noisily and with her mouth open. This is worse than fingernails on a chalkboard to me. Why do ...

Dolphins living in captivity often make an open-mouth facial expression while playing with each other. Zoomarine, Italy Bottlenose dolphins “smile” at each other while playing, making open-mouth ...

Dolphins are known for what appear to be big, contagious smiles. But do they actually, well, smile? The answer, according to a new study of dolphin play, is a resounding “maybe.” Dolphins use their ...

DEAR ERIC: I play cards weekly with a group. One of the women sometimes chews gum during our games, noisily and with her mouth open. This is worse than fingernails on a chalkboard to me. Why do ...

Having your mouth taped shut is the stuff of nightmares — but some people are doing just that to themselves. And in an attempt to sleep better, no less. Doctors say don't do it. Some on social media ...