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 ...

Strengthening jaw muscles can be useful for many reasons, such as improving facial aesthetics and providing better chewing ...

That slightly open mouth while concentrating. The subtle parting of lips during sleep. The tendency to breathe through your mouth instead of your nose during exercise. These seemingly innocent habits ...

Falling asleep with our mouths open happens to all of us and many think it isn't such a big deal. However, there are some eye-opening things connected to open-mouth sleeping. Our facial muscles tense ...

Mark Gurarie is a writer covering health topics, technology, music, books, and culture. He also teaches health science and research writing at George Washington University's School of Medical and ...