Orbicularis Oris

Or lip muscles. Also known as the 'kissing muscle' and the bane of my working day today.
As if fighting tense lips wasn't enough, a couple of patients unleashed a tense lip and tongue combo....my poor hands :-(

I know people aren't fond (for want of a better word) of the dentist, but seriously; treatment would be a lot quicker and easier if they'd just open their mouths!
Say ahhhhh!