“Behind every smile there's teeth.”

“A sociable smile is nothing but teeth.”

“Life is short. Smile while you still have teeth.”

“You can only hold a smile for so long, after that it's just teeth.”

“Back in the day they stole our smile, so we clothe our teeth in gold.”

“Behind a frowning providence
He hides a smiling face.”

“He was looking at her from behind the smiling that wasn't smiling but was something you were not supposed to see beyond.”

“The art of a diplomat is to conceal all turbulence behind his smile.”

“Leon regarded Archie with triumph, smiling almost grotesquely, a caricature of a smile really. Leon was not accustomed to smiling. But something else was behind the smile, behind those icy cold eyes, a smile that said he had not believed a word of what Archie had said. Which did not bother Archie in the least. The important thing was that Leon had chosen to pretend he had believed.”

“Hide your craziness behind a beautiful smile. That's all you need.”