I love this answer, b/c I had a dentist once that said "There are two kinds of mouths--gum problems, or cavities." I loved the simplicity of this, and the way he said it all deadpan, but everyone I told thought the guy must be a terrible dentist for boiling things down this way! He wasn't great, imo--not the best nor the worst I've had--but I'm glad you've confirmed what he said.