Now, I have the urge to share a secret with you, dear David.
This knowledge has never before slipped to the non-dental world:
When we first enter dental school, one of the basic learnings is the dentist´s ABC.
The dentist´s ABC starts with the letters W, Y, S.
Somehow, I don´t know how, you seem to have gained this lecture, maybe in some supernatural way.
WYS stands for Wipe Your Shoes!
So, yes, of course, I do wipe my shoes thoroughly and with my whole heart, before I step into other people´s mouths.
I hope, this secret revelation will give a little relief to the world.