Otherwise known as "the dentist" or "the dental hygienist", the oral hygienist is the lost art of giving two guys head at the same time, in the sense that the multiple penises represent the dental tools.
Guy 1: dude i totally had a three way last night with this random dude and this chick
Guy 2: oh nice... i think... you didn't cross swords did you?
Guy 1: Are you kidding me, we gave her the oral hygienist, she totally got the fluoride treatment.
Guy 2: nice.