In the TV Universe, various parts of our body are independently alive as well. We saw in that Super Bowl ad for CareerBuilder.com a girl's heart leap out of her chest and go in to tell the boss "I Quit!" Over in the Tooniverse, a man's stomach (with the voice of Gene Wilder!) engaged in a point/counterpoint debate with its "owner" in an ad for Alka Seltzer.
Now, in a blipvert for Dentek Nightguard, we learn that each of our teeth has its own individual personality.
When we see people walking down the street talking to themselves, could they be having conversations with their teeth?