So Jessica Simpson, wow. Really?
I'll give her one thing, it certainly does take guts to go on national television and tell everyone you don't brush your teeth. Read the article here if you haven't. However, not only is it gross, it's hazardous to your overall health. Jessica says she uses Listerine and flosses, umm... great.
Flossing is essential to dental health. Good on ya there Jessica.
However, there is a reason that we dentists recommend brushing three times a day. Everything you eat and drink during the day touches your teeth, trapped food particles and sugar leads to decay. Invisible bacteria (plaque) also accumulates on your teeth. Brushing frequently removes the plaque, so that it doesn't harden into tartar. Tartar is more damaging to teeth, and much harder to remove. That "slippery" feeling that Jessica doesn't like actually indicates clean teeth, with an absence of tartar.
Brushing your teeth also helps to stimulate your gums, which can help prevent periodontal disease. Periodontal disease is a very dangerous on going health condition which has been linked to heart disease, diabetes, low birth weight and still born babies, aspirated pneumonia and in extreme cases, death.
Moral of the story; brush your teeth. You're cooler than Jessica Simpson.