Mom wants me to get a new toothbrush, but I LOVE my old Spider-Man toothbrush! How can I convince her that Spidey rules?

Mom knows best. You need a new toothbrush every few months, or whenever your old brush gets frayed. Old toothbrushes don't clean teeth as well and can miss spots. Maybe you and Mom can shop together for a new Spider-Man toothbrush!

Why does Dad say that junk food will give me cavities?
Why do I have to brush my teeth?
I want a SpongeBob SquarePants toothbrush, but my sister says Barbie toothbrushes are better. Do I have to listen to her?
How often should I brush my teeth?
Why do we use toothpaste?
What is the best toothpaste?
What is fluoride?
Help! I'm supposed to floss, but I can't reach my back teeth! What do I do?