Toothpaste has fluoride in it. Fluoride helps strengthen your enamel so you don't get cavities. You actually do not need to use toothpaste. The point of brushing is to get the bacteria (plaque) off of your teeth. Some people are more prone to cavities so it is a good idea to use it. They do sell none fluoridated toothpaste if you would prefer to use that. All it will do is freshen your breath and some have whitening components.
