Hi E.,
Actually you don't even really need toothpaste when you brush. Toothpaste is really a modern invention because when we clean something we like to use "soap" or we don't feel like it got clean. In fact, they have done some studies that people using lots of toothpaste brush LESS effectively because they think the toothpaste is "doing" something.
Yes - toothpaste has flouride. But most of the time your city water supply has flouride, so you don't even need the flouride in the toothpaste.
Just teach her how to brush correctly - brush for 2 minutes total using small circles at a 45 degree angle to the gum getting every tooth. Have her rinse with water before and after she brushes. her saliva will do the rest!
Also - most dentists recommend SUGAR FREE gum containing xylitol (like Trident) after you eat if you aren't able to brush. This stimulates the saliva which breaks down the plaque and removes it from your teeth.
If you don't have gum you can also use a piece of string cheese. In fact for cavity prone kids dentists will sometimes recommend they chew a piece of string cheese at the end of every meal - again it stimulates saliva production which changes the ph in your mouth and breaks down the plaque.
Thanks!