Well does she like the taste of her tooth paste? You could try buying her a different kind. My girls love the kind with Tinkerbell on the bottle. Or you could take her to the store and let her pick out her very own new tooth brush. They have cute kid electric ones that might appeal to her. Sometimes kids just go through little phases and power struggles. So don't give into her (which it sounds like your not) but she should grow out of it. You could also try rewarding her for when she is good about brushing her teeth. Like start a sticker chart. When she doesn't fight you she gets a sticker and if she fills up a week of stickers then she can get a surprise....like a new book, toy, crayons, a piece of candy etc. That might help her want to be better. Hope this helps.