For the past month or so, Krystal WILL NOT let me brush her teeth, at all!

usually, i give her her toothbrush, and while im brushing mine, she has a chew adn tries to copy me, i say 'good girl, can mummy have a go' and she would let me very quickly brush her teeth.

now, i manage to get one or two bruches of the front teeth, then she closes her mouth and wont let me back in with the brush!

im getting worried that her teeth arent getting cleaned properly.. any other ideas??