There are some toothpastes for babies that have no flouride in them. I found one at the shops & that is what I use with Matilda.

Matilda still has bouts of it, but we brush our teeth now at the same time in her bathroom & let her have a go, if she doesn't brush them we take our "special" brush out and do it ourselves (she has 4 toothbrushes but one is a Pooh one we keep for our special brushes).