Because of my Montessori training I have always cringed (and been nearly ready to contact CPS) every time I hear a dental hygenist recommend placing child on the floor, straddling them, holding them down, prying open the mouth and brushing the teeth. Simply not the way I was trained to approach children.
Here is a video of my chosen method. I follow the child, keep it fun, give choices, give respect and teach independence. Hopefully, Olivia will continue to find brushing her teeth a good thing. So far she enjoys it.