I brush my toddler's teeth 2x per day with a tiny amount of toothpaste as recommended. We use a standard kids toothbrush, not an electric one.
We sing the ABC song while I'm doing it, to keep her entertained and to develop a ritual so she gets a sense of how long it takes. That makes it on average a 25 second brushing session...and sometimes she shuts her mouth and says "no" at about the time we get to the letter "Q" after which I don't push her to keep letting me brush. I know that for adults it's recommended to brush for 2 minutes. It seems like toddler torture to brush her teeth for that long.
Knowing that problems with toddlers' teeth is on the rise, and that I have a family history of bad teeth and cavities, I want to be sure to be doing the right thing for her teeth now as well as helping her form good habits as she grows older. I also want to keep brushing time fun, without making it into a torture session.