I've heard that it isn't necessary to use toothpaste on a child younger than age 2.
That's correct. This is a crucial stage in tooth development. The permanent teeth are forming inside the jaws; if they're exposed to a large amount of swallowed fluoride, they can develop with unsightly stains. This is a common occurrence among young children who don't spit out toothpaste during and after brushing. With children younger than 2, it's recommended that you use plain water or a tooth and gum cleaner that doesn't contain fluoride. When your child's older, limit the amount of toothpaste you use to less than the size of a pea until he understands that he shouldn't swallow it.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.