Other Research

Thumb sucking and sippy cups can cause similar problems.

"If a child goes from the breast or the bottle to a sippy cup, they tend to drink it as if it were a bottle. They lie back or tip their neck in the usual manner, so it's almost like drinking a bottle,they have a hard object or spout with various shapes depending on the type of cup, and their bodies are tipped back. This hard object or spout misplaces the tongue and pushes the teeth out as the thumb can."

Steer clear of sippy cups and use straws instead.

Today, we are kind of spoiled and not as used to a mess when a cup spills, but that's a mistake," Holtzman says. Instead of cups with spouts, use cups with straws or simply place a straw in a paper or plastic cup.