Pacifiers come in many shapes and sizes. Orthodontic pacifiers have been scientifically designed to support the shape of babies' developing palates and jaws. The flattened shape not only simulates the shape of a mother's nipple when flattened in the mouth, but also encourages the most natural sucking action to help proper oral development.
Studies indicate that children who use orthodontic pacifiers have a smaller chance of developing an open bite or an overbite than those who use conventional round pacifiers.This difference is hard to demonstrate, though, because neither type tends to cause problems unless sucked intensely for years.
It's more important to choose a shape your baby enjoys. Babies can have quite strong preferences on these matters, and ultimately they will decide which one is for them. Because you can't know beforehand which your child will prefer, you might want to get several different types to try out.
You can also choose between latex or silicone pacifiers. Latex nipples are softer and more flexible, which may appeal more to a newborn, but they don't last as long. Silicone nipples are firmer, hold their shape longer, and are easier to clean.
While babies decide which pacifiers they like, you decide which are safe and convenient. Choose sturdy pacifiers with a shield that is at least 1 1/2 inch across to prevent choking. I like dishwasher-safe pacifiers for extra convenience, but the choice is yours.
Another important feature to look for is vented shields to protect the skin around your baby's mouth. Without them, saliva can collect behind the shields, irritating the skin and causing a rash.