Baby teeth don't stick around for very long. Between the ages of six and twelve, baby teeth fall out and are soon replaced by their permanent successors. Baby central incisors last a mere six to seven years, and molars and canines last an average of ten years. What's more, those twenty dainty baby teeth are replaced by twenty-eight larger teeth.
A Confusing Process
As a parent witnessing this change occur in your own child, you might be wondering what the point of baby teeth is. If they are going to fall out in a few years anyway, why bother having them at all? Wouldn't it be simpler just to grow the permanent set of twenty-eight teeth? Well, as it turns out, there is a very simple—but important, reason for this process.
Smaller Jaws Need Smaller Teeth
Although your baby needs teeth to transition from liquid to solid foods, teeth also serve several other important functions. Teeth help babies learn to form words from as early as eight months. Moreover, though baby teeth may be small, they help to develop the facial muscles of babies and toddlers. Facial muscles are important for speech, facial expressions and appearance.
Adult teeth are larger, more numerous and they can withstand a lot more than baby teeth. However, since the jaw of a baby or toddler is much smaller than that of an adult, adult teeth would simply be too big. Therefore, baby teeth are essentially training teeth. They provide the developmental benefits a child needs until that child's jawbone is ready for their adult teeth.
Humans Are Diphyodonts
Unlike humans, many animal species, such as sharks, crocodiles and geckos, have an unlimited number of teeth. This makes them polyphyodonts. In contrast, humans and many other mammals, such as cats, dogs and apes, are diphyodonts. This means they start out with a baby set of teeth before progressing onto their final set of permanent teeth.
So, why can't humans replace their teeth over and over? Wouldn't that be far simpler—and far less costly in terms of dental bills? Perhaps, yes, but eating would be much less enjoyable. You see, polyphyodonts tear and shred their food. Humans, on the other hand, can tear, grind and crush their food. If you were a polyphyodont, mealtimes would create quite a mess!
A baby's first set of teeth is vital to their development. That's why it is important that you help them to brush their teeth morning and night until they are about six or seven. Also, make sure to take them to their dentist for their annual checkup.