We may think of baby teeth as being in the mouth one day and gone the next, but they actually live out quite a journey that starts even before the child is born. Tooth buds, the precursors to teeth, begin developing when the baby is still in the womb. And, in fact, one in 2,000 newborns will have a few already-developed baby teeth at birth [source: Baby Center]. Generally, though, teeth start surfacing when a baby is 3 to 12 months old. They usually start in the bottom-front of the mouth and begin working their way to a full set. Then, by about age 6, the permanent teeth are ready to slowly start pushing the baby ones out.
Keep an eye out for wiggly teeth during this age, because you'll probably want to hang onto your child's first tooth once it falls out. For starters, you'll need to leave it for the Tooth Fairy -- that is, unless you're from a European or Latin American country where a magical mouse steals the tooth overnight [source: McDonald, et. al].
What you do with the tooth once the mythological creatures give it back is up to you. You might want to make a special pocket in your scrapbook for it. Some parents have the tooth dipped in silver or gold in order to make it a necklace or key-ring pendant. If you prefer for it to have its own holding place, many jewelers sell specialty boxes for keeping a child's first tooth. Depending on your decorating taste, you can find these keepsake holders in anything from antique Limoges boxes to sterling silver (and just about everything in between). You can even find a corresponding case to contain a lock of hair from your baby's first haircut.
Of course, not everyone wants to commemorate their child's first tooth by keeping it. In the Middle Ages, it was popular to burn baby teeth in a fire. This had the rather macabre purpose of saving a person the trouble of having to search for their teeth in the afterlife. A more lighthearted custom still practiced by many cultures is that of throwing a baby tooth over or under the house [source: Beeler]. (Usually, teeth from the lower mouth are thrown above the house, and those from the top are thrown under.)
If you'd like to know more about family traditions or children's dental care, turn to the next page for lots more information.