Being mammals, we sport two sets of teeth, the primaries and the permanent. Assuming Mom has already lent strength to her baby’s teeth during pregnancy—beginning from week seven of prenatal life—teeth grow through two stages. In the first permutation, teeth take shape; in the second, the cells are actually transformed to perform different functions. All this is percolating as you enjoy pickles and ice cream.
When your baby is born, you won’t see teeth, but they’re there. Enamel and dentin are still forming in the jaw and, in a matter of months, the teething process is well underway. The root, however, will take another few years to be firmly established.
Make no mistake about the role of “baby” teeth—they are indispensable. The front teeth are going to be around for about 5 or 6 years, the molars for a decade. And they clearly map the route for permanent teeth. Interrupt this path with missing teeth, and your child may be set for life with a bite just out of alignment, or crowded dentition.
The upper primaries will usually hang on longer than the lowers, but keeping them all shipshape is critical to the health of permanent teeth. With luck and hygiene, your child will keep a full set of 32 permanent teeth for 90% of his or her life. Keep your fingers crossed and the pickles handy.
There are 20 primary teeth, 10 in each jaw. By the time the child is 2 or 3, a complete set should arrive. As the jaw continues to grow, you may notice some gaps which will probably resolve later on.