Where There Is No Dentist 2012 43
How Often Do Teeth Grow In?
A child gets two sets of teeth. The first set, baby teeth,
starts to grow when the child is a baby. The second and
last set grows in at school age. They are the permanent
teeth. Permanent teeth should last a lifetime.
A child grows his first baby tooth at about 7 months of
age. It is usually a front one.
A baby who is poorly nourished, however, may not grow his first tooth until
later. Do not wait for the first tooth before giving him the extra soft food he
needs to grow and stay healthy.
The remaining baby teeth grow in over the next 24 months. By the time the
child is 30 months old, there will be a total of 20 baby teeth in his mouth,
10 on top and 10 on the bottom.
Most permanent teeth form under the baby teeth. When the child is
between 6 and 12 years old, the permanent teeth push against the roots
of the baby teeth, making them fall out. Not all of the baby teeth fall out at
once. One tooth at a time becomes loose, falls out, and then is replaced with
a permanent tooth. The new tooth may not grow in immediately. Sometimes
2 or 3 months pass before the new tooth grows into the space.
In the 6 years between ages 6 and 12, the 20 permanent teeth replace the
20 baby teeth. In addition, 8 other teeth grow in behind the baby teeth.
At 6 years, the 4 first permanent
molars start to grow in at the back of
the mouth. This means an
8-year-old child should have
24 teeth, or spaces for them.
At 12 years, the 4 second
permanent molars grow in behind
the first molars. This means a
14-year-old child should have
28 teeth, or spaces for them.
Between 16 and 22 years, the 4 third
permanent molars grow in. This
means that an adult usually has a
total of 32 permanent teeth: 16 on
top and 16 on the bottom.*
*(Note: the third molars often do not grow in correctly. This is a very common cause of tooth
pain. See page 66.)