The timeline for teeth

Posted on August 20, 2021 in General oral health

Father and son running in yard outsideYour teeth do more than give you a nice smile — they also work together to help you chew and speak properly as well as shape the appearance of your face.

Did you know your teeth started to develop before you were born? Here’s how teeth develop and grow from infancy through childhood. 

Teeth before birth

The soft tissues of teeth start to form just six to eight weeks into pregnancy. After three or four months, the hard tissue begins to develop. By the time a child is born, the crowns of 20 baby teeth are nearly completely formed. They usually aren’t visible though because they haven’t emerged from the jawbone.

Occasionally a child has one or more teeth showing at birth. In 1990, an infant in the U.K. was born with 12 teeth!1

Hello, baby teeth

Gradually, the teeth that formed under the gums begin to emerge. Baby teeth, also known as primary teeth, generally begin to show up somewhere between six to 12 months after the child is born. By the time a child is 3 years old, usually all 20 baby teeth have erupted — with 10 in the upper jaw and 10 in the lower jaw. 

Primary teeth typically emerge in this order:2

  • Eight incisors (front teeth) from 6 to 16 months old, usually beginning with a middle tooth on the lower jaw
  • Four first molars (near the back of the mouth) from 13 to 19 months old
  • Four canines (pointed teeth, also known as cuspids, next to the incisors) from 16 to 23 months old
  • Four second molars (at the very back of the mouth) from 23 to 33 months old

Baby teeth are generally smaller than the adult teeth that will replace them. Growth of the jawbones will typically allow space for permanent teeth. Check with your dentist or orthodontist around age 7 to determine if early orthodontic care would be beneficial.

While they may only be temporary, it’s important that baby teeth be kept clean and healthy. Baby teeth help children chew easily and speak correctly and help maintain space for the permanent teeth. Healthy teeth also keep children from experiencing mouth pain and cavities. A decayed baby tooth could cause an infection that damages the permanent tooth developing underneath.

In addition to daily oral hygiene, make sure your child visits the dentist regularly. The first visit should occur after the first tooth emerges or no later than their first birthday.

Bye, bye, baby teeth

As their roots start to dissolve, baby teeth fall out. They are usually lost in the same order in which they came in — beginning with the incisors (front teeth) around age 6. All incisors are usually lost by age 8. The first molars are generally lost between ages 9 and 11, with the canines and second molars following shortly after. By age 12, all baby teeth have typically fallen out.

Make room for adult teeth

As baby teeth fall out and the child’s jaw grows, there is room for adult (permanent) teeth to push up. People have 12 more adult teeth than baby teeth, for a total of 32 permanent teeth — 16 upper and 16 lower.

In addition to adult versions of baby teeth, permanent teeth include eight bicuspids (premolars) between the canines and molars, and four third molars (wisdom teeth) at the back of the mouth. Although some people never get their wisdom teeth or are missing at least one of these third molars.

Adult teeth usually emerge at the following ages, completing your permanent teeth by around age 21:

  • First molars from ages 6 to 7
  • Incisors from ages 6 to 9
  • Canines from ages 9 to 12
  • Premolars from ages 10 to 12
  • Second molars from ages 11 to 13
  • Third molars (wisdom teeth) from ages 17 to 21

Sealants can help protect permanent teeth from decay.  Sealants are thin plastic coatings that are applied to the chewing surfaces of molars and should be applied as soon as the permanent molars emerge.

In addition, you can help keep your child’s teeth healthy for a lifetime by practicing good oral health habits. Brush twice a day for two minutes each time, floss daily and visit your dentist regularly.