Eruption of your Child’s Teeth
Teeth begin forming while you are still in the womb. The first primary (or baby) teeth erupt through the gums as early as 3-4 months. These first teeth to erupt are usually the lower central incisors. The upper central incisors will normally follow soon after. All 20 primary teeth have usually appeared by age 3, but the order of their eruption can vary as can the timing.

Permanent teeth begin forming near birth and erupt into the mouth around age 6. Like the primary teeth, the first permanent teeth are usually the lower central incisors, followed closely by the permanent molars. Many parents are surprised to learn that the permanent molars erupt behind the last primary molars without losing baby molars to make room. Adults have 28 permanent teeth, or up to 32 including the third molars (or wisdom teeth).

The transition from all primary teeth to all permanent teeth occurs over many years and usually in two time periods. The first period is from 6 years to 8 years as the incisors are replaced and the first permanent molars come in. The next period begins around 9 to 10 years of age and continues until your child is about 12 years old; during this period the canines and primary molars are replaced.

We use the simplified phrase: lose the first 8 teeth by 8, and the next 12 by 12.

If you prefer to watch the teeth erupt instead of looking at a chart or reading about it, try this visual: