Teething, the process of baby (primary) teeth coming through the gums into the mouth, is variable among individual babies. Some babies get their teeth early and some get them late. In general the first baby teeth are usually the lower front (anterior) teeth and usually begin erupting between the age of 6-8 months. Children's teeth begin forming before birth. As early as 4 months, the first primary (or baby) teeth to erupt through the gums are the lower central incisors, followed closely by the upper central incisors.Although all 20 primary teeth usually appear by age 3, the pace and order of their eruption varies. .
Permanent teeth begin appearing around age 6, starting with the first molars and lower central incisors. This process continues from childhood into early adolescence. By the time kids turn age 13 to 14 most adult teeth should be present in the mouth. Teens and Adults have 28 permanent teeth, or up to 32 including the third molars (or wisdom teeth).