Children get 20 baby teeth in total. These primary teeth come in gradually during the first few years of life, then fall out one by one starting around age 6 to make room for the 32 permanent teeth most adults end up with. Understanding the timeline helps you know what to expect at each stage.
The 20 Primary Teeth
A child’s mouth is divided into four quadrants: upper left, upper right, lower left, and lower right. Each quadrant holds five baby teeth, giving a total of 20. The breakdown looks like this:
- 8 incisors: the four front teeth on top and four on the bottom, used for biting
- 4 canines: the pointed teeth next to the incisors, one in each quadrant
- 8 molars: two in each quadrant, the flat teeth in the back used for chewing
You’ll notice there are no premolars in a baby’s mouth. Those only show up as part of the permanent set later on. Baby teeth are also noticeably smaller than adult teeth, with thinner enamel and less dense inner layers. That thinner enamel is one reason cavities in baby teeth can spread quickly.
When Baby Teeth Come In
Most babies get their first tooth between 6 and 12 months of age. The lower central incisors (the two bottom front teeth) typically appear first, usually between 6 and 10 months. From there, the teeth generally arrive in this order:
- Upper central incisors: 8 to 12 months
- Upper lateral incisors: 9 to 13 months
- Lower lateral incisors: 10 to 16 months
- First molars: 13 to 19 months (upper), 14 to 18 months (lower)
- Canines: 16 to 23 months
- Second molars: 23 to 33 months
By roughly age 3, most children have their full set of 20 teeth. These ranges are wide, so a baby who doesn’t have a tooth at 10 months isn’t necessarily behind. In rare cases (about 1 in 3,000 births), a baby is actually born with one or more teeth already in place. These “natal teeth” can sometimes cause feeding difficulties or tongue irritation and may need to be monitored.
Why Baby Teeth Matter More Than You’d Think
It’s easy to dismiss baby teeth since they’re temporary, but they serve several important roles. They’re essential for chewing food properly during the years when kids are growing fastest. They also play a direct role in speech development. Children who lose front teeth early due to decay can struggle with sounds like “th” and “la,” sometimes enough to need speech therapy.
Baby teeth also act as placeholders. Each one reserves a spot in the jaw for the permanent tooth forming underneath it. When a baby tooth is lost too early, neighboring teeth can drift into the gap and block the permanent tooth from coming in straight. That’s a common cause of crowding and misalignment later on.
When Kids Lose Their Baby Teeth
Children start losing baby teeth around age 6, though some don’t begin until closer to 7. The teeth fall out in roughly the same order they arrived. The lower central incisors go first, followed by the upper central incisors, then the lateral incisors, first molars, canines, and finally the second molars. By age 13, most children have lost all 20 baby teeth and replaced them with permanent ones.
Between ages 6 and 12, kids are in a stage called mixed dentition, meaning they have a combination of baby teeth and adult teeth in their mouth at the same time. This is completely normal and can look a bit awkward, especially when large permanent incisors come in next to small remaining baby teeth.
The 32 Permanent Teeth
The full adult set includes 32 teeth: 8 incisors, 4 canines, 8 premolars, and 12 molars (including 4 wisdom teeth). The premolars are new additions that replace the baby molars, and the permanent molars erupt behind the last baby teeth rather than replacing anything.
Wisdom teeth, the third set of molars, typically come in during the late teens or early twenties. Many people have them removed, and some are born without one or more wisdom teeth entirely. If you’ve had your wisdom teeth taken out or never developed them, you’ll have 28 teeth instead of 32.
When the Count Is Different
Not every child ends up with exactly 20 baby teeth or exactly 32 permanent teeth. Some children are born missing one or more teeth, a condition called hypodontia that affects 2 to 10 percent of the population in the permanent set. Others develop extra teeth (hyperdontia), which occurs in roughly 0.1 to 3.8 percent of people. Both conditions are usually identified on dental X-rays and can be managed with orthodontic planning.
The American Academy of Pediatric Dentistry recommends scheduling a child’s first dental visit within 6 months of the first tooth appearing, and no later than 12 months of age. Early visits help catch any anomalies in tooth count or development before they become bigger issues.