Adults are supposed to have 32 permanent teeth, including wisdom teeth. Children have a smaller set of 20 baby teeth. The number you actually have at any point in your life depends on your age, whether your wisdom teeth came in, and whether you’ve lost any teeth along the way.
Children’s Teeth: The First 20
Baby teeth (also called primary or deciduous teeth) start appearing around 6 months of age, and most children have their full set of 20 by age 3. These 20 teeth include eight incisors (the flat front teeth), four canines (the pointed ones), and eight molars (the wider teeth in the back used for chewing). Children don’t have premolars, which is one reason their set is smaller than an adult’s.
Baby teeth aren’t just placeholders. They guide the permanent teeth into position as they develop beneath the gums. When a baby tooth falls out too early from decay or injury, the surrounding teeth can drift into the gap and crowd out the permanent tooth trying to come in.
Adult Teeth: The Full 32
Permanent teeth begin replacing baby teeth around age 6 and continue arriving through the early teens. The full adult set of 32 breaks down 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, used for tearing food
- 8 premolars: sitting between the canines and molars, with flat surfaces for crushing food (these are new, with no baby-tooth equivalent)
- 12 molars: the large, flat teeth in the back of the mouth, including four wisdom teeth
The premolars and the second set of molars typically finish coming in by age 12 or 13. Wisdom teeth are the stragglers, often not erupting until the late teens or early twenties. By around age 21, the average person has all 32.
Wisdom Teeth and Why Your Count May Differ
Wisdom teeth, or third molars, account for the last four of those 32 teeth. You have one in each corner of your mouth: upper left, upper right, lower left, and lower right. But not all of them necessarily erupt. Some stay trapped beneath the gum (impacted), and many people have them removed because of crowding, pain, or infection risk.
If you’ve had all four wisdom teeth extracted, your working total is 28. That’s perfectly normal and very common. Some people are born without one or more wisdom teeth entirely, meaning their body simply never developed them. So if your dentist has told you that you have 28 teeth and no wisdom teeth to worry about, nothing is wrong.
Having More or Fewer Teeth Than Normal
Not everyone follows the textbook count. Roughly 3.5% to 8% of the population is born missing one or more permanent teeth, a condition called hypodontia. Wisdom teeth are the most commonly absent, but premolars and upper lateral incisors can also fail to develop. On the other end, about 1% to 3% of people develop extra teeth (hyperdontia). The most common extra tooth, called a mesiodens, grows between the two upper front teeth. Around 90% to 98% of extra teeth appear in the upper jaw.
Extra teeth in baby teeth are rarer, showing up in less than 1% of children. In most cases, a dentist spots these variations on routine X-rays and decides whether they need treatment based on whether they’re causing crowding or other problems.
How Many Teeth Older Adults Actually Have
The “supposed to have” number is 32, but reality looks different as people age. According to the National Institute of Dental and Craniofacial Research, adults 65 and older have an average of 20.7 remaining natural teeth. Among those 75 and older, the average drops to 19.5. About 17% of seniors have no natural teeth at all.
The factors behind tooth loss go well beyond aging itself. Smoking has one of the strongest associations: current smokers over 65 retain an average of only 15.8 teeth, compared to 21.6 for people who never smoked. Nearly 43% of older adults who smoke have lost all their teeth. Income and education show a similar pattern. Seniors living below the poverty line average 16 remaining teeth, while those with higher incomes average 22.2. These gaps reflect differences in access to dental care, preventive habits, and overall health rather than any biological inevitability.
Tooth loss at any age is driven primarily by gum disease and untreated cavities, both of which are largely preventable with consistent brushing, flossing, and regular dental cleanings. Keeping all 28 to 32 teeth for life is a realistic goal for most people, not an idealistic one.