How Many Teeth Do Humans Have?

Adults have 32 permanent teeth — or 28 without wisdom teeth — and children have 20 baby teeth.¹ Kids start losing their primary set around age 6 as the permanent teeth come in.¹ This article breaks down the four tooth types adults have, when each one erupts, and what happens when teeth are missing or extra.

Tooth Count at a Glance

Group	Total teeth	Breakdown
Adults (with wisdom teeth)	32	8 incisors, 4 canines, 8 premolars, 12 molars
Adults (without wisdom teeth)	28	8 incisors, 4 canines, 8 premolars, 8 molars
Children (primary teeth)	20	8 incisors, 4 canines, 8 molars (no premolars)

Counts come from the American Dental Association’s eruption charts and the StatPearls dental anatomy reference.^1,2 Some people are born missing one or more permanent teeth, and others develop extra (supernumerary) teeth — see What If You Have Fewer Than 32 Teeth? below.

How Many Teeth Do Adults Have?

Adults have 32 permanent teeth: 8 incisors, 4 canines, 8 premolars, and 12 molars (including 4 wisdom teeth).^1,2 Each type does a different job:

1. 8 Incisors — Used to cut food
2. 4 Canines — Used to tear and grasp food
3. 8 Premolars — Used to crush and tear food
4. 12 Molars — Used to help you chew and grind food

How Many Teeth Do Kids Have?

Children have 20 primary (baby) teeth: 8 incisors, 4 canines, and 8 molars.^1,2 Primary teeth do not include premolars.

Primary teeth fall out as permanent teeth take their place. With the front teeth and premolar positions, the incoming permanent tooth pushes the baby tooth out from below. With the permanent molars, the new tooth erupts behind the last primary tooth, since no baby tooth occupies that spot.

What About Wisdom Teeth?

Wisdom teeth are the third molars — the last permanent teeth to come in. They erupt between ages 17 and 21, though some come in later.^3,4,16

When Wisdom Teeth Need to Be Removed

Wisdom teeth that don’t have room to erupt properly — growing in sideways, staying partly trapped under the gum, or pushing against the second molar — sometimes need to be removed. These problems can lead to pain, infection, decay, gum disease, cysts or tumors, or damage to nearby teeth.^4,5

Removal is usually unnecessary when a wisdom tooth is:⁶

• Healthy
• Fully erupted
• Positioned properly and biting against the opposing tooth
• Able to be cleaned daily

The decision is not always clear-cut. A 2020 Cochrane review found insufficient evidence to support routine removal of impacted wisdom teeth that are asymptomatic and disease-free.⁷ Your dentist or oral surgeon will weigh position, symptoms, and X-ray findings to recommend removal, monitoring, or another approach.^4,5,6

Caring for Baby and Adult Teeth

Children start dental visits when the first tooth comes in and visit by their first birthday.^8,9

When Does a Child’s First Tooth Erupt?

A child’s first tooth erupts around 6 months old. Most children have all 20 primary teeth by around age 3.³

Each child follows their own timeline, so a small lag isn’t a concern on its own. If a baby still has no teeth by 9 months, or if a specific tooth is more than a year behind the usual eruption range, ask the pediatric dentist.¹⁰ If needed, dental X-rays can help check whether the baby and permanent teeth are present and how they are developing.

Some children are congenitally missing a tooth, and others develop a supernumerary (extra) tooth, leaving them with fewer or more than the average count.^10,11

When Should Dental Exams Start?

According to the American Academy of Pediatric Dentistry (AAPD), a child’s first dental visit should happen when the first tooth appears, or no later than the first birthday.⁸ The CDC echoes the same first-birthday milestone.⁹

Brush your child’s teeth twice a day as soon as the first tooth comes in, and schedule that initial appointment.⁹

When Should a Child Begin Losing Their Primary Teeth?

The first baby teeth to fall out are the lower central incisors, around age 5 or 6. The primary first molars are usually lost between ages 9 and 11.³ Children lose all their baby teeth by around age 12.

When Do Permanent Teeth Start to Grow?

The first permanent teeth to come in are the central incisors and the 6-year molars, named for the age at which they typically erupt.³

The rest of the permanent teeth erupt between ages 6 and 13. Wisdom teeth, if they develop, come in between ages 17 and 21.³

What Are Over-Retained Teeth?

Over-retained primary teeth are baby teeth that don’t fall out when expected.^12,13 Common causes include:

• Tooth agenesis — the most frequent reason, in which the permanent successor never forms
• Ankylosis — when the root of the primary tooth fuses to the jawbone
• Infection
• Trauma
• Impacted permanent teeth

If your child’s baby teeth haven’t shed when expected, see a pediatric dentist and an orthodontist.^12,13

A healthy over-retained baby tooth can sometimes be kept into adulthood. The crown, roots, and supporting bone need to be sound, and the tooth must not cause functional or cosmetic problems.¹²

When a baby tooth is ankylosed, the orthodontist may recommend extraction. The call depends on factors including:

• Age at the onset of ankylosis
• Location of the affected tooth
• The child’s smile line
• The child’s dental development

What If You Have Fewer Than 32 Teeth?

Many adults end up with fewer than 32 permanent teeth. Wisdom teeth are absent or removed in many people, and teeth are also lost to decay, gum disease, injury, or extraction.^11,14 When permanent teeth never develop in the first place, the main developmental categories are:^11,14

• Hypodontia — one to five permanent teeth (excluding wisdom teeth) fail to develop. It is usually inherited and most frequently affects the upper lateral incisors and second premolars.^11,14
• Oligodontia — six or more permanent teeth (excluding wisdom teeth) fail to develop. It is rare and usually genetic.¹¹
• Anodontia — a complete absence of teeth. It is hereditary and rarer than hypodontia or oligodontia.^11,15

Congenitally missing teeth trace to a mix of genetic and environmental factors.¹¹ Reported associations include advanced maternal age, low birth weight, maternal smoking, and rubella exposure during pregnancy.¹¹ Hypodontia is slightly more common in females than males.¹¹

Treatments such as dental implants and dentures restore a partial or complete absence of teeth.¹⁴

Impact of Missing Teeth

Missing teeth affect chewing, speech, alignment, and confidence.¹⁴ Common consequences include:

• Difficulty chewing — Missing teeth make it harder to break down hard or crunchy foods, which can limit food choices and affect nutrition
• Speech changes — Missing teeth in the front of the mouth alter pronunciation and clarity of speech
• Dental misalignment — Neighboring and opposing teeth drift into the empty space
• Social and emotional impact — Missing visible teeth affect self-esteem and lead some people to avoid social situations

How to Restore Missing Permanent Teeth

Dental implants, dentures, and bridges are the most common restorations for missing permanent teeth:¹⁴

• Dental implants — Artificial tooth replacements surgically anchored into the jawbone
• Dentures — Full or partial sets of artificial teeth
• Dental bridges — Restorations that fill the gap left by one or more missing teeth
• Preserving baby teeth — Children are usually not candidates for permanent restorations, but a healthy retained baby tooth can sometimes be kept when the permanent successor is missing¹²
• Orthodontic braces and appliances — Braces close gaps by moving existing teeth into the open space

Timing matters in kids. Regular dental visits keep you and your child’s dentist on the same page about which option fits best and when to start.

When to See a Dentist

See a dentist or orthodontist if any of the following apply:

• A baby tooth still hasn’t fallen out more than a year past the typical loss age. The pediatric dentist will take X-rays to check whether the permanent successor exists and is positioned to erupt.¹²
• A permanent tooth seems to be missing. A dentist will use a clinical exam and X-rays to confirm whether the tooth is impacted, late, or congenitally absent, and discuss orthodontic or restorative options.^10,11
• A wisdom tooth is causing pain, swelling, or recurrent gum infection. An oral surgeon will evaluate position and symptoms with an exam and X-rays, then recommend removal, monitoring, or other treatment.^4,5
• Missing teeth are affecting chewing, speech, or self-esteem. A general dentist or prosthodontist will walk you through implants, bridges, dentures, and orthodontic options based on the gap, bone health, and budget.¹⁴
• A child has no teeth by 9 months, or a specific tooth is more than a year behind its eruption range. The pediatric dentist will check development and rule out conditions that delay or block tooth formation.¹⁰

Good day-to-day care — brushing twice a day, flossing, and routine cleanings — also protects the teeth you already have.¹⁷