How Many Teeth Do Adults Have? 32, 28, and Why Your Count May Differ

The American Dental Association states that people usually have 20 baby teeth, and all 32 permanent teeth¹ have usually come through by age 21. Baby teeth start to come in at about 6 months. The counts per jaw, and the 28 without wisdom teeth, follow from these totals by simple arithmetic.

Adult teeth come in four kinds, from front to back: incisors, the flat cutting teeth at the front; canines, the pointed teeth at the corners; premolars, the teeth between the canines and the molars; and molars, the broad grinding teeth at the back. The wisdom teeth are the last molars, one in each corner of the mouth, which is why there are four.

Children's teeth: 20 baby teeth, then the adult set

Most babies start teething at around 6 months, although some start before 4 months and some after 12 months. The NHS says most children have all their milk teeth by 2 to 3 years old². The baby teeth usually arrive in a rough order: the front teeth first, then the first molars, the canines, and the second molars last, with lower teeth often coming through before the matching upper ones.

From around school age, the baby teeth start to fall out and adult teeth take their place, while extra adult molars come through behind them. For some years a child has a mix of baby and adult teeth. The timing varies a lot from child to child, so there is no fixed "right" number for a given age. A dentist can tell you whether your child's teeth are coming through as expected.

Why you may have fewer than 32

Counting fewer than 32 teeth in the mirror is common, and usually not a problem. There are three main reasons.

Some teeth never formed

Wisdom teeth are the teeth most often missing from birth. A review of 92 studies with 63,314 people worldwide found that 22.6% had at least one wisdom tooth missing³, more than 1 in 5, although the figure varied widely between studies (from 5% to 56%). Missing one or two wisdom teeth was more common than missing three or four, and women were slightly more likely than men to lack one.

Other teeth can be missing too, a condition called hypodontia. Pooled studies found that about 6.4% of people were born without at least one tooth⁴ other than a wisdom tooth, with large differences between studies. The teeth most often missing were the lower second premolars, then the upper lateral incisors (the small teeth beside the two front teeth), then the upper second premolars. In most people with hypodontia only one or a few teeth are missing.

Some teeth have not come through

A tooth can form but stay under the gum or in the bone because there is not enough room or it is growing at an angle. This is called an impacted tooth, and wisdom teeth are the usual example. A tooth that is still fully under the gum cannot be counted in the mirror, and one that is only partly through can be hard to see; a dentist may use an X-ray to see where it is.

Some teeth have been removed

Teeth may have been taken out because of decay, gum disease, injury or for orthodontic treatment, or wisdom teeth may have been removed because they caused problems.

Do wisdom teeth have to come out?

Not necessarily, and the evidence points in more than one direction. The NHS says a healthy wisdom tooth will usually be left where it is and monitored⁵. UK guidance from NICE, published in 2000 and now being updated, states that the preventive removal of impacted wisdom teeth that are free of disease should be discontinued⁶, and that surgery should be limited to teeth with evidence of disease, such as decay that cannot be repaired, infection or a cyst. Having no symptoms is not the same as being free of disease, which is why a dentist's examination matters.

A Cochrane review found insufficient evidence⁷ to say whether impacted wisdom teeth with no symptoms and no disease should be removed or kept. It found that keeping them may be linked with gum disease around the neighbouring molar, on very low-certainty evidence, and suggested that people who keep them have them checked at regular intervals. A review of 37 studies concluded that kept wisdom teeth that cause no symptoms rarely remain disease-free over time⁸, most often because of decay or gum problems. One small trial in teenagers who had finished orthodontic treatment, at high risk of bias, found no clinically significant effect of removing wisdom teeth on the alignment of the other teeth.

Removal has its own risks. In a review of 44,171 extractions of impacted lower wisdom teeth, the nerve that gives feeling to the lower lip and chin was injured temporarily after 1.20% and permanently after 0.28%⁹ of them. The NHS says this kind of nerve damage usually gets better but can last a few weeks or months. Whether to remove or keep a wisdom tooth is a decision to make with your dentist.

Can you have more than 32 teeth?

Yes. Some people develop extra teeth, called supernumerary teeth. Whether one needs treatment depends on where it is and how it affects the teeth around it, which a dentist assesses.

When to see a dentist

The number of teeth matters less than whether they are healthy and working. Ask a dentist to look if:

• a baby tooth is still firmly in place well after the adult tooth should have replaced it, or an adult tooth has not come through
• a gap has appeared and the teeth around it seem to be moving
• a wisdom tooth area is painful or swollen, or the gum over it keeps getting sore
• you want to know whether you have teeth that have not come through: that needs an X-ray, chosen by the dentist after examining you

After a wisdom tooth is removed, get urgent dental help for bleeding that does not stop, pain or swelling that is severe or getting worse when painkillers are not helping, or pain with a bad taste in your mouth, a high temperature or feeling unwell. The NHS lists these as signs to act on⁵.

Emergencies. Swelling around a wisdom tooth, or anywhere in the mouth or face, that makes it hard to breathe, speak or swallow¹⁰ is an emergency: call 112 or go to the nearest emergency department.

Frequently asked questions