How Many Teeth Do Adults Have?

Having More or Fewer Than 32 Adult Teeth

It is possible to have more or fewer than 32 adult teeth.

According to the National Institute of Dental and Craniofacial Research, adults between ages 20 and 64 have an average of 25.5 remaining teeth due to tooth loss. Further, about 2.2% of these adults have no remaining teeth. Causes of tooth loss include trauma or injury to the teeth, gum disease, tooth decay, poor dental hygiene, lack of professional dental care, and smoking.

“Hyperdontia” is the medical term for having extra teeth, which are called supernumerary teeth. They can grow anywhere in the curved areas where teeth attach to your jaw. Extra teeth may grow on one or both sides of the mouth. You may have one extra tooth or several.

Hyperdontia typically doesn’t require treatment. But a dentist may recommend pulling any extra teeth if they interfere with your oral health.

Having fewer than 32 teeth, or hypodontiarefers to a condition where someone is born with missing teeth. In this case, one to six of the teeth never develop. The condition is hereditary and can be passed down from parent to child. Treatments include bridges, dentures, and dental implants.

Oligodontia is the congenital (present at birth) absence of six or more teeth. The teeth most often missing are the premolars, incisors, or third molars (wisdom teeth). Teeth can be undersized or narrowly shaped.

With oligodontia, primary teeth are sometimes retained while permanent teeth are coming in. Treatment for oligodontia may include bone grafting, braces, bridges, partial dentures, dental implants, and reshaping of teeth.

Children Have Fewer Teeth

Children have just 20 teeth called primary, temporary, or milk teeth. They have 10 on each jaw. These include four incisors, two canines, and four molars.

The primary teeth start to erupt through the gums when a baby is about 6 months old. The lower incisors are the first primary teeth to come through, and most children will have all 20 primary teeth by the time they are 3 years old.

Children will lose their primary teeth between ages 6 and 12. Those teeth are replaced by permanent teeth, with the molars being the first permanent teeth to come in.

Summary

You have two complete sets of teeth over your lifetime. Your teeth are essential for biting and grinding up food.

A complete set includes 16 teeth on your bottom jaw and 16 on your upper jaw. Of those, you have eight incisors, four canine teeth, eight premolars, and eight or 12 molars.

Four of your molars are your wisdom teeth, which may come in your teen years or as late as your early 20s. It is also possible for wisdom to not ever develop, which is common and does not cause problems.

It is possible to have less than due to tooth loss and conditions that lead to more or fewer teeth. Children tend to have fewer teeth than adults.

If you take care of your teeth, they can last your entire life. To keep teeth in good shape and avoid tooth loss, brush and floss regularly and follow up with your dentist for dental cleanings and screenings every six months. It is also a good idea to protect your teeth from injury and not smoke.