How many teeth should a person have? Teeth are essential. They help people talk, chew, and swallow food. Adults typically have 32, four of which are wisdom teeth.
One 2019 articleTrusted Source states that a full set of adults consists of 16 lower and 16 uppers.
In this article, we will discuss the anatomy and function, how many adults and children have, how to maintain healthily, and when to see a dentist.
How many teeth do adults have?
According to a 2019 articleTrusted Source, a full set of adults typically numbers 32, including four wisdom teeth.
Each row includes:
- four incisors, in the middle of the row at the front of the mouth
- two canine, one on either side of the incisors
- two premolars and three molars at the back, with five on each side
However, not everyone has third molars, or wisdom, in their jaw. If an adult has wisdom, they tend to start to emerge when a person is around 18 years old. They may not emerge at all.
If a wisdom tooth does not emerge properly or becomes infected, a dentist may have to remove it.
Anatomy of teeth
A primary study in OdontologyTrusted Source confirms that are made of calcium.
Teeth start to develop before birth, and children tend to have all their babies by the age of 3.
Each tooth consists of a crown and root.
The crown is the visible white part, and the root is the invisible part of the tooth hidden by the gums. The root anchors the tooth into the jawbone.
Teeth also consist of layers called enamel, dentin, cementum, and dental pulp.
Enamel
Enamel covers the crown or the outside of the tooth and protects it from physical and chemical injuries.
According to a 2020 article on tooth development in American Physiological ReviewsTrusted Source, enamel develops in three stages:
Secretory stage
Ameloblasts, which are a type of cell that only occur in the, make enamel.
Initially, these cells make enamel proteins and crystals. These proteins and crystals will eventually turn into the enamel.
Transitional stage
During this stage, around 25% of ameloblast cells die. Researchers believe this may be because they begin to contain too much calcium.
As a result, the ameloblasts produce fewer enamel proteins.
Maturation stage
During the maturation stage, enamel crystals grow, which makes the enamel hard and durable.
Ameloblasts also change their appearance, turning into either ruffle-ended or smooth-ended cells.
These different shapes stop the movement of small molecules in the enamel, helping to protect the crown of the teeth.
Dentin
Forms are the main trusted source part of dental tissues.
Dentin is a similar structure to bone. The cells that form dentin are odontoblast cells, similar to osteoblast cells in bone. Unlike bones, dentin does not have blood vessels.
Cementum
Cementum is a tissue that covers the root’s surfaces.
There are different types of cementum. According to a 2016 article in the journal, Japanese Dental Science ReviewTrusted Source, acellular fiber cementum covers between 60–90% of single-root and 33–50% of multi-root.
Other types of cementum, such as cellular mixed stratified cementum (CMSC), cover other parts of the roots. CMSC covers roughly 66% of molar roots.
The cementum’s primary function is to support and fix the teeth in the jawbones.
Dental pulp
The center of the tooth contains dental pulp, which consists of loose tissues, including nerves, blood vessels, and connective tissues.
If any bacteria get past the enamel and dentin, the pulp becomes inflamed in an attempt to protect the trusted Source of the tooth. Inflammation of the pulp can cause pulpitis, which can be very painful.
The dental pulp attacks the bacteria with antibacterial, immune, and inflammatory responses. This may cause the body to reject and fight off the bacterial infection.
However, if this does not happen, the dental pulp may remain inflamed. This causes part of the pulp to die and can cause a root canal infection.
What is the function of each type of tooth?
While teeth help people talk, their primary trusted Source function is to chew.
The teeth cut and grind food into little chunks, which allows a person to swallow and digest it easily.
However, different kinds of teeth have different functions.
A person can learn more about teeth names, types, and functions here.
There are four types of teeth:
Incisors
The incisors are what some people call the ‘front teeth.’
Adults typically have eight of these, with four along the top row and four along the bottom row.
Incisors cut food up into smaller pieces, which the teeth and tongue then move to the back of the mouth.
Canines
The canine is the one that is slightly more pointed than the others. Some people may call these ‘fang teeth.’
As well as cutting up and tearing food, these make sure that the upper and lower rows do not clash.
The shape of the canines allows them to guide the rows so that they smoothly slide off each other when the jaw moves.
Premolars
Most adults have eight premolars.
These are the larger ones that sit behind the canines. Humans have four along the top gums, and four along the bottom, two on each side.
The primary function of premolars is to begin grinding up the food.
Molars
There are three types of molars:
- first molars
- second molars
- third molars, or wisdom
These sit toward the back of the mouth, and most adults typically have eight molars, with a first and second molar on each side of the mouth.
Third molars, or wisdom teeth, sit right at the back of the mouth. Some people do not develop wisdom teeth.
The function of the molars is to grind up the food into smaller pieces to help people swallow easily.
However, wisdom does not typically have a function.
If adults have their wisdom teeth, they will have 12 molars.
How many teeth do children have?
The first set of teeth, or baby teeth, begin to emerge from trusted Sources when an infant is about 5 months old, and they will typically have their first full set by the age of 3.
A full set of baby teeth consists of 20 teeth. Each row of 10 includes:
- four incisors
- two canines
- four molars
Baby teeth do not include premolars. When a child reaches about 6 years old, their baby teeth will start to fall out, and adult teeth will replace them.
How to take care of your teeth
To help maintain a healthy mouth, the best way to take care of teeth is by brushing and flossing regularly.
The American Dental Association and the American College of Prosthodontists recommend:
- placing the toothbrush at a 45-degree angle so that it touches the gums and teeth
- paying particular attention to the gums and the molars
- brushing for at least 2 minutes
When flossing:
- use 16–18 inches of floss and wrap it around the fingers
- gently thread the floss between the teeth until it meets the gums and move it up and down
- use a clean section of floss every two teeth
When people first start to floss, they may notice that their gums bleed.
This is not uncommon and should stop when the gums become healthy after regular cleaning and flossing.
If the bleeding continues, see a dentist.
When to see a dentist
People should make regular appointments with a dentist.
A dentist will decide how often a person needs a check-up, according to their oral health.
A person should see a dentist if they experience any unusual symptoms, such as ulcers, infection, inflammation, or bleeding.
Some oral health problems that need a dentist’s attention are:
- tooth decay
- gum disease
- tooth loss
- oral cancer
Summary
Teeth are essential, as they help people chew, swallow, and talk.
Each tooth contains several structures that maintain oral health.
People must brush and floss regularly to keep their teeth and mouth healthy.