Teeth Names

Teeth Names in Order: Front to Back

In short, the teeth names follow the job each tooth does. At the front sit the incisors, flanked by the pointed canines. Behind them come the premolars, then the molars, with wisdom teeth last in line. Both sides mirror each other, so the left half of your mouth matches the right.

Teeth names in one quarter of the mouth

Count backwards from the gap between your front teeth. First come the central and lateral incisors. Next you reach the canine, then the first and second premolars. After that sit the first, second and third molars, eight teeth in all. Every quarter repeats this pattern, which is why teeth names always come with a position.

Why Do Some Adults Have 28 Teeth and Others 32?

A complete adult set has 32 teeth. That means eight incisors, four canines, eight premolars and twelve molars. Four of those molars, however, are wisdom teeth. Yet some people never develop all four, and others have them removed. So a healthy adult can have anywhere from 28 to 32 teeth.

This table lines up the teeth names with their numbers, positions and everyday jobs.

How common are missing wisdom teeth?

Agenesis means a tooth never forms. One large meta-analysis measured how often this affects wisdom teeth.

“The worldwide rate of agenesis was found to be 22.63% (95% confidence interval = 20.64% to 24.76%).”

Carter and Worthington, meta-analysis of 92 studies, Journal of Dental Research (2015)

The NHS says wisdom teeth usually come through in the late teens or early twenties. If one lacks room, it may stay impacted; our wisdom tooth extraction page explains when removal helps. Further forward, a single tooth implant or bridge can replace a lost molar.

Incisors and Canines: Which Teeth Show When You Smile?

Your smile mainly shows incisors and canines. First, the front of each jaw holds four incisors, two central and two lateral. A canine stands at each corner, with a long root and a pointed tip. Of all the teeth names, these are the easiest to spot because their shapes differ.

Incisors: built for biting

These front teeth have thin, sharp edges that slice into food. They also support the lips and help you pronounce “f” and “v”.

Canines: the cornerstones of the bite

Canines have some of the longest roots in the mouth and anchor each corner. When your jaw slides sideways, they often guide the movement and protect the back teeth. For example, an impacted canine frequently becomes part of a braces plan.

Premolars and Molars: Which Teeth Do the Chewing?

Behind each canine sit two premolars, which Americans often call bicuspids. Further back are the molars, the widest teeth in your mouth. Premolars usually have two cusps, while molars have four or five. Molars do most of the grinding, so these teeth names come up often at check-ups.

Premolars: the middle step

These teeth break food down before the molars finish the job. Most have one root, but the upper first premolar often has two.

Molars and the six-year molar

The first permanent molar arrives around age six, behind the baby teeth. As a result, parents sometimes mistake it for a baby tooth. Yet it has to last a lifetime and carries much of the chewing load. Its deep grooves trap food easily, so dentists often recommend a protective sealant.

How many roots do molars have?

Upper molars usually have three roots and lower molars two. That pattern helps a dentist plan root canal treatment, although numbers vary. An X-ray gives the final answer.

How Do Teeth Names Turn into Chart Numbers?

Most of the world uses the two-digit system from the FDI World Dental Federation. It also forms the basis of the ISO 3950 standard. The first digit names the quarter of the mouth. Then the second digit counts back from the midline. Tooth 36, for example, is the lower left first molar.

Quadrants 1 to 4, and 5 to 8 for baby teeth

Seen from the patient’s side, upper right is quarter 1 and upper left is 2. Lower left is 3 and lower right is 4. Baby teeth use 5 to 8 in the same order. So 55 is the upper right second baby molar. Every wisdom tooth ends in 8: 18, 28, 38 and 48.

To match a chart number with teeth names, work through these steps:

1. First, read the opening digit: 1–4 means an adult tooth, 5–8 a baby tooth.
2. Next, picture the quarter from the patient’s point of view, not the dentist’s.
3. Count back from the midline using the second digit.
4. Then match the result: 1–2 incisors, 3 canine, 4–5 premolars, 6–8 molars.
5. Finally, check any letter after it, such as M or D; it marks a tooth surface.

Universal and Palmer notation

The US Universal system counts adult teeth from 1 to 32, starting at the upper right wisdom tooth. So FDI 36 becomes Universal 19. UK records may use Palmer notation, where a bracket marks the quarter. Whatever the system, the teeth names stay the same.

Enamel to Pulp: What Every Tooth Shares

Whatever its name, every tooth shares the same layers. First, hard enamel covers the crown, with dentine underneath. Then, at the centre, the pulp holds nerves and blood vessels. So while teeth names change along the arch, the inner design stays the same.

Enamel

The hardest tissue in the body, covering the crown; once lost, it cannot grow back.

Dentine

The yellowish layer under the enamel, full of tiny tubules; sensitivity often starts here when enamel wears thin.

Pulp

The soft core of nerves and blood vessels; if it becomes inflamed, root canal treatment may be needed.

Cementum

A thin layer on the root surface that anchors the fibres holding the tooth in its socket.

Quadrant

One quarter of the mouth; the first digit of an FDI number tells you which one.

Crown, neck and root

You can see the crown, while the root sits below the gum. The narrow zone where they meet forms the neck of the tooth. Over-vigorous brushing can wear this area, so a soft brush and gentle pressure matter. Our guide to worn teeth covers the causes and the fixes.

Baby Teeth Names and the Switch to Adult Teeth

Children have 20 baby teeth: four incisors, two canines and four molars per jaw. So there are no premolars and no wisdom teeth at this stage. Baby teeth are smaller and whiter, with shorter roots. After age six or so they start to fall out. The last ones usually go by about age 12.

Numbers for baby teeth

Baby teeth keep the adult tooth names with “baby” in front. Their FDI numbers run from 51 to 85. After early loss, a space maintainer can stop neighbouring teeth drifting.