Short answer: A tooth chart is a map that shows the teeth in the mouth with two-digit numbers. In the FDI system, the first digit shows the quadrant (1 upper right, 2 upper left, 3 lower left, 4 lower right), and the second digit shows the tooth's position from the front middle toward the back. Permanent teeth are numbered 11-48 and baby teeth 51-85. For example, 36 is the lower left first molar, that is, the 6-year molar.
Seeing phrases like "cavity in 36" or "18 is impacted" in a dentist's exam notes can be confusing at first. These numbers are a standard address given to every tooth in the mouth. A tooth chart is a map that shows the place and type of the teeth in the jaw at a glance; tooth numbers are the language of that map. Below, in plain terms, we explain how many teeth there are in the mouth, the names of the teeth, and how to read the two-digit numbering system that is also widely used in Türkiye.
How many teeth are there in the mouth?
An adult has a total of 32 permanent teeth when the wisdom teeth are included. Of these teeth, 16 are in the upper jaw and 16 in the lower jaw. However, some of the wisdom teeth may never form, may stay impacted or may have been extracted; for this reason, adults with between 28 and 32 teeth in their mouth are quite common, and this by itself does not mean a problem.
The picture is different in children. When the baby tooth period is complete, there are a total of 20 baby teeth in the mouth: 10 in each jaw. Around age 6, the first permanent molars come in behind the baby teeth and the mixed dentition period begins. During this period both baby and permanent teeth are in the mouth at the same time; this is one of the periods when the tooth chart is most useful.
Tooth names: incisor, canine, premolar, molar
The teeth in the mouth are divided into four main groups according to their function and shape. The tooth names come from these groups, and in each half of a jaw they are lined up in the same order from the front middle toward the back.
- Incisors: There are two in each half of a jaw: the central incisor and the lateral incisor. They bite and cut food and are the teeth most visible in a smile.
- Canine: There is one in each half of a jaw. Thanks to its long, strong root, it helps tear food and acts as a guide in jaw movements. For problems with the position of the canine, you can take a look at our article on a canine that sits outside or high.
- Premolars: There are two in each half of a jaw. They act as a bridge between the incisors and the molars and begin to crush food. Baby teeth do not have premolars.
- Molars: There are three in each half of a jaw: the 6-year molar, the 12-year molar and the wisdom tooth. With their broad chewing surfaces, they do most of the grinding.
If we add up these four groups per half jaw, we get 2 incisors + 1 canine + 2 premolars + 3 molars = 8 teeth. Multiplied by four half jaws, this gives the number 32 in the permanent dentition. For more detailed explanations of the terms, you can use our dental glossary.
How is the tooth numbering system read?
The tooth numbers used in Türkiye and in many countries around the world are based on the two-digit system recommended by the FDI (World Dental Federation). In this system, each tooth is expressed with two digits, and it is read not as "thirty-six" but as "three-six."
- The first digit shows the quadrant (the region). The mouth is divided into four regions, and the numbering is done based on the patient's own right and left: 1 upper right, 2 upper left, 3 lower left, 4 lower right.
- The second digit shows the tooth's position. Counting starts from the central incisor at the front middle and goes toward the back: 1 central incisor, 2 lateral incisor, 3 canine, 4 first premolar, 5 second premolar, 6 first molar, 7 second molar, 8 wisdom tooth.
Once you know these two rules, you can easily decode any number. For example, 36 is the first molar in the lower left jaw, that is, the 6-year molar. 11 is the upper right central incisor, 43 is the lower right canine, and 28 is the upper left wisdom tooth. Because your right and left sides face the opposite way from the dentist looking at you, charts are usually drawn like a "mirror image"; for this reason, the right side appears on the left in the chart.
Other systems are also used in different countries. In the universal system common in the United States, the teeth are numbered with a single number from 1 to 32; in some orthodontic sources you may see the Palmer method, which shows the quadrants with bracket-like symbols. If a report from abroad uses a different numbering, your dentist can easily convert it to its FDI equivalent.
Tooth numbers chart for the upper and lower jaw
The breakdown below shows, quadrant by quadrant, which number corresponds to which tooth on the tooth chart. In each quadrant the order runs from the front middle toward the back.
Upper jaw
- Upper right (quadrant 1): 11 central incisor, 12 lateral incisor, 13 canine, 14 first premolar, 15 second premolar, 16 first molar, 17 second molar, 18 wisdom tooth.
- Upper left (quadrant 2): 21 central incisor, 22 lateral incisor, 23 canine, 24 first premolar, 25 second premolar, 26 first molar, 27 second molar, 28 wisdom tooth.
Lower jaw
- Lower left (quadrant 3): 31 central incisor, 32 lateral incisor, 33 canine, 34 first premolar, 35 second premolar, 36 first molar, 37 second molar, 38 wisdom tooth.
- Lower right (quadrant 4): 41 central incisor, 42 lateral incisor, 43 canine, 44 first premolar, 45 second premolar, 46 first molar, 47 second molar, 48 wisdom tooth.
If you look closely, the four numbers ending in 8 (18, 28, 38, 48) belong to the wisdom teeth. For when these teeth come in and their possible problems, our article on when wisdom teeth come in may help, and for the situations in which extraction comes into question, our article on wisdom tooth extraction can be a guide. The numbers ending in 6 (16, 26, 36, 46) are the 6-year molars.
Numbering of baby teeth
The same logic applies to baby teeth; only the quadrant digits change. The quadrants that are 1-4 in permanent teeth are used as 5-8 in baby teeth: 5 upper right, 6 upper left, 7 lower left, 8 lower right. Because there are five baby teeth in each quadrant, the second digit is between 1 and 5: 1 baby central incisor, 2 baby lateral incisor, 3 baby canine, 4 first baby molar, 5 second baby molar.
- Upper right (quadrant 5): 51, 52, 53, 54, 55
- Upper left (quadrant 6): 61, 62, 63, 64, 65
- Lower left (quadrant 7): 71, 72, 73, 74, 75
- Lower right (quadrant 8): 81, 82, 83, 84, 85
For example, 75 is the lower left second baby molar. Right behind this tooth, around age 6, the permanent molar numbered 36 comes in; families can often overlook this new tooth by assuming it is a baby tooth. The place of the baby molars is later taken by the permanent premolars (such as 14, 15, 24, 25). For the role of baby teeth in jaw development, you can read our article on why baby teeth matter, and for the eruption timeline of molars, our article on when molars come in.
Why do dentists use tooth numbers?
Dentists use tooth numbers because this system identifies each tooth with a single code, leaving no room for confusion. While a description such as "the back tooth at the lower right" can cover several teeth, "46" points to just one tooth. This precision matters especially in the following situations:
- Records and follow-up: Exam notes, treatment plans and check-up records can be easily tied to the same tooth even years later.
- Imaging: In panoramic X-ray or dental CT reports, findings are written with the tooth number; this way the information in the image matches the right tooth in the mouth.
- Communication between dentists: Dentists in different fields such as orthodontics, surgery, gum treatment or prosthetics speak the same language; the risk of misunderstanding in referrals and consultations is reduced.
- Orthodontic planning: In braces or clear aligner treatment, details such as how far which tooth will move and which tooth will get an attachment are planned with numbers.
If you are not sure which tooth a number corresponds to while reading your own treatment plan, do not hesitate to ask your dentist. The condition of a tooth, whatever its number, can only be assessed through an exam and, if needed, imaging; the chart only gives the address of that tooth.
Using the tooth chart in your own records
Knowing the tooth chart also makes it easier to keep track of your own oral health. If you note by number which tooth has a filling, which has had a root canal treatment or in which area you feel sensitivity, you can give your dentist clearer information at your next exam. Marking on the chart which of your child's baby teeth have fallen out and which permanent teeth have come in is also a practical way to follow the tooth-changing process.
If you have a question about the condition of your teeth, or would like to go through the numbers in a report together, at our clinic at Park Oran Ofis in Oran, Çankaya, we can go over your chart with you step by step during the exam. If deemed necessary, treatment options are planned by the dentist after the exam.
Frequently asked questions
Which tooth is number 36?
36 is the first molar on the left side of the lower jaw. It is commonly known as the 6-year molar. The first digit, 3, refers to the lower left region, and the second digit, 6, points to the sixth tooth counting from the front middle.
What are the numbers of the wisdom teeth?
In the FDI system, the wisdom teeth are shown with the numbers 18, 28, 38 and 48. They correspond to the upper right, upper left, lower left and lower right wisdom teeth respectively. These teeth may not form in everyone or may stay impacted.
Why do right and left appear reversed on a tooth chart?
The numbering is based on the patient's own right and left. Charts, however, are usually drawn from the angle at which the dentist looks at the patient, so the patient's right side sits on the left of the chart. For this reason, it is safer to rely on the numbers when reading the chart.
How many baby teeth are there and how are they numbered?
There are a total of 20 teeth in the baby dentition, 10 in each jaw. In the FDI system, the quadrant digits 5-8 are used for baby teeth, and the numbers are 51-55, 61-65, 71-75 and 81-85.
Is it a problem to have fewer than 32 teeth?
Not always. Because wisdom teeth may not form, may stay impacted or may have been extracted, many adults have between 28 and 32 teeth. The effect of missing teeth on oral health is evaluated at the exam.
