Teeth are the only part of the human skeleton that is not protected by mucous membranes, dermal tissue or muscles, so they are easily susceptible to negative factors and require increased and regular hygienic care. Compliance with oral hygiene standards depends not only on appearance and the structure of the teeth, but also their number.
An abundance of sweet and spicy foods in the diet, improper brushing, accumulation of food debris between the teeth, and crumbs getting into periodontal pockets - all this can lead to purulent infectious processes and tooth loss. If a person takes care of his teeth, regularly undergoes preventive examinations with a dentist and follows the principles healthy eating, the number of teeth he has must correspond to physiological norms.
Types of teeth in the oral cavity of an adult
During infancy, a person begins to erupt milk teeth, which after a few years are completely replaced by permanent ones. This process is long and can take from 6 to 9 years. The replacement of baby teeth is completed during puberty - by the age of 12-14 years. Girls usually develop permanent teeth a little earlier than boys. There are cases when the last molar appeared in the period from 9 to 11 years - this situation, in the absence of any pathological changes in the structure of the dental tissue, is considered a variant of the norm.
Molars are permanent teeth - a person will live with them for the rest of his life, so it is important to know the basics proper care take care of your teeth and gums and follow the recommendations of dentists to avoid tooth loss and the need for artificial crowns or dentures.
The dentition of an adult consists of frontal sharp incisors, canines, premolars and molars. Incisors are the most sharp teeth human jaw necessary for biting hard foods. To the side of them are the fangs, and the dentition is completed by the small and large ones. All teeth are always located in a strictly defined sequence, have their own number and perform certain functions.
| Name of teeth | Serial number (counted from the middle of the dentition) | Description | What function do they perform? |
|---|---|---|---|
| Incisors (front teeth) | 1, 2 | Front teeth located in the center of the dentition. The sharpest of all teeth found in the human mouth | Biting food |
| Fangs | 3 | They have a cone shape, located immediately after the second incisors | Tearing food |
| Small molars | 4, 5 | Molars coming after the canines. Most often have one or two roots | Grinding, chewing food, tearing soft pieces |
| Large molars | 6, 7, 8 | Molars that have tubercles for grinding food and fissures - depressions and small pits on the chewing surface of the tooth enamel | Chewing food |
Pay attention! Eights are the extreme molars, coming after the second large molars, which usually erupt between the ages of 17 and 30 years. For some people, figure eights () do not appear at all.
Video - Anatomy of teeth
Number of teeth in an adult
Third molars, which are “wisdom teeth,” do not appear in everyone, so the minimum number of teeth in an adult is considered to be 28 teeth: 8 incisors, 4 canines and 16 small and large molars. This amount can remain constant if a person does not erupt at least one wisdom tooth. The time and fact of eruption of the extreme molars is influenced by several factors, including:
- Climatic conditions in the place of residence. Residents of southern cities usually erupt all four third molars due to the high content of vitamin D in the body and the associated active absorption of calcium.
- Heredity. If parents have more than one wisdom tooth, the likelihood that their children will also develop them is very high. Genetic predisposition also affects the time of eruption, as well as the painfulness of the process.
- Features of the diet. In people who consume a lot raw vegetables and fruits, eights appear in 80% of cases due to constant contact with solid food.
Important! If “wisdom teeth” have not appeared by the age of 30-32, it is recommended to consult a dentist and have an x-ray taken. In some cases, the absence of third molar buds is a congenital pathology resulting from abnormal intrauterine development. An X-ray will allow you to assess the condition of the jaw and exclude other hidden anomalies in the formation of the maxillofacial part of the skeleton.
The location of the 32 teeth in an adult:
3 molars () upper and lower (left side) 1 and 2 top and bottom (left side) top and bottom (left side) Upper and lower lateral incisors (left side) Central upper and lower incisors Upper and lower lateral incisors (right side) Upper and lower canines (right side) 1st and 2nd premolars upper and lower (right side) 3 molars (wisdom teeth) upper and lower (right side) How do the trailing molars (figures of eight) erupt?
Third molars are the outermost molars that close the dentition, which are popularly called “wisdom teeth.” There are four of them in total - one at each end of the upper and lower dentition. In most cases, eights appear in pairs, less often they can appear one at a time. In very rare cases, simultaneous eruption of three or four eights at once can be observed. In such situations, a person often requires hospitalization in the maxillofacial surgical department, since the teeth in the vast majority of such clinical cases erupt incorrectly or incompletely.
Even if only one wisdom tooth emerges, a person may experience the following symptoms:
- swelling and swelling of the gums at the site of closure of the dentition;
- severe pain that is almost not relieved by analgesics;
- cracks and abrasions on the gums;
- bleeding at the site of eruption;
- intoxication of the body;
- headaches;
- severe weakness and decreased performance.
Important! If a person is showing signs of third molar eruption, they should consult a dentist. In case of a complicated course, the patient will be advised surgical treatment, consisting of deleting .
Video - Is it really necessary to remove wisdom teeth?
How many teeth should older people have?
In elderly people, it is no different from the physiological norms in other people, but here it is important to take into account the age factor. Tooth enamel wears and wears off over time, leading to increased tooth sensitivity and susceptibility to various infections. Based on the degree of wear on teeth and dental crowns, the dentist can determine the approximate age of the patient.
The first changes appear at the age of 20-25 years. There is no strong smoothness at this age yet, but if a person suffers from obesity, bulimia and other disorders in which heavy food consumption occurs, then even at this age the doctor may notice the first signs of bone covering on the chewing surface of the teeth - dentin. By the age of 45-50, dentin already covers most of the tooth, the crown wears out, and the tooth enamel becomes thinner. This leads to the fact that people over 60 years old have practically no teeth.
The number of teeth in an adult is not constant. It depends on the characteristics of intrauterine development bone tissue, oral care and other factors. Most adults, in the absence of carious teeth to be removed, have 29-30 teeth in their mouth. If the third molars never erupted, there will be 28 of them. If a person has lost all their wisdom teeth, the total number of teeth will be 32, but this occurs in about a third of people aged 18 to 50 years.
Video - About human teeth
From this article you will learn:
- How many teeth should a person normally have?
- in which cases there are fewer teeth,
- human dental formula - diagram, numbering of teeth.
Human teeth can be temporary or permanent. Temporary (baby) teeth normally begin to erupt in children from 8 months to 3 years of age, but in modern children, eruption may begin earlier. In total, a child should have 20 primary teeth erupting – that’s 10 teeth per upper jaw+ 10 teeth on the lower jaw.
From about 6 years of age, temporary teeth begin to gradually fall out, and permanent molars erupt in their place. Most permanent teeth erupt between 6 and 12 years of age, and only eruption ( last teeth on each side of the dentition) - usually occurs between 17-21 years. In total, an adult can erupt 32 teeth - 16 teeth each in the upper and lower jaws, but there are rarely exceptions.
The teeth of a child and an adult are x-rays –
Thus, how many teeth a person has depends on age. Normally, at the end of the eruption of all temporary teeth in children, there will be 20 of them. Then, from the age of 6, the period of replacing milk teeth with permanent teeth begins, when the child will simultaneously have both milk and permanent teeth in the oral cavity (this period is called the period of replacement teeth). bite). Once all permanent teeth have erupted, a person will normally have 32 permanent teeth. Read more about the timing of teething at the link below.
Numbering of teeth in dentistry: scheme for adults and children
The numbering of teeth in dentistry seems to be a very interesting point, because... a patient can often hear or read in a medical card that the doctor treated his 37th or 42nd tooth (although there are only 32 of them). The fact is that tooth numbers in dentistry do not correspond to simple ordinal numbers from 1 to 32 in adults, and from 1 to 20 in children.
What does the dental formula look like in a medical record?
The dental formula of an adult, as well as a child, in the medical record of a dental patient looks in the form of a schematic table (Fig. 5), which will reflect only the serial numbers of permanent or baby teeth. Directly in this formula, the doctor will mark the missing teeth (in this case, the number is crossed out with a cross), which teeth are affected by caries, pulpitis or periodontitis, as well as which of them have crowns or bridges.
Dental formula in the form of a table in the medical record –
What are the exceptions to the number of teeth?
There are situations when the number of teeth a person has differs from the norm. For example, the rudiments of some teeth may be completely absent, or they die during development. As a rule, this is a consequence of diseases either suffered by the mother during pregnancy, or diseases of the child in the first years of life.
There are situations when a child may experience delayed teething, and parents are worried about this. It should be noted that in modern children, early or late teething is observed in approximately 30-40% of cases from standard periods. This process is influenced not only by diseases of the mother and child, but even by the nature of nutrition during breastfeeding.
Important : have a great influence on the eruption of permanent teeth inflammatory diseases at the roots of baby teeth (the latter arise as a consequence of untreated caries). can lead not only to a delay in the eruption of a permanent tooth, but also to the death of the permanent tooth germ. In the latter case, there will be no permanent tooth in this place.
Supernumerary teeth
–
Sources:
1. Higher prof. The author's education in dentistry,
2.
National Library of Medicine (USA),
3. “Therapeutic dentistry: Textbook” (Borovsky E.),
4. "Children's room" therapeutic dentistry. National leadership" (Leontyev V.).
Human teeth, like those of other mammals, perform an important function. They can be used to bite and chew food. Their participation in the formation of speech and the pronunciation of sounds has been proven. Depending on what function they have, they have different shapes and location. They are formed from hard fabrics, they are durable and last for a long time. At the same time, they are easily affected by negative factors and need regular hygienic care. If a person has healthy teeth, this indicates his good health.
Geneticists and dentists have noticed that teeth have changed during the process of evolution. The first people ate solid and raw food. Their jaws were stronger, and all teeth were involved in chewing. Now the food is very different from what our ancestors ate, and the lower jaw modern man became much smaller. Now, not all molars have enough space, and often there is not enough room for them to erupt, and the number of teeth may vary in modern humans.
How many teeth does a person have?
During his life, a person manages to change one set. The very first breasts appear approximately four months after birth. These are baby teeth and by the age of three there are 20 of them. Starting from the age of six, the milky ones begin to fall out, and permanent ones erupt in their place.
In terms of their characteristics, milk pearls are very similar to indigenous ones. To the question: “How many baby teeth does a person have?” It has already been said that 20. But there are still several differences between them: size, quantity and color. The pearls are located more vertically, and their roots are shorter.
Girls develop molars faster than boys and by the age of 13 they already have 28 teeth. Two more on each jaw grow by the age of thirty. In total, the complete dentition includes:
- 4 fangs
- 8 incisors
- 8 small molars
- 12 major molars
It turns out that Humans have 32 teeth in total.. Should everyone cut through? The third molars, which are the same ones, in the amount of 4 pieces, are the very last to erupt and not for everyone. People with an incomplete set of recent years more and more, and they may not worry about the changes in evolution that affected them. The main thing is to be healthy and it doesn’t matter whether there are 28 of them or 32.
Structure and types
You need to know how many teeth an adult has, as well as the structure of milk and permanent teeth.
Main parts and structure of teeth:
- Root.
- Neck.
- Crown.
- Gum.
- Tooth enamel.
- Dentin is tooth bone.
- Dental pulp.
- Dental cement and periosteum.
- Olveolus is a dental cell.
Root- this is the part of the tooth that is located in the dental cell. It can have from one to three roots and is cone-shaped. The covering that contains the root is made of bone-like cement. They are interconnected by numerous fibers, with the help of which the tooth is held in place, but at the same time maintains the desired mobility. This “glue” reduces the likelihood of injury while chewing food. Incisors and canines each have one root, while molars have 2 or 3 roots.
Inside there is a small cavity that goes into the root with a canal, at the top of which there is a hole. It's filled inside pulp. The pulp contains nerves and blood vessels. They just pass through a tiny hole in the root. Main function The root is that it needs to fasten the tooth to the jaw with the help of a ligamentous apparatus.
Crown- this is the important part. It is located above the gum and covered with enamel. IN correct position it should recede slightly from the gums. There is a cavity in it that flows into the dental canal, and in the cavity there is pulp. The pulp fills not only the crown part, but also the root part.
Neck- this is the narrowed part in the place where it comes into contact with the gum. It is located under the gum, or rather, under its edge and passes into the root cement, and begins where the enamel ends.
Enamel- this is the main protection; the condition and health of the tooth depends on its quality. Like nerve cells, tooth enamel is not restored. Its strength can decrease from damage and neglect, and it can also be:
Under the influence of negative factors, the enamel is destroyed, the surface is erased, and it can only be restored artificially in the dentist’s office.
Dentine- it is a dense, hard fabric, yellow color, forming the main mass of the tooth. It defines its shape and has high elasticity. Dentin is formed even before eruption and affects the future size.
When wisdom teeth erupt, you may experience the following symptoms:
- severe pain that is difficult to relieve even with painkillers;
- abrasions and cracks on the gums;
- edema, inflammation or swelling at the end of the closing dentition;
- headache;
- bleeding;
- decreased performance and lethargy;
- general intoxication of the body.
Wisdom teeth take part in chewing and grinding food, and with proper growth and position, they increase chewing efficiency. Extraction of third molars in such cases is a common practice throughout the world.
When do adults begin to lose teeth?
The older a person is, the fewer teeth he has. But all this depends on factors such as poor oral hygiene, bad habits, in particular, cigarette smoking and heredity. Some people no longer have one at the age of 19, while others still have everything at 35. In old age, many already have false teeth or 10-20 pieces. The enamel and crown wear out completely, and after 70 years only the neck and roots remain.
How to keep your teeth healthy
To keep them healthy you need to take care of them from the moment they appear. Not everyone knows how to properly monitor them in order to maintain their number and health for as long as possible. Here are some recommendations that will tell you how to properly care for them:
If you follow these simple rules and visit the dentist in a timely manner, you can prolong the youth of your teeth and enjoy your favorite dishes longer. In addition, the number of teeth a person has directly depends on the care they take.
When asked how many teeth an adult should have, everyone will answer without delay: According to the norm, 32 teeth. But if you take the topic seriously and count the number of teeth on the upper and lower jaw, you may be surprised, since there will be fewer than the expected number. Let's try to find out why this happens, which cases can be considered normal, and which require medical intervention.
Features of the growth of baby teeth
Babies are completely missing teeth. Sometimes there have been cases of children being born with a pair of milk elements, but this circumstance is an exception. Pediatricians say that teething should begin at about 7–8 months of a baby’s life, but there are often situations when parents notice the appearance of the first incisors already at 4–5 months.
All baby teeth grow in before the age of three, but often this general date shifts by six months in one direction or another. According to dental experts, this development of events is normal.
Teething order
The chronology of the formation of milk teeth in infants is as follows:
- The incisors are the first to erupt into the oral cavity. By 8–9 months their number should be 4: two on top and two on bottom.
- By the time a baby reaches one year, the jaw row should number eight to ten teeth, but sometimes there are twelve of them, which is again normal. At this time, the lateral incisors grow.
- By the age of two, a little person has eighteen to twenty elements in his mouth. By 18 months the first molars appear, by 24 months the canines appear, and then the second molars. Thus, by the age of 2, a person has 8 incisors and molars, as well as 4 canines.
- After two years and 6 months, the so-called resting period begins, when tooth growth slows down. But for a small person, the twenty that is available is enough to chew food. At this age, an important task for parents becomes hygienic education of children, explaining the need for cleanliness and oral health.
How many permanent teeth do adults have?
According to the norm, an adult person should have 32 teeth: 16 on top and bottom respectively. The dental composition on the upper and lower jaws is the same; only the shape of its individual elements may differ slightly.
Incisors
The number of permanent incisors in an adult is equal to the number of baby teeth of the same name in children: 4 on each jaw. They can be central or lateral. In the top row large sizes have central elements, and on the bottom - side ones. This formation allows them to optimally perform the function of biting, “cutting” pieces of food.
Fangs
Both babies and mature people have 4 such teeth: 2 on top and 2 on bottom. The shape of the fangs is in many ways similar to that of carnivores.
Molars
They perform the function of chewing and grinding food, and can be of two types:
- Premolars or small molars. The number of such teeth in an adult is usually eight: 2 pairs on each jaw. They are located between the fangs and molars. One premolar has a rounded shape and is placed at an angle towards the tongue. The second premolar is larger than its counterpart, covered on top with pronounced tubercles.
- Large molars or molars. An adult person has 12 such teeth, they differ by type. The first molars are large, rectangular in shape, have pronounced cusps and two roots, each of which contains one dental canal.
The second and third molars are similar to the first, with some differences only in the shape of the fissures and cusps.
Adults usually have four wisdom teeth—third molars—but sometimes there may be fewer of them, or they may not grow at all. If there are no wisdom teeth in a person, there are 28 positions in the mouth. For what reasons this happens, read below.
Why don't all people have wisdom teeth?
It is not for nothing that wisdom teeth received such a name, since they appear in adults - from 18 to 25-26 years. These teeth often do not grow in full numbers, for example, one on each jaw, or do not erupt at all. If the growth of the third molars proceeded without complications, the discomfort went away after complete eruption, then any number of them will be a variant of the norm.
Conclusion: 32 permanent teeth in humans is the standard norm, along with “wise” teeth. But many people grow only 28 permanent teeth, and dentists also consider this to be normal, saying that during the course of evolution, “wise” elements may disappear altogether.
In rare cases, on the contrary, a person has 33 teeth, the fifth “sage” erupts in the front of the row. This phenomenon entails discomfort and spoiled aesthetics of the jaw, so the excess element must be removed.
According to experts, an additional third molar is a deviation from the norm, which is formed during intrauterine formation. For example, if the pregnancy was multiple and one of the embryos died, passing on an “extra” tooth to a brother or sister.
Modern dentistry helps to easily cope with any dental ailments. But, as before, the main condition for dental health is daily brushing twice a day, visiting the dentist at least once every six months and timely treatment of dental diseases.
The basis of the human skeleton is the bone apparatus. Almost all bones are protected soft tissues. Precisely “almost”, since the exception is teeth. They are not covered with muscles, mucous membrane, or skin.
Fortunately for humans, teeth change only once during life. But this does not make it any less significant. In particular, the number of teeth will depend on compliance with hygiene standards. mature age, their internal safety and appearance.
There are differing opinions about how many teeth a person should have healthy person, carefully monitoring their health and, in particular, oral hygiene.
Everyone knows: “32 teeth is the norm!” What to do with the so-called? Are they included in this number? Or is this a nice addition to this kit?
How many teeth a healthy mouth should have depends not only on age, but also on individual physiological characteristics.
The third molars, located in front of the “figure eight”, have up to 5 roots, which can be tightly woven into a single, denser, stronger one. But wisdom teeth have up to 8 roots at once. This is explained by its location close to the pulp. The canals of such teeth can bifurcate, and sometimes several canals are found in one root. For this reason, when removing wisdom teeth, it is necessary to take a photo.
Only in this way will the doctor be able to determine the number of roots and canals of the molar.
Age characteristics
Teeth change throughout life. If in children they are weakly fixed, then in adults completely different processes are observed.
With age, teeth wear out, and an experienced dentist can quite accurately determine the patient’s age based on the degree of wear. Also, wear and tear depends on the texture of the food eaten and physiological characteristics.
Up to the age of 16, no signs of erasure are visible. But by the age of 20, a slight smoothness appears on the teeth, which is quite natural for 
this age.
Over the next ten years, the tubercles and sharp cutting edges are overgrown with a dentin coating - bone substance. At the age of 45, serious wear of the crown protrusions is already visible, and dentin appears in significant areas.
At the age of 60, both the tooth enamel and the crown are completely worn out. After 70 years, only the neck and roots remain. Although by this time most of the teeth fall out or are pulled out due to caries.
To summarize, a healthy person should have at least 28 teeth, this is already considered the norm. Depending on a number of nuances, by the age of 30, fourth molars may also erupt, thereby bringing their number to 32.