How many canals are there in the front tooth? Root canal types

In total, a person has thirty-two teeth - sixteen in each jaw. They differ in shape and function: there are incisors, canines, small molars and large molars. Before we tell you how many roots a molar has, let's find out more about the teeth.

Tooth structure

Each tooth in the mouth has a crown protruding above the gum, an enclosed gum neck and a root, which is located deep in the tooth socket. Almost all teeth have only one root, and only a few have two or three roots. The tooth is formed by dentin. In the area of ​​the crown of the tooth, the dentin is covered with enamel, and where the neck and root are located - with cement. Inside the tooth there is a cavity made up of a crown cavity, which passes into a narrow root canal, which opens with a hole at the apex. It is through it that the nerves and blood vessels pass into the cavity of the tooth containing the pulp. Around the root there is a connective tissue periodontium, which plays the role of a tooth retainer in the dental alveolus.

Teeth growth

During his life, a person experiences two periods of teething. When a newborn is born, he has no teeth. They begin to erupt in the period from six months from the age to two years and thus twenty milk teeth, that is, ten on each jaw. Then the second period begins, lasting from six to twenty, and in some even up to thirty years, when thirty-two permanent teeth grow. The last, later than all, teeth that appear - the so-called wisdom teeth, may not appear at all, or they do not erupt completely. This is usually directly related to the individual characteristics of the individual.

Function of teeth

The functions of the teeth directly depend on their structure. So, the incisors have a crown similar to a chisel and these teeth are located in front of four on the upper and lower jaws. The canines differ in length and they sit long and deep. These two types of teeth have simple single roots, and they themselves serve to bite off food. Behind the canines are two small and three large molars, and they are located on each side of both jaws.

Permanent teeth

Finally, we got to finding out the specific question, how many roots the molar has and it turns out that it can be different amount... So, the small molars have a single root, and the large molars of the upper jaw have three roots, and their counterparts on the lower jaw have two. These teeth have a bumpy chewing surface, and they are designed to crush and grind food.

As already mentioned, the upper large molars have three roots - two buccal and one lingual, while the lower ones have two roots of which one is anterior and the other is posterior. Wisdom teeth have three roots, which can merge into one, which has a conical shape.

We protect teeth

If the teeth are not in order, then the person's digestion is disturbed, due to the ingress of poorly chopped food into the stomach, as well as its insufficient preparation for further chemical processing. In addition, microorganisms get inside, which can provoke inflammatory processes in the intestines or in other important organs. All this suggests that your teeth need daily careful care. They should be cleaned twice a day - in the morning and in the evening, after meals, and in general after each meal, they must be thoroughly rinsed. oral cavity.

By themselves organs that are not regenerated. Therefore, they must be protected. Healthy teeth are a guarantee of a person's well-being. This is easy to explain. A person receives vital energy from food. They are the first in the long chain of digestion of consumed food. The amount of minerals and useful elements that the body receives during processing depends on their quality of work.

Proper hygiene and dentist help keep your teeth healthy. You must visit it at least every six months. He will detect the disease at an early stage and cure it. If examinations are not carried out regularly, then this threatens with serious ailments. And they require long-term treatment. This pattern is associated with structural features. Although it looks lifeless, it actually feeds like any other organ.

How the human tooth works

For all their seeming fundamentality, these organs are exposed different diseases... This happens with poor care and bad habits.

In dentistry, rows are divided into the following types of teeth:

• incisors (central and lateral);
• fangs;
• premolars (small molars);
• molars.

The development of rows begins at the stage of bearing a child. It is during this period that the rudiments of some permanent teeth are formed. After birth, in a six-month period, the eruption of milk begins, which are gradually replaced by permanent ones. In adolescence from 10 to 13 years. The last 4 (third molars or eights) during this period are just beginning their development, so their appearance is delayed. They are born from 16 to 25 years old. As a result, the total figure for the number of teeth in a person is 32.

Each performs its own task, so they have a certain structure. They correspond to the opposite. But it is worth noting that the anatomy of the teeth of the upper jaw is different from the lower one. And this is not only a matter of the external difference. Significant changes are visible in the root system. They will be strong in teeth that are experiencing increased stress - upper and lower molars.

The anatomical structure of any one consists of three main parts:

1. crown;
2. neck;
3. root.

Dentists divide the visible area into four surfaces:

• closure (place of contact with the opposite row);
• lingual (inner side);
• front (outer side);
• docking with adjacent teeth).

The crown is covered with enamel, underneath is a layer of dentin. Together they form the basis of the crown. Dentin is similar in structure to bone tissue, but stronger. This is explained by increased mineralization. slightly different in its structure, since there is no enamel layer on it, and the dentin layer is penetrated by collagen fibers.

In the middle of the crown is the pulp, which is penetrated by blood vessels and nerve endings. The defeat of enamel by caries with untimely treatment leads to damage to the dentin and pulp, which causes severe pain.

The alveolus is not visible part- root. It is a natural extension of the jawbone. The number of roots of the teeth is different for each of the row. He alone is at the incisors, canines and the premolar of the lower jaw. The hidden part of the pairs of molars is different. So on the lower jaw, they have two roots, and on the upper jaw, they have three. The hidden part can also be customized. The roots of the wisdom tooth are from three to five.

The number of canals in a tooth does not always correspond to the roots. Their development depends on the load on them. And deviations from the norm are not pathology in dentistry. If it bifurcates at a papule, then it will not be difficult for the dentist to find it and fill it. Treatment if this is observed at the root. You won't be able to see this without an X-ray and modern dental equipment.

Number of tooth canals

Dentistry operates with the percentage of the number of canals. But this is not the norm, and the inconsistency with these data does not indicate an anomaly in the development of the jaw system.

It has already been mentioned that the root system of all teeth of the upper row differs from those of the lower one. These differences are sometimes significant. Therefore, the location of the canals is often a mystery for the dentist. An x-ray helps to clarify the situation.

1. The central incisor has two canals. But such cases are few. Most are single-channel cutters. The brother from the upper jaw is always single-channel. The second cutter from the bottom has 2 channels.
2. The canines or eye teeth located in the lower row are two-canal. Only 6% have one. Canine upper jaw 100% with one canal.
3. The first premolars have approximately the same percentage location. Dental canals are more often found here in two. But there are situations when there are only one or three of them. This often happens with top fours.
4. Second premolars are rarely three-channel. The percentage of such cases fluctuates within one. About a quarter of the population has two channels. The rest have one. Five on the bottom row at 89% with one channel, the rest with two.
5. The six on the upper jaw in 57% of cases is attributed to three canals, four in 4%. The same tooth is on the bottom row: two in 6%, three in 65% and four in 29%.
6. Seven (upper jaw) at 70% with three canals and four at 30%, the lower row - two canals at 13% and three at 77%.
7. Unpredictable canal anatomy is often found in eights. There are from two to five of them in the top row. In the lower one there are usually three of them. They rarely have the correct shape and are difficult to treat. As a rule, dentists with a damaged wisdom tooth recommend their removal.

Such are the placement percentages. The canals in the teeth are curved, or narrow, making treatment difficult.

Possible root canal diseases and their treatment

It is needed for nerve inflammation (pulpitis). In case of pathological processes in the soft tissues of the periodontium (periodontitis), the same procedure is prescribed. many. These are their endings, which penetrate the pulp and canals along with the blood vessels. That is why when a person is affected by caries, a person feels unbearable pain.

Treatment for periodontitis and pulpitis. This procedure is necessary if the listed diseases have chronic form... Root canals are treated by cleaning them from their contents and sealing them tightly.

Dental clinics today use cofferdoms (rubber pads) for these procedures. The treatment is safe and sterile. Since the rubber dam isolates. Go through the whole procedure in several stages.

1. Diagnostics is being carried out. At this stage, an X-ray or computer study of the invisible parts of the crown is prescribed. This helps to establish the number of roots and canals of the tooth. If this is not done, then the possibility that not all channels will be cured remains. Since the actions of the dentist in this case are carried out blindly. In the future, you will need retreatment of the tooth canals.
2. The dentist, having visually determined the location and number of canals, gets to them with various instruments. This usually occurs through the carious cavity and the removed apex of the pulp chamber with the removal of the tooth nerves. Before starting the procedure, the patient is injected with a local anesthetic. There are as many nerves in a molar as there are roots. They provide him with food. But even after removing the nerves, it serves for a long time.
3. After that, the canals of the tooth are filled, cleaning them and filling them with material. Cleaning involves mechanical and chemical action. The first is done with tools that scrape the content. And dry cleaning involves the treatment of moves with preparations that have a disinfectant effect. They are injected using a fine needle. The final stage is an airtight seal. This strengthens the tooth and protects against the penetration of pathogenic bacteria.

It is important to cover the entire length when cleaning the canals. Therefore, at the end of the filling, another control image is assigned. He will confirm the correctness of the procedure. filling material. Only then can the treatment be considered successful.

If the dentist is not sure about the treatment, he will place a temporary filling on the tooth. Pain with inflammation of the pulp is felt 14 days after treatment. But her character should not be growing.

If the procedure is successful, the inflammation will calm down and after two weeks the dentist will place a permanent filling. It is important that the doctor treats all channels at one time. This will protect against further inflammation. Therefore, it is important to know the number of canals in the teeth before starting the procedure.

Canal filling will be refused if the image shows its abnormal curvature. It simply cannot be done. Sclerosed canals are also a reason for refusing treatment. It all depends on the professionalism of the attending physician and in his technical capabilities to perform this or that procedure.

The root canal system in the tooth is a kind of tunnel through which nutrients and nerves pass. The space of the canals is filled with pulp tissue, which consists of a collagen complex with lymphatic and blood vessels, nerve fibers. With the development of a carious process with damage to hard tissues up to the pulp chamber, conditions are created for the rapid spread of infection through the canal system. The treatment tactics of a dentist rests on clinical data and how many canals are in the tooth.

Organ features

In the process of ontogenesis, already in the prenatal period, the laying of milk and permanent teeth occurs. During the development of the fetus, in parallel with the general growth, an increase in body weight and the complication of the structure of organs and systems, their improvement, mineralization of milk occurs. The permanent group begins to undergo a process of increasing the mineral component in the composition in the first month of life.

Milk teeth or, as they are also called "temporary" (service life is limited), are represented by incisors (central, lateral), canine, first molar and second. A total of 5 on each side of the centerline on the upper and lower jaw. The central line, also known as the "central axis", runs along the apex of the nose, between the central incisors, and up to the apex of the chin. On the upper and lower jaw, 10 teeth should be normal by the age of 3 years.

In the teeth of a permanent group, there are features in anatomical shape and quantity. This is due to the fact that during the growth of the child, the development of the jaw also occurs in parallel with small changes in the skull. The dental arch increases in size, the lower jaw moves down and forward. The permanent group is represented by incisors (central, lateral), canine, premolar (small molar: 2 units), molar (large molar: 3 units). A total of 8 on each side of the center line. Normally, 28 teeth, with the exception of the last "wise" ones, should completely erupt by the age of 15. The remaining eights (the last large indigenous ones) cut through after 18 years.

That for a temporary group, that for a permanent one is characterized by the presence of some similarity in the anatomical structure. The dental organ consists of an outer and an inner part. The external one is visible to us when we smile or when examining the oral cavity on our own in the mirror or when the dentist examines the dentist in a chair at the reception. The inner part is immersed in the bone and is firmly fixed by the periodontal ligamentous apparatus.

If you look at a tooth isolated from the oral cavity, you can see that it consists of three parts:

• Crown;
• Neck;
• Root.

The crown is visible on external examination. The roots are normally buried in the jawbone. The cervix occupies an intermediate position and mainly the periodontal ligaments are attached to it. From the inside, the neck (immersed in the bone) is covered with cement and it is to it that the ligamentous apparatus attaches.

Internal structure

The dental organ is able to perform its function due to the peculiarities of the tissues present in its composition. Outside, cover this organ with enamel, the strongest hard tissue. The thickness of the enamel is very different, depending on the group of teeth and the location of the organ in the jaw arch. Dentin follows the enamel. This tissue takes up a large area of ​​the hard structures of the tooth. Nerve fibers pass through the dentin, the number of which increases towards the border with the pulp chamber.

The inside of the tooth is hollow. If the tooth is roughly divided, then it can be revealed that the root canal of the tooth starts from the pulp chamber, which is represented in a large volume inside the crown. The place of constriction from the pulp chamber into the canal is called the mouth. The number of canals in one tooth root can be different. It should also be noted that different groups of teeth have peculiarities in the structure of the inner part of the tooth.

In milk teeth, the enamel layer is thinner and less mineralized in comparison with permanent ones. This can explain the rapid spread of the carious process deep into the tooth. Temporary dentin is loose and also more represented by organic matrix. The cavity of the root canals is wide, the apical opening (or apex of the tooth) is located at the exit from the root canals into the periodontal region. The stage of formation of the apex ends only three years after the moment of eruption. However, in case of injury, damage to the pulp tissue by an inflammatory process against the background of an infection or other factor, the completion of this stage does not occur. To close the top, a calcium-containing substance must be introduced, due to which the mineralization necessary for this stage is carried out.

Branching system

Why is it important to know how many canals there are in a tooth? Of course, this question does not seem important to a common man in the street, however, for a dentist who is directly involved in the treatment of the problem of teeth with complicated caries (pulpitis, periodontitis), knowledge of the anatomical structure is extremely important. Indeed, even if the infectious process has only partially affected the dental canals, for example, in the area of ​​the upper third, located next to the mouth, the treatment should be carried out efficiently and, preferably, of the entire system. It is extremely rare and only according to indications that amputation is allowed: removal of the pulp from the chamber and partially in the area of ​​the orifices, with the imposition of a therapeutic and insulating pad on the canal itself.

In milk teeth it is presented next system:

• Incisors: both central and lateral have one canal;
• Canine: one long and wide canal;
• First and second molars: usually two.

For a permanent group:

• Incisors: central and lateral in 1 canal (2 can be on the lower one);
• Fang: 1;
• First premolar: 2 at the top, 1 at the bottom;
• Second premolar: 1 on each jaw;
• Third molar: mostly 3, but there may be 4 or more in the upper jaw.

The given information on the number of channels can be considered averaged, since this indicator is collected from the total people previously examined in dentistry. There are individual features of the structure of both the external structure and internal structure. The canals exit from the root of the tooth through the apical foramen. To make it easier for the doctor to rely on how many canals are present in the tooth, other diagnostic methods are also used.

At the doctor

Endodontist dentist directly treats root canals. The restorative part, namely, the restoration of the crown, is performed by a general practitioner, or a narrowly specialized dentist, to replace the part of the tooth visible when smiling.

In order to determine the level of the mouth location, the dentist uses various techniques. At the initial stage, when significant destruction of the tooth crown is detected, the specialist also performs an X-ray examination of the tissue. The sighting contact X-ray shows the topography of the location of the channels. The use of the tabular method is not always informative and accurate, since there are changes in the structure of the canal already inside the root cavity. According to Vertucci's classification, there can be bifurcation and splitting of the canals, while the system can merge into a single point in the area of ​​the apical foramen.

To facilitate the identification of the channels, the doctor uses special fluids in the process of creating access. After the diagnosis is established, treatment begins. Therapy of a diseased tooth consists in the preparation, opening of the cavity, amputation of the coronal pulp, and expansion of the cavity. Then antiseptic treatment is carefully carried out (3% hydrogen peroxide solution, 2% chlorhexidine bigluconate solution), drying. For some time, a liquid is applied to expand and reveal the orifices based on EDTA salts (20%).

In the process of processing, manual, machine endodontic instruments are used, with joint or alternate use chemicals dissolving the smeared layer from the inside of the dentin, the remnants of pulp tissue (3-5% sodium hypochlorite solution). In this case, rely only on anatomical structure system of channels, based on the data in the tables, X-ray studies should not. There are often additional microtubules that extend from the main canals and run towards the dentinoenamel border or apex. Channels are not always available for processing. Areas of narrowing, expansion, curvature may be noted.

After the root canals of the teeth have been thoroughly processed, they proceed to drying and filling. You can fill the canal space with paste, gutta-percha. Gutta-percha is a special material that, when heated, melts and forms a viscous mass that fills all micro-cavities of the tooth. Adequate sealing will prevent the risk of possible re-infection.

Why is it important to understand about the bifurcation system in the tooth?

It seems to the common man that pain in the depths of the tooth may not bother you. However, in case of violation of oral hygiene, an increase in the consumption of rapidly digestible carbohydrates, the absence of a routine medical examination and sanitation of the oral cavity by a specialist, it can lead to the development of caries. Caries is a process that affects the hard tissues of the tooth (enamel, dentin). With deep penetration, the infection from the dentin passes through the microtubule system into the tooth cavity, namely into the pulp chamber. Pulpitis occurs.

Pulpitis is characterized by rapid inflammatory edema, rupture of the neurovascular bundle. In the absence of treatment, the process quickly proceeds through the canal system to the apical region. Thus, provoking periodontitis. Each of the diseases of the hard tissues of the tooth, not complicated (caries) and complicated (pulpitis, periodontitis), has its own characteristics in terms of symptoms, clinical presentation, and, accordingly, treatment. The treatment tactics are specified by a specialist in each case individually. If after filling the pain persists, then it is necessary to inform the attending physician about it. This is important, because mistakes could have been made in the process of diagnosis, treatment, or the patient's condition was not taken into account.

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Endodontics - the section of dentistry that studies the structure and function of the endodontist, the technique and technique of manipulations in the tooth cavity in case of trauma, pathological changes in the pulp, periodontium and for various other indications.

Endodont - a complex of tissues, including pulp and dentin, which are morphologically and functionally related. The pulp and dentin are connected through the processes of odontoblasts, which fill the dentinal tubules (Fig. 9.1).

Clinicians also refer to the endodontist as the pulpoapical complex, which includes the apical periodontium with cement, cortical and cancellous bone adjacent to the apex of the tooth root.

Knowledge of the topography of the tooth cavity, the principles of preparation of the tooth cavity and root canals using modern tools and techniques, materials for filling root canals is the key to successful endodontic treatment and expands the indications for preserving teeth.

Rice. 9.1. Diagram of the relationship between odontoblasts and dentin

Rice. 9.2. Tooth, tooth cavity

Rice. 9.3. Micrographs of the apex foramina

Tooth cavity (cavum dentis)

Its coronal part (cavum coronale) by its structure, it repeats the anatomical shape of the crown of the tooth, and the shape of the root canals - the shape of the roots of the teeth (Fig. 9.2).

The tooth cavity communicates with the periodontium through the main root canal and additional root canals. Additional canals are opened mainly in the area of ​​the apex of the root, or in the middle third of the root, as well as in the area of ​​bifurcation (in molars) (Fig. 9.3, 9.4).

In addition to knowing the anatomy of various groups of teeth, it is necessary to take into account age changes in the structure of the tooth cavity, as well as the influence of pathological processes on its condition.

Rice. 9.4. Tooth tip:

a - X-ray apex

b - physiological apex

c - the apical part of the canal

g - tooth cement

e - dentin of the tooth

e-anatomical apex

The cavity of the tooth in the temporary teeth of children is distinguished by its large size, wide canals and apical foramina.

During a person's life, the shape and size of the cavity changes due to the plastic activity of odontoblasts - the builders of dentin. Often, in older people, the coronal part of the tooth cavity decreases in size, and sometimes completely disappears. The mouths of the canals and the canals themselves become narrowed.

Maxillary central incisor

The coronal part of the tooth cavity is formed by the labial, palatal and two lateral walls, looks like a triangular slit compressed in the vestibular-palatine direction. The arch of the cavity is defined at the level of the middle third of the crown of the tooth with three indentations directed towards the incisal edge. Towards the root, the coronal cavity narrows and becomes a single root canal. The canal of the central incisor of the upper jaw is wide, in the transverse section it is rounded.

Maxillary lateral incisor

The coronal part of the tooth cavity has the form of a triangle. Its widest part is in the area of ​​the tooth neck. The arch of the tooth cavity is determined along the line of the middle third of the crown,

has three depressions directed to the cutting edge, corresponding to its tubercles. The canal is compressed laterally, somewhat narrower than in the central incisors. On the cross section, the canal is elongated in the vestibular-palatine direction and has an oval shape. Often the tip of the root and root canal slightly curved in the palatine direction. An additional channel occurs in 1% of cases.

Canine of the upper jaw

The tooth cavity is spindle-shaped. At the level of the middle of the crown, the cavity expands, and at the level of the neck it is largest. Then the cavity of the tooth, without visible boundaries, passes into a wide root canal. On a cross section, it looks like an oval, extended in the buccal-palatal direction. Often the root and root canal in volume

Central incisor of the lower jaw

The tooth cavity resembles a triangle. The arch of the tooth cavity is located close to the incisal edge.

The coronal part of the cavity smoothly passes into the root canal. Since the root of the tooth is compressed in the mediolateral direction, the cavity of the tooth on the cross-cut has an oval or slit-like shape. The channel is narrow, often poorly passable.

Lateral incisor of the lower jaw

The tooth cavity is slightly larger than the tooth cavity of the central incisor. The canal is oval, extended in the vestibular-lingual direction. The main difference from the central incisor is that the lateral incisor has a wider canal, often two canals are found - the vestibular and the lingual.

Lower jaw canine

The cavity of the tooth, like the tooth itself, has a fusiform shape. There is a depression in the vault corresponding to the cutting tubercle. At the level of the middle of the crown, the cavity expands. It reaches its largest size in the area of ​​the tooth neck, smoothly passing into the root canal. On the cross section, the canal has an oval shape and is compressed in the mediolateral direction. Often there are two canals - buccal and lingual.

Maxillary right premolar

The coronal cavity of the tooth is compressed in the anteroposterior direction, has the form of a slit, elongated in the buccal-palatal direction. It distinguishes: the arch of the tooth cavity, the bottom and 4 walls. The vault of the cavity is located at the level of the neck of the tooth, has two protrusions, respectively, the buccal and palatine tubercles. Cheek protrusion

more pronounced. The bottom of the tooth cavity has a saddle shape and is located much higher than the neck of the tooth, under the gum. Along the edges of the bottom of the tooth cavity, the mouths of the buccal and palatal canals are funnel-shaped. The canals are difficult to pass, but the palatine canal is wider, straight, and the buccal canal is narrower and curved. In 2 - 6% of cases, there are 3 canals: two buccal (anterior and posterior) and one palatine.

Maxillary second premolar

The coronal cavity of this tooth resembles the cavity of the first premolar, is compressed in the anteroposterior direction, has the shape of a slit, elongated in the buccal-palatal direction. The arch of the cavity is located at the level of the neck of the tooth. The coronal cavity without a sharp border turns into a straight, well-passable root canal, the mouth of which is located in the center of the cavity. In 24% of cases, the second maxillary premolar can have two canals (buccal and palatal), which can be connected and opened with one or two apical foramina.

Mandibular first premolar

The coronal cavity of the tooth is oval, narrowed in the anteroposterior direction. There are two depressions in the fornix of the cavity, the larger one corresponds to the larger buccal tubercle, the smaller one to the lingual one. Largest size the cavity is observed below the neck of the tooth. Gradually narrowing, the tooth cavity passes into one pass -

my channel. There may be two canals (buccal and lingual), which can be connected and opened by one or two apical foramina.

Second premolar of the lower jaw

The coronal cavity of the tooth is rounded. In the fornix of the cavity there are two uniform depressions, respectively, the buccal and lingual tubercles. Gradually narrowing, the cavity of the tooth crown passes into one well-passable canal.

Maxillary first molar

In the coronal part of the tooth cavity, which repeats the shape of the crown, there are: the arch, the bottom of the cavity and 4 walls (buccal, palatal, anterior and posterior). On a cross-section, the tooth cavity has the shape of a rhombus. The vault of the cavity is located on the border of the upper and middle third of the crown of the tooth, has depressions, corresponding to the masticatory tubercles. The larger depression corresponds to the larger anterior buccal cusp. The bottom of the tooth cavity is slightly convex and is located at the level of the tooth neck or slightly above it, under the gum. At the bottom of the tooth cavity there are three mouths of root canals: anterior buccal, posterior buccal and palatal, which, when connected, form a triangular

Nick. The base of the latter is formed by a line connecting the mouths of the buccal canals, and the apex is formed by the palatine. The longest palatine canal is usually straight, well-passable, oval in shape.

The buccal canals are narrow, curved, and usually difficult for instrumentation. There is often a fourth canal in the anterior buccal root. As a rule, it has a narrow mouth and is difficult to access for instrumentation. In some cases, it is isolated, and sometimes in the area of ​​the tooth apex it merges with the main canal and ends with one apical foramen.

The second molar of the upper jaw.

There are 4 options for the structure of the cavity of the tooth, according to four options anatomically shaped his crowns. The most common are the first and fourth variants of the structure of the tooth cavity.

The first option: the structure of the cavity repeats the shape of the cavity of the first molar of the upper jaw.

The second and third options are more rare. The cavity of the teeth in these variants has the shape of a rhombus, elongated in the anteroposterior direction.

The canal mouths approach each other and are located almost on one straight line. The arch of the tooth cavity in the second version has 4 depressions, respectively, four cusps. The anterior buccal cavity is more pronounced. The arch of the cavity in the third version has 3 depressions, respectively, three tubercles, the anterior cheek depression is also the most pronounced. The fourth variant of the structure of the tooth cavity has a triangular shape, corresponding to the three-tubercular shape of the chewing surface. The arch of the cavity is projected at the level of the neck of the tooth and has three indentations corresponding to the cusps. The anterior buccal cavity is more pronounced. The bottom of the cavity of the tooth of the second molar of the upper jaw is located above the level of the neck of the tooth. There are three root canals: two buccal (anterior and posterior), one palatine. The palatine canal is wide, well passable, the buccal canal are narrow, curved, often have lateral branches.

Maxillary third molar

The coronal cavity of the tooth is variable in structure, like the tooth itself, often resembling the shape of the cavity of the tooth of the first or second molar of the upper jaw with three canals (two buccal and one lingual). More than three root canals are possible. Often the channels merge into one channel. Due to the structural features and poor access, the third molar presents particular difficulties in endodontic treatment.

Mandibular first molar

The coronal cavity of this tooth has a vault, a bottom and 4 walls (buccal, lingual, anterior and posterior). The vault of the cavity is located on the border of the middle and lower third of the crown of the tooth and has 5 depressions, respectively, five tubercles of the chewing surface. The anterior cheek depression is most pronounced. The bottom of the tooth cavity has a rectangular shape, elongated in the anteroposterior direction. It is located at the level of the neck of the tooth or slightly below and has a convex surface. There are 3 root canal orifices at the bottom of the tooth cavity. There are 2 canals in the anterior root, and one canal in the posterior root. The entrance to the anterior buccal canal is located directly under the tubercle of the same name. The entrances to the anterior lingual and posterior canals are located under the longitudinal fissure separating the buccal and lingual tubercles. The mouths of the canals form a triangle with the apex at the mouth of the posterior canal. The anterior canals are narrow, especially the anterior buccal. The posterior canal is wide, well passable. Often a tooth has 4 canals, of which 2 are located in the anterior root, and 2 others are located in the posterior root. The mouths of the channels in this case form a quadrangle.

The second molar of the lower jaw.

The cavity of the tooth resembles the shape of the cavity of the tooth of the first molar of the lower jaw. However, the roof of the cavity has 4 depressions, corresponding to four bumps on the chewing surface. Compared with the first molar of the lower jaw, the cavity of the tooth is smaller and the distance between the orifices of the root canals is less due to the convergence of the anterior and posterior roots.

Mandibular third molar

The cavity of the tooth is variable in structure, repeats the shape

the tooth itself, often resembles the structure of the tooth cavity of the first or second molars of the lower jaw. However, the number of canals is not constant due to the diversity of the number and location of roots. Roots often grow together to form one canal.

Tooth parameters

(Mamedova L.A., Olesova V.N., 2002)

Table 9.1.

Upper jaw

Lower jaw

Root canal orifice topography

Channel designations:

1 - palatine

2 - anterior buccal

3 - posterior buccal

4 - buccal

5 - anterior lingual

6 - anterior buccal

7 - back

Rice. 9.5. Root canal orifice layout

Rice. 9.6. Topography of the root canal orifices (open tooth cavity is indicated in red)

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The structure of hard tissues surrounding the pulp chamber has numerous configurations and shapes. Thorough knowledge of the anatomy of the tooth, accurate interpretation of axial radiographs, proper preparation access and careful examination of the internal anatomy of the tooth are prerequisites for a successful treatment outcome. Magnification and illumination are aids that must be used to achieve this goal. This article describes and illustrates dental anatomy and discusses the impact of dental anatomy on endodontic treatment. A deep understanding of the complex root canal system is a prerequisite for understanding the principles and problems of formation and cleaning, determining the apical margin and preparation volume, as well as for the successful performance of microsurgical operations.

It is important to have a clear understanding and to know the relationship of internal anatomy prior to endodontic treatment. Careful evaluation of two or more periapical radiographs is imperative. These angled radiographs provide clinicians with essential information about the anatomy of the root canal. Martinez-Lozano et al. Investigated the effect of the angle of inclination of the X-ray tube on the accuracy of determining the anatomy of the root canal in premolars. They found that when shooting at 20 and 40 degrees, the number of root canals observed in the first and second HF premolar and the first LF premolar matched the actual number of root canals. In the case of the second mandibular premolar, only the 40 ° horizontal angle reflects the correct morphology of the root canals. The particular importance of a thorough assessment of each radiograph taken before and during the canal treatment procedure was emphasized by Friedman et al. X-ray examination contributed to the recognition of the complex anatomy of the canals. They caution that any attempt to develop techniques that require fewer x-rays increases the risk of missing out on information that affects treatment success.

Radiographs, however, do not always reflect proper root canal anatomy, especially when only one bucco-lingual view is examined. Nattress et al. Performed radiographs of 790 removed mandibular incisors and premolars to assess the incidence of root canal bifurcation

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How many roots does each tooth have?

The root is located under the gum, below the surface of the neck and makes up approximately 70% of the organ. The number of chewing organs and roots present on them is not identical. A system has been developed according to which they find out how many roots there are, for example, the 6th tooth on top or the wisdom tooth.

How many roots do an adult teeth have? Their number in each chewing unit depends not only on its position, but also on hereditary factors, a person's age, and race. Mongoloids, Negroids have one more roots than Caucasians, but they grow together more often.

Dentists numbered each chewing organ. If you visually dissect the jaw vertically so that the section line passes through the middle of the cranium, then there will be central incisors to the left and right of it. From this area, the organs are numbered towards the ears. If we adhere to this principle of classification, then the root system of the masticatory organs of an adult individual is as follows.

• # 1 and # 2 are called incisors, # 3 are canines, and # 4 and # 5 are called small molars. They grow on the upper and lower jaws and are endowed with one cone-shaped root.
• No. 6 - 7 and No. 8, located at the top, are called large molars and wisdom teeth. Each of them has three bases. The same units, but present on the lower jaw, may have two roots, except for organ no. 8. He has three, and in some cases four.

This information is relevant to the root system of adults. And what about children, what is the number of roots in milk teeth, are there any at all? Many people think that milk teeth do not have them at all. It is not true. They have bases numbering from one to three, with their help the organs cling to the jaw, however, by the time they fall out, the roots disappear, giving rise to the erroneous opinion that they did not exist at all.

How many canals are there in the teeth?

The number of canals in human teeth is not the same as the number of roots. There are two or three of them in the incisor, and maybe one, but it is divided into two. Each person has a unique structure of the dental root system. The exact number of indentations is determined using an X-ray. There are no strict rules in dentistry in this regard, and information on the number of channels is formed as a percentage.

The upper and lower organs are not alike. In the incisors and canines of the upper jaw, one depression. The central incisors of the lower jaw are two-channel. In 70% of cases, he is one, and in the remaining 30% - two.

The second incisor of the lower jaw in 50% of adults has 2 canals, the lower canine in 6% of cases - 1, and in all the rest it is similar to the second incisor.

In the fourth unit, also called the first premolar and located at the top, there are three indentations. However, the 4th upper three-canal tooth is quite rare, only in 6% of people. In 9% of cases, it is one, in other cases - two. A similar four from below does not have more than two channels, more often in it it is found in the singular.

How many canals are there in the top 5 tooth? In the five, called the second premolar, the ratio is similar to that described above. At the top, units with three depressions are found in 1% of individuals, with two in 24%, and in the rest with one. At the bottom of the second premolar, you can often find a single-channel one.

How many canals can be found in the 6 upper tooth? The six on the upper jaw may have three or four of them in the same proportion.

How many canals are there in the 6th lower tooth? At the bottom, sometimes sixes with two indentations come across, in 60% of cases - with three, in the rest we are talking about four-canal teeth.

How many canals are there in a 7 tooth? On the jaw at the top, in 70% of cases, it is endowed with three depressions, in the remaining 30% there are 4 canals in the tooth. In the bottom seven, the percentage is the same.

Is the number of roots equal to the number of channels? No, it’s not like that. The latter have branches, they can bifurcate near the pulp. There are often 2 of them in one root.

In the area of ​​the apex, they tend to bifurcate, then a pair of tops is formed at the root.

Number of canals of the wisdom tooth

How many canals can be found in a wisdom tooth? Organ # 8 is considered extraordinary. If the wisdom tooth is located at the top, it can have five depressions, and at the bottom - no more than three. In rare cases, there are more channels.

Often, the eight gives its owner a lot of trouble. When the wisdom tooth begins to cut, there is strong pain... In the event that he is positioned incorrectly, intense pains appear. For cleaning a wisdom tooth, the use of a special brush is shown, since it is not easy to get to it. In the wisdom tooth, the depressions are often narrow, of irregular configuration, which makes it difficult to carry out therapeutic and diagnostic manipulations.

Why does a tooth need a nerve?

The contents of the dental canals are covered by a network of nerve fibers grouped into branches. Each base is endowed with a branch of a nerve, and often several at once, the branch can split at the top.

How many nerves are there in a molar? This directly depends on the number of roots and channels present in it.

Nerve fibers affect the development and growth of teeth, provide their sensitivity. The presence of nerves allows chewing organ to be not just a piece of bone, but a living organ.

Dental mathematics is very exciting business. Compared to the cost of dental procedures, each molar is worth its weight in gold.

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Anterior temporary teeth

The shape of the root canal of the temporary incisor corresponds to the shape of its root. The bud of a permanent tooth is located more lingually and apically in relation to the temporary anterior tooth. Due to this arrangement of the primordia of the permanent teeth, the resorption of the roots of the temporary incisors and canines begins from the lingual surface of the apical third of the root.

Upper incisors

The root canals of the upper central and lateral temporary incisors have a weakly expressed oval shape. Normally, these teeth have one canal, without bifurcation. Apical accessory and lateral canals are rare.

Lower incisors

The root canals of the lower central and lateral temporary incisors are flattened in the mesio-distal plane. Sometimes there are grooves indicating a possible separation into two channels. In less than 10% of cases, there are two canals, lateral or additional canals occur.

Upper and lower canines

The root canals of the upper and lower temporary canines are similar in shape to the outer outline of the root, resembling a rounded triangle with a base on the vestibular surface. Sometimes the canal lumen is flattened in the anteroposterior direction. The canine root canal system is the simplest of all temporary teeth; these teeth pose the least problems for endodontic treatment. The bifurcation of the channels does not occur normally. Lateral and accessory canals are rare.

Temporary molars

Typically, temporary molars have the same number and location of roots as the corresponding permanent molars. The upper molars have three roots - two buccal and one palatine, the lower molars have two roots - mesial and distal. The roots of temporary molars are thin and long, relative to the length and width of the coronal part. They diverge to the sides, which allows the developing rudiment of a permanent tooth to fit between the roots. By the end of the formation of the roots of temporary molars, each root has only one canal. Subsequent internal dentin deposition can result in a division of the space into two or more canals. During this process, a message remains between the channels, which may remain even after the end of root formation, in the form of an isthmus or gaps.

The most variable is the morphology of the root canals in the mesial root of the upper and lower temporary molars. The reshaping begins at the apex, where a thin isthmus appears between the buccal and lingual walls of the apical canal. With further deposition of replacement dentin, a complete division of the root canal into two or more individual canals can occur. Many fine branches and threadlike messages form a connective network between the buccal and lingual walls of the drip

Similar morphological differences are found in the distal and palatine roots, but to a lesser extent. Quite often, in 10-20% of cases, additional canals, lateral canals and apical branches of the pulp are found in temporary molars.

Root resorption of temporary molars usually begins with inner surface or in the furcation area. The effect of resorption on the root canal anatomy of deciduous teeth is described in detail below.

Upper first provisional molar

The upper first temporary molar has from two to four canals, the shape of which more or less corresponds to the outer outline of the roots (with many deviations). The palatine root is usually round and longer than the buccal roots. The presence of two canals in the mesiobuccal root occurs in about 75% of cases.

In about a third of cases, the palatine and distal buccal roots grow together. These teeth usually have two separate canals with a very thin isthmus between them. Islets of dentin can be located between the canals, with many connecting gaps and anastomoses.

Upper second temporary molar

The upper second temporary molar has two to five canals, the shape of which more or less corresponds to the outer outline of the roots. The drip of the mesio-buccal root usually (in 85-95% of cases) bifurcates, or it contains two separate channels.

Fusion of palatine and distal-buccal roots is possible. In this case, the roots can have a common canal, two separate canals, or two canals with a narrow isthmus, additional islets and many anastomoses between them.

Lower first provisional molar

The lower first temporary molar usually has three canals, the shape of which more or less corresponds to the outer outlines of the roots, but the number of canals can range from two to four. It has been reported that in about 75% of cases, the medial root contains two canals, while the distal root contains more than one canal in only 25% of cases.

Lower second temporary molar

The lower second temporary molar can have two to five canals, but most often there are three. In about 85% of cases, the medial root contains the bottom of the canal, while the distal root contains more than one canal in only 25% of cases.

Diagnostics

Before starting any therapeutic manipulations, it is necessary to conduct a comprehensive clinical and X-ray examination... You also need to take a careful dental and medical history. For a complete diagnosis, sighting and panoramic radiography are required. An obligatory part of the examination is the study of hard and soft tissues in order to identify pathological changes.

In cases where pulp treatment is required, diagnosis is critical and determines the nature of the treatment. If the condition of the pulp was not determined before treatment, and the need for pulp treatment arose during the intervention, an adequate diagnosis becomes impossible.

There are no reliable clinical methods for an accurate diagnosis of the condition of the inflamed pulp. It is impossible to determine the degree of the inflammatory process in the pulp without resorting to histological examination. Diagnosis of the state of the pulp when it is exposed in children is difficult, there is no stable correspondence between clinical symptoms and histopathological state.

Although it is generally accepted that diagnostic tests do not provide an opportunity to assess the degree of pulp inflammation of temporary and permanent teeth with incomplete root formation, they should always be carried out in order to collect the maximum amount of information before treatment.

X-ray

X-ray examination is necessary to detect caries and pathological changes in the periapical tissues. Reading radiographs in children is hampered by the physiological resorption of the roots of deciduous teeth and the incomplete formation of permanent teeth. If the doctor is not well versed in the peculiarities of X-ray diagnostics in children, or if the quality of the X-rays is not good enough, the images may be misinterpreted when normal anatomical features are mistaken for pathological changes.

Radiographs do not always help to identify the pathology of the periapical tissues; the radiograph also cannot accurately determine the depth of the carious cavity. What appears to be an intact secondary dentin barrier covering the pulp in the image may actually be perforated or irregular carious dentin covering the inflamed pulp.

The presence of denticles inside the pulp has a large flow for diagnosing its condition. Mild chronic irritation of the pulp stimulates the formation of replacement dentin. If the inflammation is acute and rapid in nature, the defense mechanism does not have time to work, and secondary dentin is not deposited. When the pathological process reaches the pulp, it tends to develop calcified masses around the affected area. The presence of denticles is always associated with the process of degeneration of the coronal pulp and inflammation of the root pulp.

Pathological changes in the periapical tissues of temporary molars are most often localized in the area of ​​bifurcation or trifurcation of the roots, and not at the apex. Pathological resorption of the root and bone tissue is a consequence of extensive pulp degeneration. Even with similar degenerative changes the pulp can remain viable.

When the pulp of deciduous teeth is damaged, internal resorption often develops. It is always associated with intense inflammation, and usually occurs in the root canals of molars near the bifurcation or trifurcation of the roots. Since the roots of the temporary molars are very thin, the resorption must be strong enough to be seen on a radiograph. Perforation of the root usually occurs as a result of resorption. If root perforation occurs as a result of internal resorption, the temporary tooth cannot be treated. Tooth extraction is the method of choice.

Filling of canals of deciduous teeth

The material for filling the canals of deciduous teeth must be absorbable so that it is absorbed simultaneously with the resorption of the roots, without interfering with the eruption of the permanent tooth. Most of the reports in the American literature concern the use of zinc-oxide-eugenol cements for this purpose, while in other countries pastes based on iodoform (KRI paste, Pharmachemic AG, Zurich, Switzerland) or zinc-oxide-eugenol pastes are used. The antibacterial activity of KRI paste is lower than that of zinc oxide with eugenol, while its cytotoxicity in direct and indirect contact with cells is the same or higher than that of zinc oxide with eugenol. The filling material of choice is zinc oxide eugenol cement without catalyst. The absence of a catalyst is necessary to ensure sufficient working time to fill the channels. The use of gutta-percha or silver pins for filling the canals of deciduous teeth is contraindicated.

Filling of canals of deciduous teeth is usually performed without anesthesia. This technique is preferred because the patient's response serves as an indicator of reaching the apical foramen. However, sometimes it is necessary to numb the gums with an anesthetic solution in order to painlessly install the rubber dam clamp.

Zinc-oxide-eugenol cement is kneaded to a thick consistency and introduced into the tooth cavity with a plastic instrument or canal filler. The material condenses in the channels with pluggers or channel fillers. You can use a cotton ball as a piston, held by the tweezers' brushes, pushing the filling material into the channels. It is also effective to use an endodontic syringe to inject zinc oxide-eugenol cement into the canals. When studying the quality of canal filling and apical obturation, no statistically significant differences were found between canals filled with canal filler, endodontic syringe or plugger.

Regardless of the filling technique, it is important to avoid the removal of the filling material beyond the root apex into the periapical tissues. It has been reported that overfilling with zinc oxide eugenol cement is much more likely to fail than when filling the canal just to or slightly short of the apex. The adequacy of the obturation is verified using radiographs.

If not a large number of zinc-oxide-eugenol cement is still removed from the root apex, it is left as this material will dissolve. It has been reported that defects in underlying permanent teeth are not associated with apex excretion of zinc oxide eugenol cement.

After the canals are satisfactorily filled, a fast-setting, temporary cement or glass ionomer cement is injected into the tooth cavity to isolate the zinc oxide eugenol material. The final restoration can then be carried out. For the restoration of temporary molars, it is advisable to use stainless steel crowns to avoid possible root fracture.

If the rudiment of a permanent tooth is absent, and the pulp of the temporary molar is affected, after extirpation of the pulp, the canals are filled with gutta-percha. Since in this case the factor of eruption of a permanent tooth is absent, gutta-percha becomes the material of choice.

Dispensary observation after extirpation of the pulp of deciduous teeth

As noted above, the success rate after extirpation of the pulp of deciduous teeth is high. However, it is necessary to carry out regular follow-up examinations of such teeth to make sure that the treatment is successful and prevent the development of possible complications. Root resorption should proceed normally, without interfering with the eruption of a permanent tooth, there should be no complaints, the temporary tooth should be well retained in the alveolus, showing no signs of pathology. If pathological changes are detected, it is recommended to remove the tooth and make an appropriate orthodontic appliance to save space in the dental arch.

It has been found that after endodontic treatment, temporary teeth can sometimes be retained in the jaw too long time... One study reported the development of crossbite or palatal eruption of permanent teeth in 20% of cases after treatment of temporary teeth with pulp extirpation. Extraction of the lateral group teeth was required in 22% of cases. displacement of permanent premolars occurred, or replacement of deciduous teeth was difficult. After normal physiological root resorption has reached the level of the pulp chamber, large amounts of cement can slow down the resorption, resulting in prolonged crown retention. Treatment usually consists of removing the crown of the temporary molar, which will allow permanent tooth cut through.

A frequent consequence of the extirpation of the pulp of deciduous teeth is the retention of zinc-oxide-eugenol cement in the tissues. After one long-term study, material retention was reported in 50% of cases after the loss of deciduous teeth. If the canals are not filled up to the apex, the likelihood of material retention is markedly reduced. Over time, the remains of the cement dissolve in whole or in part. The delay in the filling material does not affect the success of the treatment and does not lead to pathological changes. Therefore, no attempt is made to remove residual material particles from the tissues.

Correctly determining the number of canals in a tooth is possible only with the help of an X-ray. Of course, their number depends on where the tooth is located - with a greater chewing load on the teeth in the back of the jaws and the holding system is stronger, respectively, they are larger, have more roots and canals. However, this is a variable indicator, and it does not mean that the upper or lower incisors will have only one canal, it all depends on the individual characteristics of the structures of the jaw of each person. Therefore, how many canals in a diseased tooth require filling, the dentist will be able to determine at an autopsy or using an X-ray.

Percentage calculation

Due to the fact that each person is individual and there are no clear rules and regulations for determining how many canals are in the teeth, in dentistry data on this issue are given in percentage terms. Initially, they are repelled by the fact that the same teeth of the upper and lower jaw are very different from each other. If the first three upper incisors in almost one hundred percent of cases have only one canal, then with the same teeth of the lower jaw everything is much more complicated, and they have approximately the following percentage:

• In the first incisor, most often there is only one canal - this is in 70% of cases from the general statistics, and only in 30% of them there can be two;
• The second tooth, in almost equal proportions, can have either one or two canals, or rather, a ratio of 56% to 44%;
• The third incisor of the lower jaw almost always has only one canal and only in 6% of cases there can be two of them.

Premolars have a larger structure, they are already undergoing more pressure and load, so it is logical to assume that there will be more canals in the tooth, however, and not everything is so simple here. For example, in the fourth tooth of the upper jaw really only 9% of teeth have one canal, in 6% of cases there may even be three of them, but the rest are most often found with two. But at the same time, the next premolar (the fifth tooth), which seems to be subject to an even stronger load, most often has one canal and only in some cases more (of which only 1% falls on three branches).

At the same time, the situation on the lower jaw is completely different - the first and second premolars do not meet three-channel at all, and most often have only one canal (74% - four and 89% - five) and only in 26% of cases for four and 11% for five - two.

Molars are already larger and the number of canals is still increasing. The sixes of the upper jaw with equal probability can have both three and four branches. On the lower jaw, sometimes a two-canal tooth can also be found (usually not more often than in 6% of cases), but most often these are three canals (65%) and sometimes four.

Posterior molars usually have the following ratio:

• Top seven: 70 to 30% three and four channels;
• Bottom 7: 13 to 77% two and three channels.

Eight or wisdom tooth is quite unique and does not fall under the standards and statistics. The upper one can have a completely different structure with channels from one to five. The bottom eight is most often three-channel, however, often during opening during treatment, additional branches can be found.

Among other things, a wisdom tooth differs from others in that its canals are quite rare correct shape, often very curved and with a narrow course, greatly complicating their treatment and filling.

Misconception

Since a tooth consists of roots and a pre-coronal part, sometimes there is an erroneous opinion that there are as many canals in the teeth as there are roots... This is far from the case, because the canals quite often branch off and bifurcate near the pulp. Moreover, in one root several channels can run parallel to each other. There are also cases of their bifurcation at the apex, which is why it turns out that one root has two tops and this, of course, complicates the work of doctors when filling such teeth.

Considering all the features of the individual structure of teeth, dentists need to be very careful during treatment and filling in order not to miss any branch. Indeed, sometimes without an X-ray it is very difficult to reveal how many canals are in the teeth even during an autopsy.

Treatment

The development of modern medicine and dentistry in particular today makes it possible to more and more often preserve those sick teeth that had to be removed yesterday due to the impossibility of treatment. Root canal treatment procedure in the teeth itself is quite complex, because they are filled soft cloth- pulp, which contains a large number of nerve endings, blood vessels and other connective tissues. Today, a separate section of dentistry is engaged in this - endodontics, the development of which makes it possible to improve the condition of human teeth and cure even complex problems in more than 80% of cases, while preserving the tooth itself.

The goals of this treatment are:

• Removal of the developing infection inside the root system;
• Prevention of pulp disintegration or its removal;
• Removal of infected dentin;
• Preparation of the canal for filling (giving it the desired shape);
• Increasing the effect of drugs.

The difficulty of such treatment of the root system is that the dentist is quite difficult to get to diseased canals and monitor the progress of the procedure. After all, if you do not remove even a microscopic part of the infection, it can develop again over time.

One of the main indicators for such treatment is inflammatory process, which leads to damage to the soft tissues of the pulp inside the canals. Most often, various diseases such as caries and pulpitis lead to this, but canal treatment may also be needed for periodontitis.

Tooth pain or swelling of the gums is the first symptom of this treatment. However, it should be borne in mind that in the case of the transition of the disease to chronic stage, pain may not be observed, but the disease develops and eventually leads to tooth loss. This is why it is so important to have regular preventive dental check-ups.

The process and stages of canal treatment

The root canal treatment process has a clear sequence of stages:

If the doctor has any doubts (this usually happens with an inconvenient position of the tooth and difficult access to instruments) - he puts a temporary seal, after which he sends the patient for an X-ray, according to the photo of which he checks whether he has removed all the infection and whether he has cleaned all the channels. A permanent filling is then placed about two weeks after that.

This whole procedure, of course, is not very pleasant, but it allows you to save the tooth. Its duration depends on the location of the tooth, the number of canals in it, the complexity of the infection that has developed and usually takes from thirty minutes to one hour. And success depends on the professionalism of the doctor and the quality work done by him, since it is necessary to remove all the affected pulp from the canals without leaving a single drop of infection, otherwise it can develop again and tightly fill the tooth, so that nothing else could get into the cleaned cavity.

After the procedure for treating the root system for a while stress should be avoided on the cured tooth, moreover, it is impossible to eat earlier than two hours after the therapy, otherwise the incompletely frozen filling may simply fall out. However, the same can happen when the doctor uses low-quality drugs or incorrect treatment (for example, the canals were overdried or not completely dried before filling).

Also, after filling the tooth for some time (up to several days) can give pain when pressed or just whine, cause discomfort, have increased sensitivity. Usually this normal condition pain relievers can be taken if the pain is severe. If the pain does not go away after a certain time, this can also be an indicator poor treatment(insufficient cleaning of infection or infected pulp, leaky filling, use of substandard drugs or materials).

Sometimes there are cases emergence allergic reactions , which is also accompanied by incessant pain, sometimes itching and a rash on the body appears. It can be caused by a reaction to a drug or material used for the filling. In this case, it must be replaced with another one that will not cause allergies.

In all these situations, it is imperative to consult a doctor as soon as possible for a repeated examination and prophylaxis of teeth in order to identify the cause of deviations from the norm.

Each of us at least once, but asked ourselves questions about what constitutes a molar cavity, how many roots and canals there are. What is their topography and anatomy? How many nerves are located in the molar cavity located on top, and how many are in the one below? Root canal working length - what is it? These questions are also relevant for doctors, because the process of their treatment, restoration or removal depends on the number of canals and roots.

Since 1971, there has been a so-called two-digit Viola system in dentistry. According to it, the units of the upper and lower jaw of a person are divided into four quadrants, each of which has 8 teeth. Quadrants in adults are numbered as 1, 2, 3 and 4, and in children - numbers from 5 to 8 (see table). Therefore, if you suddenly hear from the dentist that you are being treated with 46 or 36 units of root canals, do not be alarmed.

Each unit has its own individual structure. The number of canals and roots depends on where it is located and what function it performs. From this article you will learn what a tooth cavity is and why pulpitis affects it. You will also read about the concept of working length of a root canal. You will learn about the methods of expanding dental cavities and their drug treatment, see a photo of three-channel pulpitis.

How does a human tooth work?

The elements of a human tooth can be conditionally divided into:

The crown is located above the gum and has a special coating called enamel. Beneath the enamel is a durable layer of dentin, which is similar in structure to bone tissue.

The cavity of the tooth located inside the crown is called the "pulp". It passes into a narrow root canal, at the base of which there is a small hole. Nerve endings pass through it into the tooth cavity and blood vessels... Inflammation of the pulp is called pulpitis. It is an indication for opening the tooth cavity and cleaning the root canals. The most difficult thing to treat pulpitis is in the cavity of three-channel units (for example, in the sixth). In advanced cases, it is necessary to remove a tooth, and if it is also on top and in the last rows (6, 7 or 8), then it is also inconvenient.

The dental neck is located inside the gum. It does not have an enamel coating, but is protected by cement. A continuation of the tooth cavity is its root. It is located in the alveolus, a small cavity in the teeth. Its structure differs from the structure of the crown and neck. The enamel layer is absent, and the dentin is riddled with collagen. Nerves and blood vessels pass through the root canal into the dental cavity.

Number of roots and canals in teeth

The number of canals differs from the number of root bases. Cavities of teeth such as incisors can have one, two or three canals. In order to accurately determine the number of these dental canals and their location, the doctor makes an x-ray to the patient. He helps him to carry out the procedure of opening the tooth cavity more accurately.

Let us consider in more detail how many canals and roots there are in each cavity. What are the differences in their numbers on the upper and lower jaw?

On the upper jaw

According to a special dental numbering system for root teeth, their counting starts from the central incisors. The upper units, which are numbered from one to five, have one root each, 6, 7 and 8 are three-channel.

In most cases upper incisors and canines each have one canal, the fourth unit (24th premolar) is three-channel in 8% of patients, in other cases there are 2 or 1. Premolar number five (25) may have a different number of channels. In 1% of people this tooth is three-canal, in 24% it is two-canal, and in the rest it is one-canal. The sixth upper tooth (26th molar) can have three or four indentations (in a 50:50 ratio). The seventh root in most cases (70%) is the owner of three channels, but it can also be four-channel (30%).

On the lower jaw

The lower units, from the first incisor to the fifth premolar, have one characteristic feature, which unites them: they all have one cone-shaped root. Then there are “sixes” and “sevens” - they are two-root. The "eights" of the bottom row can have either 3 or four roots.

How many canals are there in the cavity of the lower teeth? So, the central incisors in 30% of cases have 2 depressions, in the remaining 70% - one at a time. The second incisor can be either one- or two-channel (50:50), the third canine in 7% of cases is single-channel. The 4th premolar is found mainly with one root depression, but sometimes with two. The fifth premolar is mainly single-channel. In 60% of cases, 36 molars (6th lower tooth) have three depressions, but there can be 2 and 4. The lower “seven” in 70% of cases has 3 canals, but there are also four.

Wisdom tooth and features of its anatomical structure

The extreme eighth units of the lower and upper jaw are called wisdom teeth. The cavity of these teeth often affects pulpitis, since they erupt very fragile. These curves of the unit of wisdom have a peculiar anatomical structure of the tooth cavity.

They appear later than everyone else: at 20, and at 30, and even at 40 years old. The difference in their anatomical structure lies in the number of roots, which can be from two to five. These roots are quite crooked (see photo), so they cause a lot of problems during treatment procedures, and especially during the determination of the working length, the expansion of the canals and the filling. The number of channels in the "eights" can reach up to five pieces.

How is root canal treatment carried out?

An important step in the treatment of root depressions is to determine the working length of these canals. Not everyone knows the definitions of the length of a tooth root. So, the working length of the root canal is the distance from the edge of the frontal units to the apical narrowing preceding the apical foramen. There are several methods for determining the working length of a root canal. The most often used are the calculation method, X-ray and electrometric methods.

Endodontics is involved in the treatment of root canals. When the endodontist treats the root canal, the manipulations are carried out in the following sequence:

Diagnostic methods

The first stage in the treatment of root canals is diagnostics, which will help the doctor make the correct diagnosis and determine the method of treatment. To do this, the patient needs to undergo an X-ray to examine the part of the crown that the doctor cannot see. This procedure allows you to understand how many roots and canals the tooth cavity has. If the X-ray examination is ignored, then the opening of the cavity of the diseased tooth will have to be performed again.

Preparatory procedures

After the X-ray of the tooth cavity has been thoroughly studied, the diagnosis is made, and the stages of the forthcoming therapy are planned, it is necessary to tell the patient about everything in detail. Next, you need to draw up a documentary consent for the opening and further treatment of the tooth cavity.

An important point in preparation for the treatment of the root socket is the doctor's receipt of information about the presence of allergic reactions in the patient to anesthetics. If such information is not available, then an allergy test is carried out. At this stage, the chemical processing of the instruments is carried out, with the help of which the manipulations will be performed.

Administration of anesthesia and application of anesthetic

Before starting treatment, the patient is anesthetized in the area of ​​the jaw where the intervention will be performed. Anesthesia can be superficial or injected. The first type of anesthesia blocks sensitivity not only in the cavity of the teeth, but also on the mucous membrane. It is usually used to numb the area where the doctor is about to inject the anesthetic.

For superficial anesthesia, the following drugs are used:

Opening the molar

What is the opening of the tooth cavity? In order to remove the pulp and clean the root canals, the dentist must provide good access to them. Opening of the tooth cavity can be started immediately after turning the caries and removing the sawdust from the dentin. The process of opening the tooth cavity begins with the smallest bur, after which a large spherical bur is used.

Drug treatment of canals

Canal treatment is divided into mechanical (scraping of the contents using special tools) and chemical (medical treatment of root canals with disinfectants injected with a thin needle). Today, the following drug treatment scheme for the root canal is used: sodium hypochlorite is applied after using each instrument and completing mechanical cleaning, then hydrogen peroxide, and then distilled water. Medical treatment of root canals is carried out immediately after the opening of the dental cavity is completed.

Filling

The final stage in the treatment of tooth root canals is a hermetic filling of the cavity. Root cavities are filled with a special filling material (usually gutta-percha). The filling helps the tooth to stay strong and prevents pathogenic bacteria from entering its cavity.

Filling of the tooth cavity is:

Prevention of root canal diseases

For an ideal "order" in the oral cavity, you must:

• take care of her properly;
• use quality oral hygiene tools and products;
• visit the dentist twice a year;
• rinse your mouth with water after each meal;
• give up smoking and alcohol;
• reduce the amount of coffee and tea consumed;
• eat properly.

Once I went to the dentistry to treat a tooth, in the end they pulled it out and said that the dentition was wrong. That there should be 3 roots in the tooth, and I have 2. The doctors were mistaken, the root remained in the gum. I got it on my own. And they didn't even deign to double-check everything. So that's it ...

How many canals are in 5, 6, 7 and the rest of the teeth of the upper and lower jaw, what is the length

Teeth differ from each other in shape, structure, number of roots. The space inside the root is called the root canal. The number of roots has a relationship with the load on the tooth, but the number of canals in a tooth does not directly depend on the number of roots. And even in the same tooth in different people, the number of canals may differ.

The key to quality endodontic treatment is precise definition channels of teeth: their number, length, shape.

As a rule, the deeper a tooth is in the mouth, the more canals it has. The number of canals of the teeth of the upper and lower jaw differ: the upper teeth have more of them.

A preliminary assessment of the number of canals in a tooth is carried out according to the table (the probability of a certain number of roots, depending on the location of the tooth):

So, the canals of the 24 tooth (left quadruple on the upper jaw) in 85% of cases are determined by the number 2. That is, there are usually only two canals in this tooth. But 9% of people can only have 1 channel and 6% have 3 channels. On the other hand, 3 channels in the teeth most often (77%) have a "seven" of the lower jaw. With the greatest confidence, one can judge how many channels are in front tooth on the upper jaw - only 1.

It is statistically impossible to answer the question of how many canals there are in a wisdom tooth: in the upper ones, the number varies from one to five, in the lower ones - about three.

The exact number can be found only when opening a tooth or by the results of X-ray (sighting, for a specific tooth, or orthopanthogram, to assess the condition of all teeth).

The length of the canals of the teeth of the upper and lower jaw

For quality endodontic treatment, it is important to know the length of the root canal. The length of the canals of the teeth (table below) depends on the size of the tooth itself. Determination of such parameters is possible in several ways.

The primary preliminary assessment is carried out in a tabular way (the average length of the canal and its variability in mm, depending on the tooth formula):

Sometimes the length of the canals of the teeth can be determined from the radiograph, but the radiographic image in most cases does not reflect the true dimensions.

With an accuracy of 60-97%, the length is determined electrometrically (by changing the electrical resistance of tissues) using an apex locator.

The tactile method is based on slowly immersing the probe into the canal until it becomes jammed.

According to the patient's feelings (a slight "prick" when the instrument is moved beyond the root apex) during treatment without anesthesia, the length of the canal is also roughly determined.

It is effective to use a combination of several approaches.

Root canal patency

In addition to the number and length, important information is the patency of the root canals, which depends on the degree and location of the curvature. If the curvature is less than 25 degrees, then the canal is instrumentally accessible, from 25 to 50 degrees - difficult to access (the so-called difficult-to-pass tooth canals), over 50 degrees - inaccessible. With the localization of the curvature near the mouth of the canal, it is possible to expand the latter and improve patency.

If the examination reveals a too narrow, deep canal in the tooth, a CT scan may be required to clarify its configuration. Treatment of complex teeth requires particularly painstaking work, which can be facilitated with a microscope.

Sometimes the doctor cannot find a canal in a tooth. This situation is usually associated with obliteration (narrowing or overgrowth) of the canals due to an inflammatory or tumor process, incorrect treatment in the past, age-related changes.

Remember that only a specialist can assess the condition of the root canals and, depending on their structural features determine the tactics of treatment.

5 upper tooth how many canals

How many canals are in human teeth? Features of the anatomical structure

A beautiful smile is fashionable. Therefore, great attention is paid to dental health these days. Unfortunately, not everyone can boast of their impeccable appearance, although modern dental developments are able to bring them as close as possible to the ideal.

In our article, we will not talk about this. We will discuss the anatomical structure of the human tooth, the diagram of which is shown on our website.

The molars are the only human organ that cannot be restored on its own. That is why they need to be protected and regularly tracked for any changes in their condition. After all, it is not without reason that a regular examination by a dentist is recommended every 6 months.

The molars require careful maintenance

If we consider it enlarged, then each molar, a photo of which can be seen on our website, consists of a crown and a root part. The coronal part - the one that is located above the level of the gums, is covered from above with the most durable tissue in the human body - enamel, which protects its softer inner layer - dentin, which is the basis of the tooth.

Despite its strength and reliability, enamel is incredibly susceptible to external influences. Poor care and bad habits, and heredity. In the cracks on the enamel fall disease-causing bacteria causing intense tissue destruction. A person develops a carious process, which also captures dentin.

If untreated, the infection penetrates the root part, develops acute pulpitis and other equally dangerous ailments.

As for the structure of the root part. then its main elements are arteries, veins and nerve fibers that feed the tooth. They are located in the pulp of the root canal and through the apical foramen are connected to the main neurovascular bundle.

Dentin below the gum line is covered with cement, which is anchored to the periodontium using collagen fibers. The roots of human teeth, the photo illustrates them very well, are hidden in the alveoli - a kind of depressions in the jawbone.

Any defeat of it requires its complete removal. A broken root cannot be restored.

The structure of the jaw and molars of an adult deserves a separate section. This will be discussed below.

When visiting a dental office, we hear different names that are unusual for our ear and, at times, do not even understand what they are talking about. This section is intended to understand what human teeth are called in order, if necessary, to learn to delve into the degree of dental problems you have discovered.

So, in the mouth we have:

• Central and lateral incisors;
• Fangs;
• Pre-molars or small molars;
• Molars or large molars.

In order to indicate their position on the upper and lower jaw, a so-called dental formula is used in dental practice. according to which the numbers of milk teeth are written in Latin numbers, and the indigenous ones - in Arabic.

With a full set of teeth in an adult, the dental formula will be recorded as follows: 87654321 / 123465678. In total, 32 pieces.

On each side there are 2 incisors, 1 canine, 2 premolars, 3 molars. It is also customary to refer to molars as wisdom teeth, which grow last. As a rule, after 20 years. As for children.

then their dental formula will have a different look. After all, there are only 20 milk teeth.

But we will talk about this a little later, but now we will deal with the structure of incisors, canines, premolars and molars, and also discuss their differences.

Features of the structure of the upper teeth

The smile zone includes the central and lateral incisors, canines and premolars. Molars are called chewable because their main purpose is to chew food. Each of them looks different.

So, the ones are the central incisors. Their coronal part is thickened and slightly flattened; they have one long root. Lateral incisors also have a similar shape. They, like the central incisors, have three tubercles from the incisal edge from which 3 pulp spurs extend along the dental canal.

Fangs are shaped like animal teeth. They have a pointed edge, convex shape and only one tubercle on their cutting part. First and second premolars. or, as dentists call them, the four and the five have a very large external similarity, the difference is only in the size of their buccal surface and in the structure of the root.

Next come the molars. The number 6 has the largest coronal size. She looks like an impressive rectangle, and the chewing surface resembles another in shape. geometric shape- rhombus. The six has 3 roots - one palatine and two buccal.

Seven differs from six in slightly smaller sizes and different structures of fissures, but eight, or, according to folk, a wisdom tooth not even grows in everyone. Its classic shape should be the same as that of ordinary molars, and its root resembles a powerful trunk.

Upper wisdom teeth are considered the most capricious.

They can begin to disturb a person even at the stage of their eruption, and when removed, they can create a difficult situation due to their twisted and twisted roots. On the opposite jaw are their antagonists. Our next section will be devoted to them.

Features of the structure of the lower teeth

What a person's teeth and canines consist of, the photo conveys quite accurately, as well as theirs appearance... It can be judged that the structure of the teeth of the lower jaw is completely different from their structure on the upper jaw. Let's consider this moment in more detail.

The teeth of the lower jaw have the same names as the upper ones, and their structure will be slightly different.

The central incisors are the smallest in size. They have a small flat root and 3 mild tubercles. The lateral incisor is only a few millimeters larger than the central one. It also has a very small size, a narrow crown and a small flat root.

The lower canines are similar in shape to their antagonists, but at the same time they are narrower and slightly deflected back.

The first premolar on the lower jaw has a rounded shape, a flat and flattened root, and some slope towards the tongue.

The second premolar is slightly larger than the first due to the more developed tubercles and the presence of a horseshoe-shaped fissure between them.

The first molar, that is, the lower six, has the most tubercles. Its fissure resembles the letter Ж, moreover, it has as many as 2 roots. One of them has one channel, and the second has two. The second and third molars are very similar in shape to the first.

They are distinguished only by the number of tubercles and fissures located between them, which, especially in the figure eight, can have a bizarre shape.

Milk teeth are the predecessors of molars. They begin to appear in the first year of a baby's life and the first, as a rule, pierces the gum of the lower central incisor. Many parents recall the teething period with a shudder. They give so much torment to the crumbs. This process is not fast - it is stretched out in time.

From the appearance of the first tooth to the last, two, or even two and a half years can pass.

An average three-year-old toddler has a full set of teeth in the mouth in the amount of 20 pieces. A child will walk with them until the age of 11 - 12. But they will begin to change to indigenous from the age of 5 - 7.

Parents keep photos of toothless schoolchildren in family albums. But back to what it is, the structure of milk teeth in children. Let's start with their shape.

It will be approximately the same as that of the permanent ones.

The only difference will be in their small size and snow-white color. However, the degree of mineralization of enamel and dentine is weak, so they are more prone to caries. Therefore, their care must be regular and thorough.

The structure of the milk tooth is also distinguished by a large volume of pulp, which is incredibly prone to inflammation. That is why caries in children is rapidly turning into pulpitis.

Milk teeth do not have long roots. moreover, they do not sit tightly in the periodontal tissue. This greatly facilitates the process of replacing them with permanent ones. Although for children, the process of removing them is always stressful.

Teeth are considered one of the most complex systems our body. Their significance for our a fulfilling life invaluable. Therefore, you need to start taking care of their condition and health from an early age. And make it a rule to visit the dentist every six months.

The number of roots and canals in human teeth

Most of the oral cavity is occupied by organs whose main function is to chew and grind food into smaller pieces.

This contributes to its complete digestion and better absorption. nutrients... A tooth is an organ that has characteristic shape and consisting of several parts.

The outer visible part is called the crown in dentistry, the inner part is called the root. The element connecting the crown and root is the neck.

An interesting fact is that, unlike a crown, a tooth may have more than one root. How many roots a tooth has, as a rule, depends on the location and purpose of the organ. In addition, a hereditary factor affects its structure and the number of roots. The situation can be finally clarified only with the help of an X-ray.

The article provides detailed information on how many roots are in the frontal, lateral chewing teeth, as well as in the figure eight, or the so-called wisdom tooth. In addition, you can find out what is the purpose of the tooth root, for which the chewing units need nerves. The dental advice provided in the following material will help prevent the development of dental diseases.

Number of roots in human teeth

The dental root is located in the inner part of the gum. This invisible part makes up about 70% of the entire organ. An unambiguous answer to the question: how many roots a particular organ does not have, since their number is individual for each individual patient.

Factors affecting the number of roots include:

1. organ location;
2. the degree of load on him, functional features(chewing, frontal);
3. heredity;
4. the age of the patient;
5. race.

Additional Information! The root system of the representatives of the Negroid and Mongoloid races is somewhat different from the European one, it is more ramified than, in fact, and a greater number of roots and canals are justified.

Dentists have developed a special tooth numbering system, thanks to which it is almost impossible for a non-specialist to get confused in the units of the upper and lower dentition. To understand the principle of numbering, it is necessary to mentally divide the skull in half vertically.