Distal bite • Under the distal bite. Anatomical terminology Distal position

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Anomalies of teeth position can occur in isolation, in combination with anomalies of the dentition and bite. Conversely, anomalies in the position of the teeth lead to anomalies in the dentition and bite.

For example: the mesial position of the first permanent molar of the upper jaw with premature removal of the second upper temporary molar leads to unilateral shortening of the upper dentition and the formation of a prognathic bite.

The vestibular position of the lower anterior teeth leads to lengthening of the lower dentition and the formation of a sagittal gap, characteristic of a progenic occlusion.

The etiology of tooth position anomalies and clinical manifestations are different. When diagnosing, data from a clinical and radiological examination of patients, as well as the study of diagnostic models of their jaws, are taken into account. For treatment, the types of orthodontic appliances are selected taking into account the main nosological form of the dental anomaly.

Vestibular position of teeth. The following synonyms are found in the literature: labial or labial position (for anterior teeth), buccal (buccal) position (for lateral teeth).
Moreover, for the anterior teeth such an anomaly will be oriented in the sagittal plane (Fig. 85), and for the lateral teeth - in the transversal plane.

Among the etiological factors are: incorrect location of the rudiments of these teeth, the presence of supernumerary teeth, delay in the dentition of temporary teeth and, conversely, premature removal of temporary teeth and untimely prosthetics, the presence of a chronic inflammatory process in the area of ​​their roots, narrowing of the dentition, incorrect arrangement of teeth on the opposite side jaws.

The vestibular position of the teeth can occur in isolation or be combined with anomalies of the dentition and bite.

In a mixed bite, in order to correct the vestibular position of the teeth, if there is room for them in the dental arch, a removable plate apparatus is used with a vestibular arch (Fig. 86).

When using a vestibular arch, the plastic base of the device, adjacent to the tooth being moved on the oral side, is cut down.

When using a screw for oral movement of a tooth, the unscrewed screw is strengthened in the base of the removable appliance. It is isolated from the ingress of plastic during the manufacture of the device, and also ensures that the guides slide when the screw is tightened. The tooth being moved is covered from the vestibular side with a clasp. In the upper jaw appliance, it is advisable to place the screw in the area of ​​the palate.

In permanent dentition, the Engle sliding apparatus, the Eisenberg apparatus (Fig. 26, b, 28), the Jones apparatus (Fig. 87, a) and the bracket system (Fig. 87, b) are used.

Depending on the stage of bite formation, the first or second permanent molars are used to fix the dental sliding arch. Thin orthodontic rings with horizontal tubes soldered to them from the vestibular side are attached to them. The best treatment results are achieved using the edgewise technique.

Oral position of teeth. The oral position of the teeth is the position of the tooth in which it is located before the dentition, that is, oriented closer to the oral cavity. Synonyms are the definitions palatal (for the upper teeth), lingual (for the lower teeth).

Similar to the vestibular position for the anterior teeth, this anomaly will be oriented in the sagittal plane, for the lateral teeth - in the transversal plane.

Oral position of teeth observed in isolation, in combination with anomalies of the dentition and bite (Fig. 88).

When the anterior teeth are in a palatal position, a deformation of the dental arch occurs, which takes on a trapezoidal shape. This leads to shortening of the anterior segment of the dental arch, close placement of incisors, periodontal diseases, retraction of the lip, and disturbances in the pronunciation of speech sounds.

To treat this anomaly, removable or non-removable mechanically acting functional guides or functional orthodontic devices are used. The degree of reverse incisal overlap is taken into account. According to indications, the bite is separated using occlusal pads on the lateral teeth. To create space in the dentition, expansion of one or both dentitions and removal of individual teeth are used.

In a mixed bite, devices with protraction springs, an expanding screw and a sectoral cut are used. The most commonly used screw is the Planas screw. The small size of the screw and the displacement of its drum to one side make it possible to install the screw in the plate perpendicular to the long axis of the tooth being moved without significant thickening of the apparatus. The cuts can be parallel or converging towards the screw so that the sector does not jam in the base when the screw is unscrewed.

In permanent dentition, among non-removable mechanically operating appliances, the Angle apparatus is used, the Edgewise technique (Fig. 89), and the V.Yu. apparatus. Kurlyandsky (Fig. 42), crown V.Yu. Kurlyandsky (Fig. 40), Katz guide crown (Fig. 39).

It should be noted that the use of functional devices to eliminate the oral position of the teeth is indicated when the depth of the incisal overlap is 1/3 or more, otherwise when the bite is disconnected on an inclined plane located in the frontal area, in the lateral areas of the dentition there is a tendency to vertical movement of the teeth both jaws towards each other. This can lead to the formation of an open bite.

Mesial and distal position of teeth. The distal position of the teeth occurs in the absence of the rudiments of adjacent teeth, in the presence of supernumerary teeth that have erupted into the dentition, and in the case of premature removal of temporary teeth.

If there are indications for distal corpus movement of a tooth, the place of application of force should be brought as close as possible to the apex of its root. For this purpose, a vertical rod is soldered closer to the distal surface of the ring on the fang and its end is brought closer to the transitional fold of the mucous membrane.

Distal movement of the first permanent molars and premolars is indicated for the following anomalies of the dentition: 1. medial displacement of individual teeth, including towards missing temporary or permanent teeth; 2. medial displacement of teeth as a result of bad thumb sucking or other habits; 3. partial edentia; 4. compensatory displacement of teeth on one jaw with a shortened dentition on the other.

For the distal movement of premolars and molars, removable and non-removable mechanically-acting orthodontic appliances are used: removable Schwartz plate appliances with a segmental cut (Fig. 33, b and c), kappa appliances - the Kalamkarov appliance (Fig. 34).

Removable plate devices are made with a variety of springs. Hand-shaped, curled, double springs are used, located on the vestibular and oral sides of the dentition. For unilateral distal movement of the lateral teeth, the screw is installed along the slope of the alveolar process of the jaw so that its long axis is parallel to the lateral segment of the dentition. The canines are located at the turn of the dental arch, so the screw located medial to the canine acts not in the distal, but in the transversal direction. A skeletonized screw with a straight and curved U-shaped guide pin, a distal Weise screw, an expanding Planas screw, and a combined Clay screw are used. On the medial side of the tooth being moved, a single-arm or double-arm clasp is made, the fixing processes of which are located in the small sector of the device. The screw is installed parallel to the alveolar process in the direction of tooth movement.

The Corkhouse sliding strut is a non-removable device. It is strengthened in the area of ​​the early lost primary molar to preserve and create space in the dental arch for the premolar. The device consists of a support ring with tubes on the teeth that limit the defect. When untwisted, the nuts resting on the ends of the tubes shift the supporting teeth in opposite directions.
The Gerling-Gashimov apparatus consists of support rings for the first premolars, a lingual arch soldered to them, and an active part in the form of segments of an Angle arch with a screw thread, soldered to the vestibular surface of the rings for the premolars. Their free end with thrust nuts is inserted into the tubes of the rings for the molars being moved.

R. G. Gashimov proposed, instead of a segment of an Angle arch, for the same purpose, to use small-sized expanding screws that are soldered to the support rings, and also to make an elongated lingual arch in such an apparatus on the side of tooth movement. A short horizontal tube or brackets are soldered onto the ring for the repositioned molar on the lingual side. The free end of the lingual arch is inserted into them, which serves as a guide, preventing the tilt and rotation of the molar being moved.

Gashimov-Khmelevsky apparatus differs in that it is made with two horizontal tubes and two sections from the Angle arc with threads on each side. In order to ensure distal movement of the tooth, adjustable in the vertical plane, in the proposed apparatus, the power rods are rigidly connected to a support ring located on the tooth adjacent to the one being moved, and are installed at different levels. The rod, close to the occlusal area for the tooth being moved, has a nut on its distal side, and the one adjacent to the cervical part has a nut on its medial side.

The guide rod is located on the oral side of the tooth being moved. The device is activated so that the pressure of the lower rod is slightly higher than the tension of the upper rod, which is controlled by the number of turns of the nuts and the clinical result of the impact on the tooth being moved. The tooth moves distally and its movement is adjusted in the vertical plane.

It is possible to move the upper permanent molars and premolars distally using a facebow connected to the dental as well as an extraoral traction supported on the head or neck. For this purpose, rings with horizontal tubes are attached to the teeth to be moved, into which the ends of the dental arch connected to the face bow are inserted. Nuts are screwed onto the ends of the dental arches and installed with emphasis on the tubes. The dental arch should not touch the front teeth. The distance between them of up to 1.5 mm is corrected by unscrewing the nuts. Extraoral traction pressure is transferred to the supporting teeth. If the upper first permanent molars are in cuspal contact with the lower teeth of the same name, then their distal movement does not cause any particular difficulties. More time is required for the distal movement of teeth with incorrect fissure-tubercle contacts between the teeth. Bilateral distal movement of the upper first permanent molars is most effective before the eruption of the second permanent molars, and the second - in the case of congenital absence of the rudiments of the third permanent molars.

It should be taken into account that when moving the upper lateral teeth in the distal direction, i.e. against the direction of natural jaw growth and tooth displacement, complications may arise in the form of unwanted inclination of molars and premolars in the distal or oral direction. To prevent this complication and ensure more corpus distal movement, it is necessary to move the place of application of force in the direction of the roots of the teeth being moved. In the case of using devices with extraoral traction, it is necessary to regularly, at least once every 2 weeks, monitor the closure of the teeth.

Supra- and infraposition of teeth

Anomalies in the position of teeth in the vertical plane are determined in relation to the occlusal plane.

These include supraposition of the upper teeth and supraposition of the lower teeth; infraposition of the upper teeth and infraposition of the lower teeth (Fig. 90).

Incomplete eruption of a tooth may be due to a lack of space for it in the dentition, bad habits, a mechanical obstacle to eruption (supernumerary teeth, temporary teeth retained in the dentition, consequences of injury, disruption of the formation of the tooth root or alveolar process, and other reasons.
Most designs of orthodontic appliances for the vertical movement of individual teeth are used to stretch semi-impacted and impacted teeth, most often incisors and canines.

After creating a place in the dentition on the tooth to be moved, a ring with a hook, bracket, barbell or other device is strengthened and dental-alveolar elongation is promoted using a removable plate apparatus with a spring or non-removable Angle apparatus, edgewise technique, mouth guard, fixed on the teeth of the same or the opposite jaw.

In the case of using a mouth guard or rings, a horizontal rod is soldered on their vestibular or oral side. Its shape and location depend on the direction of movement of the tooth during its extension and the distance over which the tooth needs to be moved. To ensure good fixation of the rubber ring on the rod, notches are made or hooks are strengthened. The teeth are moved using a single-maxillary or intermaxillary rubber traction.

For dentoalveolar shortening, devices are used that increase pressure in the vertical direction on an incorrectly positioned tooth: a plate with springs or a metal band resting on the cutting edge of the tooth being moved or on staples, buttons, hooks soldered to the ring for the tooth being moved, a plate for the opposite jaw with a bite block a platform that separates other teeth.

Rotation of a tooth around its longitudinal axis. Rotation of a tooth around its longitudinal axis can occur as a result of microdentia, narrowing of the dental arches and lack of space in the dentition for individual teeth, early loss of a temporary tooth and displacement of adjacent teeth, incorrect position of the tooth germ, the presence of supernumerary or impacted teeth, bad habits (biting pencil, etc.).

Teeth rotated along an axis can be located in the dentition or outside it. The rotation of the teeth around the longitudinal axis is marked clockwise “positive” (Fig. 93) or counterclockwise “negative” (Fig. 92). The degree of rotation is expressed in degrees and can vary from 1° to 180°.

After creating a place in the dental arch for the axially rotated tooth, it is installed in the correct position using removable or fixed orthodontic appliances, using two counteracting forces. In removable plate devices, a vestibular retraction arch and a lingual protraction spring are often used. Simultaneously with the compression of the loops on the arch, the plastic is cut out at the place where the plate adjoins the oral side of the tooth being moved. When a moving tooth comes into contact with antagonists, the bite should be separated using a bite pad and occlusal pads.

When designing devices for rotating a tooth around an axis, a simultaneous effect is provided on its medial and distal sides in opposite directions. It is advisable to fix a ring with hooks soldered on the vestibular and oral sides on the tooth being moved. The tooth is rotated using a rubber ring. To prevent the stretched ring from slipping onto the cutting edge of the crown, additional hooks are soldered to the ring. Of the non-removable devices, the Angle device is most often used in combination with a ring on a moving tooth, a rubber or ligature traction. The best results are achieved using edgewise techniques.

When orthodontic appliances are used to rotate a tooth around its axis, tension occurs in the periodontal fibers and interdental ligaments, which tend to contract. In this regard, to ensure the effectiveness of treatment, a long retention period (up to 2 years) is required. Premature removal of the retention apparatus may cause recurrence of the anomaly.
Compactosteotomy near the tooth being moved before orthodontic treatment helps to achieve sustainable results after 2 to 3 months. after completion of treatment.
Transposition of teeth. Incorrect position of the teeth, in which the teeth change places, for example, lateral incisors and canines or canines and first premolars is called transposition (Fig. 94). The reason for this anomaly is the incorrect formation of tooth buds.

Treatment for transposition of teeth should be planned after obtaining an x-ray of the area of ​​incorrectly positioned teeth. The choice of treatment method - surgical (removal of individual teeth) or orthodontic - depends on the degree of their displacement and inclination of the roots.

It is advisable to remove teeth that have erupted outside the dentition and are rotated around an axis and have a crown defect, followed by orthodontic movement of the dystopic teeth into the correct position and (or) prosthetic replacement of the defects.

If the upper permanent canine is distally transposed and the primary canine is retained, the primary tooth can be removed and the first premolar moved in its place, placing the canine between the premolars. This method of treatment is effective in the case of a favorable medial inclination of the root of the first premolar. For treatment, depending on the age and severity of the anomaly, removable plate devices with arm-shaped springs and fixed devices of Angle, Pozdnyakova, and edgewise techniques are used.

If orthodontic treatment is inappropriate, orthopedic treatment or tooth transformation using modern composite filling materials is used. These treatment methods involve changing the shape of the crowns of the teeth.

So, when planning orthodontic treatment of dental abnormalities, one should take into account: 1. the availability of space in the dental arch for an incorrectly positioned tooth; 2. depth of incisal overlap; 3. the distance to which the teeth need to be moved; 4. directions of tooth movement; 5. combinations of anomalies in the position of individual teeth and malocclusion in the sagittal, transversal and vertical directions; 6. the period of formation of the bite, the condition of the teeth being moved; 7. method of treatment - orthodontic or combined with surgical, prosthetic, etc.; 8. patient-doctor contact.

The prognosis of treatment and the duration of the retention period are determined by the interdependence between the created shape of the dental arches and the functions of the dentofacial system. After normalization of functions, treatment results are more stable. The designs of retention devices are selected taking into account the direction of tooth movement. Such devices should prevent the teeth from moving to their original position.

Orthodontics
Edited by prof. IN AND. Kutsevlyak

The evidence provided suggests that the efferent copy theory is generally erroneous. We, however, did not talk about what exactly it was wrong with. It is clear that the perceptual system does not combine information about the location of stimulation with information about efferent commands to the eye muscles. This could be the result of the inability of the visual system to combine such information, or it could be a result related to the characteristics of one of these two or both sources of information in question. From the results we have discussed, it seems likely that the perceptual system does not have information about eye movements. It is equally possible that there is no retinal naming system - a way of knowing which part of the retina is being stimulated. It seems that it is here that the solution of particular problems of the ontogenetic development of position perception can lead to its general theory.

The problems we face when studying position perception in adults become much more complex when we move on to study visual perception in infants. As Fig. 3.9), the baby's eye is very different from the adult's eye. It has approximately the same optical characteristics, but is much shorter and has a different radius of curvature. Most importantly, the fovea is located in a different location relative to the optical axis of the eye. A thin beam of light passing through the center of the optical system of an infant's eye will not hit the fovea, but will hit a point 10-15° away from the fovea in the nasal direction (Mann, 1928). As the eye grows, the fovea moves nasally until it occupies the position relative to the optical axis that it has in an adult. Clearly, if the efferent copy theory were correct, infants would have a very inaccurate position perception system. For example, when the eyes of an adult are in a central position and the stimulation is localized in the fovea, then, to a first approximation, it can be stated that the object is located directly in front of the observer's head. For an infant's eye, this combination of conditions would produce an object position offset by 15° from the direction directly in front of the head (see Figure 3.10). It is clear that if there were an innate rule of this kind, children would not be able to localize objects relative to themselves with any acceptable degree of accuracy (until the fovea had assumed an adult position). As we will see, the situation is quite different. Infants detect precise radial localization long before this time. Thus, even if the position of the eye in the orbit is signaled and recorded, there is no way of combining this information with information about the location of stimulation on the retina that would provide an invariant relation suitable for reconstructing any position of objects relative to the observer. The same combination of information about the location of stimulation on the retina and the position of the eye in the orbit will correspond to different external positions of the object at different stages of development.
3.9. Schematic representation of an adult's eye and a newborn's eye. View from above.

Rice. 3.10. For an adult, stimulating the fovea in a central position means that the object is directly in front of the head, but for an infant, the same stimulation conditions correspond to an object shifted relative to the direction directly in front of the head by 15°.
An obvious way to overcome these new difficulties would seem to be to postulate a special calibrating mechanism that could adjust and correct the inaccuracies resulting from the growth process. Some authors (Held, 1965; Kohler, 1964) have proposed the existence of such a mechanism based on their experiments with adults. In their experiments, the apparent distal position of objects, corresponding to some combination of retinal localization and eye position, was changed using some kind of optical device, such as a wedge prism (see Fig. 3.11). When adults began wearing such a device, their radial localization was distorted, but gradually it became normal again. A mountain of literature has accumulated on these corrective processes, indicating the relative contributions of different mechanisms to the process of perceptual adaptation. Both Kohler and Held explicitly argued that similar corrective processes must be involved in the development of direction perception in infants. I cannot agree with this point of view and, in turn, would like to prove that the proposed mechanisms are not even involved in adaptation to prisms in adults! The striking fact is that although adaptation to prisms is usually described as a protracted process, 75% of the total correction occurs instantaneously, as soon as the device is placed on the head and before any hypothetical mechanism can begin to operate (Rock, 1966). . It would be difficult to provide more convincing evidence that distal position is not perceived on the basis of information about retinal place and eye position.
Rice. 3.11. The wedge prism distorts the perception of distal position, which is specified by a combination of information about the location of retinal stimulation and the position of the eye in the orbit.

Definition of disease. Causes of the disease

Distal bite (distal occlusion) is a dentofacial anomaly located in the sagittal plane, in which the upper row of teeth protrudes above the lower row, disrupting their closure. In the structure of dental anomalies today, this pathology occupies one of the leading places and is most often found in children and adolescents from 4 to 16 years old.

The cause of distal occlusion is a discrepancy in the size and shape of the dental alveolar arches as a result of excessive development of the upper jaw, underdevelopment of the lower jaw, or a combination of these two factors.

An oral sign of distal occlusion is that the frontal group of teeth does not close, as the anterior section is lengthened or shortened, and the lateral group does not close correctly due to the narrowing of the corresponding section, which contributes to the formation of a block for the growth of the lower jaw.

The formation of this pathology of occlusion at different periods of development is influenced by a combination of various factors.

According to Professor F. Ya. Khoroshilkina, distal occlusion is formed by endogenous and exogenous factors.

The first group of endogenous factors includes:

• genetic predisposition;
• endocrine diseases;
• disorders of intrauterine development (exposure to negative factors - ionizing radiation, deficiency of vitamins and microelements, use of alcohol, narcotic and psychotropic substances, concomitant maternal diseases).

The second group of factors can be divided into general and local. These factors include:

Distal occlusion impairs the functional ability of the TMJ (temporomandibular joint) and masticatory muscles, resulting in decreased chewing efficiency and TMJ dysfunction. Also, inadequate development of the masticatory muscles can provoke the development of nasal breathing disorders and articulation disorders.

If you notice similar symptoms, consult your doctor. Do not self-medicate - it is dangerous for your health!

Symptoms of distal bite

Symptoms of distal occlusion can lead to aesthetic disturbances due to the appearance of facial signs. Muscle imbalances that occur during distal occlusion affect the formation of the facial skeleton and the tone of the neck muscles. Facial features consist of protrusion of the upper jaw, the formation of a “bird face”, as the chin is sloping, due to this, both the profile and proportions of the face change.

There is a retraction of the lip on the lower jaw and a shortening of the lip on the upper jaw. The frontal group of teeth protrudes sharply forward. With this occlusion, the mouth is not closed, but slightly open; accordingly, the lips also do not close.

In addition to facial signs, there are oral signs, which, in turn, form functional disorders. These include:

• protrusion of the anterior group of teeth of the upper jaw;
• lack of closure between the upper and lower front teeth;
• violation of the closure of the lateral group of teeth in the anteroposterior direction.

Very often, this type of occlusion occurs with other anomalies, for example, with anomalies in the position of the teeth: diastema (gap between teeth) or other bites (open bite).

Distal occlusion provokes dysfunction of the respiratory system, disorders of articulation, chewing and swallowing. Since there is no proper closure of the teeth, it is difficult for the child to bite, chew and swallow food. Mouth breathing and infantile swallowing develop.

Distal bite has a negative effect on the function of the TMJ and masticatory muscles. With this bite, there is an increased risk of the occurrence and development of dental diseases (caries, periodontal problems), as there is excessive pressure on the mucous membrane of the lower front teeth.

Pathogenesis of distal occlusion

The pathogenesis of distal occlusion is closely related to etiological factors.

Infant retrogeny(distal deviation of the lower jaw) is a physiological norm. During the act of sucking, a load occurs on the lower jaw, which subsequently affects its accelerated growth. Incorrect artificial feeding affects the child’s dental apparatus, as a result of which it does not exert proper pressure on the lower jaw and does not push it forward. As a result, the leading factor in jaw growth is missing.

Mouth breathing child is an etiological factor and consequence of various myofunctional disorders. This breathing is formed due to the occurrence of mechanical factors in which nasal breathing is difficult. These include hypertrophy of the inferior turbinates and diseases of the upper respiratory tract. As a result of these obstacles, the distal position of the lower jaw is formed, the tongue is located at the bottom of the oral cavity, and the upper jaw is flattened and narrowed. Thus, a narrowing of the upper dentition in the lateral areas and lengthening in the anterior section is formed, which further contributes to the formation of a larger anteroposterior size of the upper dentition compared to the lower dentition.

Thumb sucking or lip biting are mechanical factors influencing the formation of dental arches. These habits affect the alveolar processes of the jaws and can lead to disturbances in the growth and development of the jaw. Thus, there may be a delay in the growth and development of the anterior part of the lower dental arch and excessive growth of the upper part of the corresponding part of the jaw.

N.I. Agapov points out the negative impact of endocrine diseases, in particular rickets, on the growth and formation of the anterior portion of the lower dental arch. Due to rickets, sagittal discrepancy of the anterior parts of the jaws may occur.

Premature removal of baby teeth can lead to changes in the location of permanent teeth, which also leads to the formation of distal occlusion.

Insufficient physiological abrasion promotes the formation of distal occlusion. In the absence of abrasion, there is no mesial shift of the lower jaw, as a result of which the permanent large molars come into single-tubercular contact with the teeth of the same name in the upper jaw.

Muscle imbalance (relaxation of the masticatory muscles, decrease in its tone) is also involved in the occurrence of distal occlusion. A distal bite can form when feeding a child soft food, which can subsequently lead to incomplete development and growth of the alveolar process.

Classification and stages of development of distal occlusion

Currently, there are a large number of classifications of distal occlusion.

One of the most common and generally accepted classifications of pathological occlusion is the Angle classification. It is based on the relationship of the dentition, which is oriented in the sagittal plane based on the closure of the first large molars. According to this classification, distal occlusion belongs to the second class of malocclusions. With this pathology of occlusion, the mesiobuccal cusp of the upper first large molar is located anterior to the intertubercular fissure of the first permanent molar of the mandible.

Distal occlusion may vary according to the vestibulo-oral position of the frontal teeth. The first subclass is described by the protrusion of the anterior part of the upper dentition and the appearance of gaps between them (trema, diastema). The second subclass is characterized by retrusion (retraction back) of the frontal group of teeth of the upper jaw and dystopia (not fully erupted teeth).

A.I. Betelman divided sagittal occlusion into clinical forms:

• lower micrognathia with normal development of the upper jaw;
• upper macrognathia with a normal lower jaw;
• superior macrognathia combined with inferior micrognathia;
• prognathia of the upper jaw with compression in the lateral areas.

F.Ya. Khoroshilkina divided distal occlusion into three clinical forms:

• Dentoalveolar form. It occurs due to the incorrect location of individual teeth, discrepancy in the size of the teeth of both jaws, discrepancy of the alveolar processes, which as a result is expressed by a change in the normal length of the dental arch and its apical base. This results in retrusion of the lower frontal part of the alveolar process, as well as a forward shift of the lateral group of teeth in the upper jaw.
• Gnathic form. It develops due to the incorrect size of both jaws, as well as due to the inconsistency of their location in the skull.
• Combined form. It occurs as a result of a combination of irregularities in the location of the teeth, discrepancies in the size and position of the jaws in the skull.

L.S. Persin put forward a modern classification and divided the distal occlusion into four clinical types:

• distal occlusion, characterized by excessive development of the upper jaw and shift of the upper dentition forward;
• distal occlusion, characterized by the distal position of the lower jaw and a decrease in the lower dentition;
• distal occlusion, characterized by narrowing of the lateral sections of the dentition, deep incisal occlusion or disocclusion;
• a combination of anomalies of occlusion with anomalies of the teeth and jaws.

Complications of distal occlusion

Distal occlusion affects not only the dentofacial apparatus, but also all systems of the body as a whole. This malocclusion can lead to irreversible structural and morphological changes. Among the main complications are the following:

In addition to dental problems, diseases of other organs and systems may occur: diseases of the ENT organs, digestive organs, cardiovascular diseases.

Diagnosis of distal bite

Diagnosis of distal occlusion involves a complete clinical and paraclinical examination.

Clinical methods include questioning (complaints, life history, medical history), examination, palpation, and functional tests. When examining a person with a distal bite, the “bird face” attracts attention: the chin is sloping, due to which both the profile and proportions of the face change. An oral examination includes examination of the mucous membrane, periodontium and hard palate. Distal bite in the oral cavity is characterized by a sagittal gap of more than 2 mm, as well as the distal location of the lower dentition in relation to the upper one. Palpation of the TMJ indicates functional impairment in the form of discomfort and pain.

The orienting sign is the functional Eschler-Bittner test. With the jaws closed, the person moves the lower jaw forward to the incisal-tubercular contact, after which the facial profile is assessed: improvement in the profile indicates underdevelopment of the lower jaw, and deterioration indicates overdevelopment of the upper jaw.

Paraclinical diagnostic methods include:

• X-ray examination;
• photographing in front and profile;
• taking impressions and obtaining control and diagnostic models;
• assessment of the TMJ condition.

The patient is referred for orthopantomography, teleradiography in the lateral projection. Using an orthopantomogram, the entire dentofacial apparatus, the condition of hard tissues, changes in the periapical areas are examined, and the rudiments of permanent teeth are determined in the temporary dentition. You can also consider the relative position of the teeth in the vertical plane, mesiodistal deviations and the symmetry of the two halves of the jaws. A teleradiogram makes it possible to determine the component of the anomaly (skeletal or soft tissue anomaly.

According to the measurements of the control diagnostic plaster model, the clinical forms of distal occlusion are determined according to F.Ya. Khoroshilkina.

The study of the TMJ is carried out using computed tomography, which allows one to determine the distal position of the articular heads. The joint space in the anterior section is wider, which, when the TMJ is active, can cause its dysfunction.

Treatment of distal bite

Treatment is prescribed after the diagnosis of the underlying and concomitant diseases. The main diagnosis indicates malocclusion, anomalies of individual teeth, anomalies of bone and soft structures. Concomitant diagnosis indicates diseases that are combined with distal occlusion (respiratory diseases).

There are several treatment methods: with the help of devices, orthopedic and orthodontic, surgical, physiotherapeutic interventions, myofunctional exercises.

Treatment of distal occlusion in temporary dentition

From an early age, proper feeding, elimination of bad habits, and elimination of dysfunctions of the respiratory system, swallowing and articulation are necessary.

Treatment of distal occlusion in mixed dentition

During this period, it is effective to prescribe functional devices, among which the following are successfully used:

• Frenkel function regulator;
• activators with screws and facebow;
• devices that promote the advancement of the lower jaw along with myogymnastics.

Also, in case of distal occlusion as a result of macrodentia of the upper teeth, Hotz tooth extraction is prescribed. At 7-8.5 years old, the primary canines on the upper jaw are removed, and at 10-11 years, the permanent premolars are removed to create sufficient space for further eruption of the permanent canine. For upper macrognathia, removal of premolars and distalization of teeth using braces are prescribed.

Treatment of distal occlusion in permanent dentition

In the permanent dentition, the development and growth of the jaws is complete. Treatment is prescribed depending on the clinical form of occlusion:

• for the dentoalveolar form, treatment is prescribed using a brace system;
• with a significant narrowing of the upper dentition, removal of the least valuable teeth is indicated; the use of the Derichsweiler apparatus is possible;

After completion of treatment, a retention period follows (maintaining the achieved result). In temporary dentition, retention is equal to the treatment period. In a mixed dentition, retention should be twice as long as the treatment period. In permanent dentition, the retention period should preferably be 3 times longer than treatment.

Forecast. Prevention

Prevention of distal occlusion is carried out from an early age until the formation of a permanent dentition. Since distal occlusion is formed as a result of a large number of etiological factors at different age periods, preventive measures for this pathology correspond to the patient’s age and type of occlusion.

Prevention of distal occlusion in primary occlusion includes the use of preventive devices: vestibular shield, spinner, Rogers activator, Dass activator.

When this pathology of occlusion occurs in the temporary occlusion, pre-orthodontic trainers and orthodontic structures are prescribed to delay the growth and development of the upper jaw, as well as to prevent the occurrence of narrowing of the dentition in the upper jaw and accelerate the growth of the lower jaw. The following devices can be used: a device with a tongue barrier, a Katz bite block, an Andresen-Heupl activator, an open Klammt activator, Balters, Janson, Khoroshilkina-Tokarevich bionators, a Stockfish kinetor, a Bimler bite former, a Frenkel function regulator and many other devices.

Compliance with all the orthodontist’s prescriptions during treatment contributes to a successful result and elimination of functional and aesthetic problems. To prevent the occurrence of distal occlusion, it is necessary to eliminate all etiological factors:

The most favorable period for the prevention and treatment of distal occlusion is the childhood period, as the jaws continue to grow and develop. In permanent dentition, the dental apparatus is fully formed, which requires longer treatment.

Bibliography

1. Fields HW, Warren DW, Black K, Phillips CL. Relationship between vertical dentofacial morphology and respiration in adolescents. Am J Orthod Dentofacial Orthop. 1991; 99(2):147-154.
2. Abolmasov N.G., Abolmasov N.N. Orthodontics. - M.: MEDpress-inform, 2008. - 424 p.
3. Alimova M.Ya., Grigorieva O.Sh. Features of functional diagnostics of dentofacial anomalies in the sagittal plane // Orthodontics. - 2010. - No. 3. - P. 18-25.
4. Andreishchev A.R. Combined dentofacial anomalies and deformities. - M.: GEOTAR-Media, 2008. - 224 p.

The medial position of the teeth can be a consequence of carious destruction of the crowns of the teeth, early loss of milk or permanent teeth, adentia and other reasons. As a result of the medial movement of the lateral teeth, a shortening of the dentition results.

The lateral position of the anterior teeth and the distal position of the lateral teeth may be due to an obstacle to the medial movement of these teeth (supernumerary teeth, delayed primary molars, wide palatal suture, etc.). The most common anomalies of this group are the gap between the central incisors.

Diastemas and trema.

The first type is the lateral deviation of the crowns of the central incisors with the correct location of the apices of their roots. The causes of this type of diastema are often supernumerary teeth, the eruption of which preceded the eruption of the central incisors, bad habits, sucking of fingers, tongue, etc., pressure with the tip of the tongue on the teeth, which contributes to the appearance of diastema and three between the teeth. The bad habit of biting a nail, pencil or other objects often causes the upper central incisors to rotate along the axis. Incorrect position of the lower central incisor, in particular, its rotation along the axis prevents the installation of the upper incisor in the dentition, which can also cause diastema. Congenital cleft of the alveolar process causes rotation of the central incisor along the axis and its deviation towards the defect. With diastema, the location of the crowns of the central incisors can be different: 1) without rotation along the axis; 2) with rotation along the axis of the medial surface in the vestibular direction; 3) with rotation along the axis of the medial surface in the oral direction. Such variations in the position of the central incisors occur in all types of diastema.

The second type is corpus lateral displacement of the incisors. The causes of this type of diastema can be partial adentia - the absence of a rudimentary or two upper lateral incisors, significant compaction of bone tissue in the area of ​​the median interalveolar septum, low attachment of the frenulum of the upper lip, loss of a lateral incisor, canine or anomalies in their position, the presence of supernumerary teeth - in the area of ​​the central incisors (retained or erupted). The second type is often a family trait.

The third type is the medial inclination of the crowns of the central incisors and the lateral deviation of their roots. Usually observed in the presence of several supernumerary teeth between the roots of the central incisors or a supernumerary tooth located transversely in odontoma, multiple edentia. Sometimes diastema occurs under the influence of not one, but several reasons.

The first and second types of diastema are more common than the third type.

Types of diastema are distinguished on the basis of a clinical examination, study of diagnostic models of the jaws and radiographs of the incisor area according to deviation to the median plane - uniform or uneven or lateral deviation or displacement of rotations along the axis and taking into account etiological and pathological factors.

What are dental anomalies?

Anomalies of teeth are various kinds of morphological and functional deviations from the normal number, size, shape, color, position, timing of eruption, and structure of dental tissues. Dental anomalies are accompanied by deformation of the maxillofacial area, malocclusion, difficulties in biting and chewing food, speech defects, and aesthetic defects. Diagnosis of dental anomalies includes intraoral radiography, conducting and analyzing TRG, panoramic radiography, OPTG, tomography of the TMJ, taking impressions, making and measuring diagnostic models of the jaws, electromyography, etc. The method of treatment is determined by the type of dental anomaly.

Causes (etiology) of dental abnormalities

The causes of anomalies in the position of teeth are varied: disturbances in jaw growth, the process of development and replacement of teeth, atypical formation of tooth buds, a sharp discrepancy in the size of milk and permanent teeth, the presence of supernumerary teeth, macrodentia, etc. The combination of causative factors in various combinations causes a variety of clinical manifestations, which determines the choice of diagnostic methods.

Symptoms (clinical picture) of dental abnormalities

A tooth position that does not correspond to its optimal location in the dentition is diagnosed as a position anomaly. Compared with anomalies in the position of permanent teeth, anomaly in the position of primary teeth is a rare phenomenon.

Teeth may be in an incorrect position within the dentition or located outside it. According to three mutually perpendicular directions, six main types of incorrect position of teeth are distinguished - four in horizontal and two in vertical directions. The teeth can be rotated along a vertical axis. A rare occurrence is such an anomaly as a mutual change in the location of the teeth, for example, in the place of a canine there is a premolar, and in the place of a premolar there is a canine. There are vestibular, oral, distal and mesial position of the teeth, as well as supra- and infraposition, tortoanomaly and transposition of teeth. There are also body displacements and different types of tooth inclination. It should be noted that individual anomalies are a rare occurrence; Typically, tooth malposition is suboptimal in several directions and may be combined with tilt or axial rotation.

Anomalies in the sagittal position of the lateral teeth include the mesial and distal position of the teeth.

Distal displacement of teeth- this is the displacement of the tooth from the optimal one back along the dentition. In the anterior part of the dentition it is called lateral: the tooth is located further from the sagittal plane and relative to its optimal location.

Reasons: partial edentia, atypical position of adjacent teeth, disturbances in teething, changing teeth, atypical position of tooth buds, the presence of supernumerary teeth, etc. Diagnosed by examining the oral cavity. The degree of displacement is determined by the closure with antagonist teeth, as well as by special diagnostic methods.

Mesial tooth displacement- this is its displacement forward along the dentition.

Causes: partial adentia, impaired teething, atypical position of tooth buds, presence of supernumerary teeth, etc. Diagnosed by examining the oral cavity. The degree of displacement is determined by the closure with the antagonist teeth.

Vestibular position of the tooth. The canine is most often displaced towards the vestibule of the oral cavity.

Reasons: narrowing of the dentition, the presence of supernumerary teeth, atypical formation of tooth buds, delayed jaw growth, trauma to the tooth buds, early removal of baby teeth.

The vestibular position of the anterior teeth is characterized by a displacement of the incisors towards the lip.

Reasons: tooth displacement, insufficient space in the dentition, the presence of supernumerary teeth, macrodentia, developmental and teething disorders, tongue function, nasal breathing, narrowing of the dentition, excessive growth of the alveolar process, bad habits.

Diagnosed by examining the oral cavity and jaw models. The degree of vestibular displacement is determined by the alveolar process using symmetrometry, symmetrography, etc.

To clarify the relationship of the dystopic tooth with the erupting teeth, an x-ray examination should be performed.

Oral position of teeth. A distinction is made between the lingual position of the teeth in the lower jaw and the palatal position in the upper jaw.

In the lingual (lingual) position, the tooth on the lower jaw moves towards the tongue. This is most common during the period of changing teeth. More often, incisors and premolars find themselves in this position when there is insufficient space in the dentition and the direction of tooth eruption is incorrect. The diagnostic methods are the same as for the vestibular position of the teeth. In case of lingual displacement of incisors, analysis of jaw models according to Corkhouse is used to clarify the degree of displacement.

The palatal (palatal) position of the tooth is characterized by its displacement on the upper jaw in the palatal direction. The most common reasons are lack of space in the dentition and the wrong direction of tooth eruption. During the period of eruption of primary teeth, it is observed very rarely, mainly in the second half during the period of their replacement and permanent dentition.

The palatal (palatal) position of the tooth in the anterior part of the upper dentition is characterized by displacement of the tooth towards the palate. More often than not, the central incisors find themselves in this position.

The most common reasons are insufficient space in the dentition, underdevelopment of the alveolar process of the upper jaw in the anterior region, bad habits, macrodentia, the presence of supernumerary teeth, disruption of the process of changing teeth, etc. This anomaly is diagnosed during examination of the oral cavity. The degree of tooth displacement is determined by its relationship with adjacent teeth and antagonist teeth, as well as by Corkhouse and teleradiography methods.

Anomalies in the vertical position of teeth. There are supra- and infra-positions of teeth and tortoanomaly.

Supraposition- this is the displacement of the tooth in the vertical direction when the tooth is above the occlusal curve.

Reasons: absence of antagonist teeth in the upper jaw, incomplete eruption of teeth in the upper jaw, excessive growth of the alveolar process in the lower jaw and its underdevelopment in the upper jaw. Diagnosed by examining the mouth. The degree of displacement is set relative to the occlusal plane. The most informative method is teleradiography.

Infraposition- displacement of the tooth in the vertical direction when the tooth is below the occlusal curve.

Causes: absence of an antagonist tooth in the lower jaw, incomplete teething in the lower jaw, excessive growth of the alveolar process in the upper jaw and its underdevelopment in the lower jaw.
Tortoanomaly- rotation of the tooth along the vertical axis. The rotation of the tooth can be of varying degrees: from a few degrees to 90° and even up to 180°, when the tooth is turned with the palatal side, for example, in the vestibular direction.

Reasons: insufficient space in the dentition, incorrect position of the tooth germ, the presence of supernumerary teeth, macrodentia. Diagnosed by examining the oral cavity. The size of the space in the dentition and the degree of tooth rotation are clarified by measuring on models. The relative position of the roots of the tortoanomalous tooth and adjacent teeth is determined on an orthopantomogram.

Transposition- mutual change in the location of teeth in the dentition, for example, a canine in place of a premolar, and a premolar in place of a canine.

Causes: atypical formation of tooth buds. A phenomenon close to transposition is when the tooth buds are displaced mutually as a result of insufficient space or due to provoking factors (supernumerary teeth, odontogenic neoplasms, etc.). In this case, an incomplete change in the relative position of the teeth occurs during eruption, expressed to varying degrees in the area of ​​the roots and crowns.

Diagnosed by examination of the oral cavity, as well as by x-ray.

Very often, an abnormality of the teeth is combined with anomalies of the jaws and leads to an anomaly in the closure of the dentition.

Diagnosis is based on data from the clinical picture, x-ray examination and study of jaw models.

Treatment of dental abnormalities

In case of anomalies in the position of the teeth, the task of the orthodontist is to preliminary normalize the shape and size of the dentition and occlusion. For this purpose, various orthodontic structures are used - both removable and non-removable.

In distal position teeth are moved mesially if there is space in the dentition. The need for mesial tooth movement arises when the first molar is removed (for therapeutic indications), and in this case the second molar moves mesially.

Since this anomaly relates to the lateral teeth, in devices of any design the fulcrum is formed in the anterior or lateral part of the corresponding side, and the point of application of force is the tooth being moved. If a rubber rod is used to move a tooth in an inclined distal position, the point of application of force is the coronal part of the tooth; in the case of a corpus tooth, it is the coronal and root parts, for which a rod with a hook is used in the area of ​​the transitional fold.

In plate devices and mouth guard plastic structures, the fulcrum is hooks welded into the base. In metal structures, hooks are also soldered in the front section on the corresponding structural elements.

Primary and permanent teeth at the appropriate stage of formation can be moved in the mesial direction using hand-shaped springs (according to Kalvelis). Permanent teeth in the final stage of root formation are moved using a brace system both obliquely-rotational and corpusally. To move lateral teeth in the mesial direction, the use of a positioner is ineffective.

Treatment of mesial position teeth are carried out individually. With early removal of the second primary molar or primary edentia of the second premolar of the upper jaw, mesial movement of the first molar is observed. In this regard, the closure of one pair of antagonist teeth is disrupted, namely the mesial-buccal cusp of the first molar of the upper jaw is located in front of the intercuspal fissure of the first molar of the lower jaw. In this case, it is possible to maintain the mesial position of the first molar and then it is advisable to move the second molar forward.

If the doctor decides to move the first molar in the distal direction in order to achieve good closure with the antagonist teeth, you can use a plate on the upper jaw with a sectoral cut, a Kalamkarov apparatus, or an Angle arch. The use of a facebow with cervical traction is especially effective. For the first molars, rings with facebow tubes are made. On the side of the distally moved first molar, a bend is made on the arch, which rests against the tube, and on the opposite side, the end of the arch does not have a stop and is freely located in the tube. In the anterior section, the facial bow is separated from the front teeth. When applying a cervical traction, the entire force of the facebow is directed toward the first molar, which should be moved distally. To move both first molars distally, the facebow has stops in front of the tubes on both sides and both teeth will move distally.

After moving the first molars in the distal direction, the integrity of the dentition is restored at the level of the second premolar using only prosthetics or with preliminary implantation. In the clinic, the mesial position of the lateral teeth is often encountered. This may be due to early removal of the primary canine, high position of the permanent canine bud, the presence of a supernumerary tooth bud, macrodentia of the lateral teeth, a change in the order of eruption of the canine and second premolar (the second premolar erupts first). In this case, the type of closure of the lateral teeth corresponds to Angle class II. To create space for the canine, the lateral teeth must be moved distally. For this you can use plate devices.

Devices 1 and 2 allow you to move the lateral group of teeth on both sides in the distal direction. In this case, the front teeth are moved in the labial direction.

Plate apparatus 3 (a plate for the upper jaw with a sectoral cut) moves the lateral teeth in the distal direction, and apparatus 4 allows, using a vestibular arch with an M-shaped bend, to move the canine in the same direction (the end of the arch is welded into the distal part of the cut). Apparatuses 5 and 7 move molars in the distal direction, and apparatus 6 moves one molar.

The main problem encountered when moving a canine distally is its initial position. The choice of orthodontic apparatus and the direction of the acting force depend on the position of the crown and root parts of the tooth.

Treatment of lateral position of teeth. The most typical clinical sign of such an anomaly is the appearance of a gap between the central incisors - diastema.

The following types of diastema are distinguished:

1) symmetrical diastema, in which there is a lateral displacement of the central incisors;
2) diastema with preferential movement of the crowns of the central teeth in the lateral direction from the midline. The roots of the central incisors retain their position or move slightly in the lateral direction;
3) diastema, in which the crowns of the central teeth have shifted slightly in the lateral direction from the midline, and the roots of the central incisors have shifted significantly;
4) asymmetrical diastema, which occurs when one central incisor has moved significantly in the lateral direction, while the other central incisor has maintained its normal position.

It should be noted that the lateral displacement of the central incisors can be combined with their rotation along the axis of the tooth (tortoanomaly) and vertical displacement of the teeth (dental alveolar lengthening or shortening).

Treatment depends on the clinical picture and causes of the anomaly. If there is a supernumerary tooth germ between the roots of the central incisors, it should be removed. In case of microdentia of the central incisors, the diastema is eliminated only by prosthetics of the central incisors with solid cast or metal-ceramic structures. Such prosthetics are performed in adolescents after 14-15 years of age. In case of diastema caused by microdentia of the lateral incisors, the diastema should be eliminated, and then prosthetics of the lateral incisors should be performed with artificial crowns.

If the upper jaw develops excessively in the anterior region and a diastema occurs, one should try to delay the growth of the upper jaw using a plate with a loop for the treatment of diastema and a vestibular arch. At the same time, the loop and U-shaped bends of the vestibular arch are activated. The canine is removed and installed in place of the missing lateral incisor or moved distally. In the first option, this can be done when the root of the canine is located significantly ahead of its proper place in case of normal eruption. If the mesiodistal size of the canine allows filling the gap formed behind the central incisor, then the cusp of the canine crown can be ground down and given the shape of a lateral incisor. Moving the canine mesially is only possible if the antagonist teeth allow the canine to create normal occlusion with them; otherwise, contact with antagonist teeth (regardless of retention) will result in lateral movement of the canine.

When distal movement of the canine occurs, the gap formed in the area of ​​the missing lateral incisor is eliminated by prosthetics. To do this, you can make a metal-ceramic structure with support on the canine and select the central incisor as the second point of support by making a cusp located on the palatal surface

If the diastema has developed due to the low attachment of the frenulum of the upper lip, they resort to plastic surgery of the low-attached frenulum.

Surgical treatment should begin after the eruption of not only the central incisors, but also the lateral ones, i.e. at the age of 8-9 years. There are cases when, after the eruption of the lateral incisors, the diastema disappears on its own.

If there is a diastema caused by bad habits, it is necessary to wean children from them, and hypnosis therapy is also effective.

With a diastema formed as a result of the abnormal position of the primordia of the incisors and canines, the eruption of not only the incisors, but also the canines is required, after which the diastema may self-remove.

Treatment of symmetrical diastema is carried out with orthodontic appliances, taking into account the size of the gap between the incisors. If the diastema is 3 mm or less, a plate on the upper jaw with a loop for treating diastema or with arm-shaped springs can be used. Activation of the loop is carried out 2 times a week by squeezing the loop with crampon tongs or pliers. You can also use a plate on the upper jaw with two arm-shaped springs covering the incisors from the lateral side, and hooks open to the rear, between which a rubber ring is placed. To prevent rotation of the incisors as they move toward the midline, bend the wire along the palatal surface of the incisors.

When a diastema is combined with deep incisal occlusion or disocclusion, it is necessary to make a bite pad on top of the loop. When treating more pronounced diastema, devices are used that would facilitate the body movement of the incisors and would prevent their rotation during movement. To do this, orthodontic crowns (rings) are used on the incisors with rods soldered to their vestibular surface with hooks open to the rear, between which a rubber ring is placed. To prevent rotation of the incisors when they move, you can solder a horizontal tube to the ring of one of the teeth, and a wire to the other, one end of which will be soldered horizontally to the crown on the vestibular side, and the other should fit into the tube. Thus, the problem of rotation is removed and tension is created for the teeth to move.

When treating diastema with predominant movement of the crowns of the central incisors, the main load of the orthodontic apparatus should be in the area of ​​the coronal part of the incisors. To do this, use a plate on the upper jaw with a loop for the treatment of diastema, arm-shaped springs with hooks open to the back, with a rubber rod placed between them. You can make orthodontic crowns or rings for the central incisors, solder vertically directed rods with hooks open to the rear to them, and put a rubber rod between them.

In case of diastema, when the crowns of the central incisors have shifted slightly in the lateral direction from the midline, and their roots are more significant, it is necessary to create conditions for a more significant movement of the root part of the teeth compared to their crown part. In these cases, a rotational moment is created between the crown and root parts of the tooth for the correct vertical position of the incisors, and only then the diastema is eliminated. For this purpose, crowns or rings are made for the central incisors, and rods are soldered vertically on the vestibular side. The upper end of the rod should be extended and end with a hook, open back at the level of 2 tooth roots or K from the top of the tooth root. Then a stable Angle arch is applied to the dentition, to which a hook open to the rear is soldered in the canine area on the opposite side of the dentition. When an oblique rubber rod is applied, the tooth root experiences a load in the mesial direction, but the tooth does not rotate, since there is no second rod in the opposite direction. To do this, the lower hook from the bar is open forward, from it a rubber rod will go to the hook, open back, which is soldered to the Angle arch in the canine area on the same side of the dentition.

Instead of an arch, a plate on the upper jaw with Adams clasps on the first molars and button clasps located between the first and second premolar on both sides of the dentition can be used as a support. The ideal technique to correct this anomaly is braces.

When treating an asymmetrical diastema, which occurs when one central incisor is displaced laterally, only this tooth should be treated. The choice of orthodontic technique depends on the position of the central incisor, which can be different: parallel with an offset from the midline, when the root and crown of the tooth are displaced the same distance from the midline; the crown of the tooth is displaced more significantly than its root, the root of the tooth - more significantly than its crown. Lateral displacement of the central incisor can be combined with its tortoanomaly, as well as with dentoalveolar lengthening or shortening.

With this form of diastema, the central incisor, which is normally located, can serve as a fulcrum when moving the abnormal incisor. To eliminate an asymmetrical diastema, a plate can be made for the upper jaw with a hand-shaped spring covering the moving incisor from the distal side. As a support, Adams clasps are used on the first molars, button clasps and a round clasp on the central incisor, located correctly. You can make an arm-shaped spring with hooks open back, and put a rubber rod between it and the second hook located on a round clasp and also open back.

For a more pronounced diastema, a crown or ring is made for the tooth being moved with a guide tube, as described above.

Very often, diastema is accompanied by protrusion of the upper front teeth. In this case, along with treatment of the diastema, the anterior portion of the upper dentition should be flattened. For this purpose, it is more correct to make a plate for the upper jaw with arm-shaped springs on 1|1 to correct the diastema and a vestibular blowout with U-shaped bends with a vinyl chloride coating.

In recent years, orthodontic devices - positioners - have been used to eliminate diastema in dental practice.

Treatment of vestibular position of teeth. Permanent teeth with formed roots are moved from the vestibular position with an Angle arch, and depending on the combination with anomalies in the size and shape of the dentition, both a stationary and a sliding arch are used. Since the bracket system is universal, it is intended to use its design features to normalize the position of permanent teeth in the vestibular position. At the appropriate stage of formation of the roots and periodontium of permanent teeth, it is possible to use a positioner.

Normalization of the position of the anterior teeth located vestibularly is carried out, as is the normalization of the position of the lateral teeth. However, the morphological, functional and topographical features of the anterior teeth determine the possibility of using devices of specific designs and different combinations of their structural elements. Thus, vestibular retracting arches are widely used in children with baby teeth and during their replacement period. Naturally, the design of the device is determined by a complex of clinical manifestations.

One of the features of normalization of labially located upper teeth is also the use of a face bow. It should be said that the use of positioners to eliminate the labial position of the anterior teeth is more effective than when moving other teeth.

Treatment of the vestibular (labial) position of the lower front teeth is carried out with a retracting arch with vinyl chloride coating in the presence of three and diastema between the teeth.

If there is protrusion of the lower front teeth and the absence of three and diastema between them, one should take the path of removing complete teeth (usually the first premolars). The choice of treatment method depends on the size of the teeth and the type of closure of the first molars and canines. The canine often occupies a vestibular position, which is called dystopia, and it is necessary to determine whether there is a place for it in the dentition. Canine dystopia can occur as a result of disturbances in the eruption of teeth and the sequence of their eruption. Thus, very often after the eruption of the first premolar of the upper jaw, the eruption of the second premolar, and not the canine, follows. In this regard, and taking into account the mesial position of the teeth when they erupt, the canine has no place in the dentition and it erupts either in the vestibular or oral direction.

Dystopia of the canine occurs with macrodentia of the upper front teeth, which take the place of the canine. It can also occur in the presence of supernumerary teeth, narrowing of the dentition, early removal of the primary canine (in this case, mesial displacement of the lateral teeth occurs). Clinically, the mesial shift of the lateral teeth can be determined by the closure of these teeth with the antagonist teeth. On this side of the dentition, the closure of the lateral teeth occurs according to Engle’s class II, and on the opposite side - according to class I.

In case of canine dystopia, it is necessary to find out whether there is a place for it in the dentition. If there is one, then there is only one task: to place the canine in the dentition. To do this, you can use a plate on the upper jaw with a vestibular arch and an M-shaped bend on the canine. When the M-shaped bend is activated (plastic is first cut out from under the canine on the palatal side), the canine experiences increased load and moves in the oral direction.

Teeth are moved from the vestibular position using a rubber rod and springs, arches, even screws. Moving with a screw involves placing it in activated form on a plate with a sectoral cut, which has clasps or a multi-link clasp on the moving teeth, as well as additional Adams or round support clasps on the opposite side. By activating the screw, i.e. returning it to its original position, the necessary movement of the teeth is achieved.
When moving teeth using a rubber rod, a ring or crown with a hook, or a bracket is fixed on the tooth, which is the point of application of force, and the fulcrum is the hook in the base of the device.

If there is dystopia of the canine and there is no place for it in the dentition, a place should be created for it. If there is no space for a canine due to mesial displacement of the lateral teeth, they should be moved distally. Distal movement of teeth is possible in the absence of a wisdom tooth germ. For distal movement of teeth, a plate apparatus with a sectoral cut, a face bow, a Kalamkarov apparatus, and arm-shaped springs are used.

If there is a rudiment of a wisdom tooth, macrodentia of teeth, one should follow the path of removing a complete tooth in order to create a place for a canine. Most often, for orthodontic reasons, the first premolar is removed; in the presence of caries and destruction of the crown of the tooth, the second premolar and even the first molar can be removed. When removing a tooth, attention should be paid to the passage of the midline between the incisors, and the choice of the tooth to be removed should be such as not to aggravate the asymmetry of the position of the incisors of the upper and lower jaws.

Treatment of oral position of teeth should include normalization of the position of the tooth and its placement in the dentition. It is necessary to find out whether there is room for this tooth. If there is space, the tooth or group of teeth is moved using orthodontic appliances.

If the upper anterior teeth are in a palatal position, a plate is made for the upper jaw with a sectoral cut or protracting springs. A stable Angle arch can be made and by activating the ligatures or nuts the teeth will be moved in the labial direction. When the upper incisors are in a palatal position, Bynin and Schwartz mouthguards and a Reichenbach-Brückle plate with an inclined plane are used. The use of a positioner with a preliminary setup system is also shown.

In case of crowded position of the lower front teeth and their lingual position, which arose as a result of macrodentia, it is advisable to take the path of removing complete teeth. First you should pay attention to the passage of the midline. The tooth to be removed can be a central or lateral incisor, as well as a first or second premolar. It all depends on the lack of space in the dentition and the location of the lower incisors in relation to the midline. If the space deficit is greater than the size of the incisor, and the midline is not displaced, then the abnormally located tooth is removed. If the midline is displaced to one side or the other, then the tooth on the opposite side of the midline displacement is removed.

The question of removing the first or second premolars is decided depending on the lack of space, taking into account the violation of the closure of the lateral teeth.

It must be remembered that the removal of any incisor on the lower jaw leads to aggravation of the depth of the incisal overlap.

When the upper or lower teeth are in an oral position, the closure of the dentition is disrupted. Thus, with a palatal inclination of the upper anterior teeth, a deep incisal occlusion is formed. This is typical for class II of the 2nd subclass of Angle. Otherwise, it is distal occlusion of the dentition in combination with palatal inclination of the upper incisors. With a significant palatal position of the upper incisors, reverse incisal occlusion, or disocclusion, is formed.

In this case, it is necessary to take into account the separation of the dentition in order to eliminate blocking of the upper and lower incisors. For this purpose, plate devices are made with occlusal linings in the lateral areas of the dentition. To eliminate the pressure of the orbicularis oris muscle on the upper incisors, it is necessary to make a labial plastic bandage. You can separate the dentition using mouth guards or orthodontic crowns.

In palatal position For upper lateral teeth, it is advisable to use a plate on the upper jaw with a sectoral cut and occlusal overlays on the opposite side of the dentition. When combining the palatal position of the upper incisors and the mesial position of the lateral teeth, it is necessary to either move the lateral teeth distally or remove complete teeth (usually the first premolar - one or both sides). Thus, a place is created in the dentition for the frontal teeth, after which they are moved in the labial direction.

Very good results are achieved when treating crowded lower anterior teeth with a lip bumper. This device allows you to change the myodynamic balance between the orbicularis oris muscle and the tongue muscles.
Treatment of anomalies in the vertical position of teeth involves reducing or increasing the dento-alveolar height in the corresponding section. Reducing the dento-alveolar height is achieved by creating vertical loads on the corresponding teeth to induce the process of bone resorption.

Dental alveolar elongation in the area of ​​one tooth or a group of teeth may be associated with the absence of antagonist teeth or the presence of bad habits. Dentoalveolar elongation of the lateral teeth of the upper jaw is often observed, which leads to vertical incisal disocclusion. Dentoalveolar elongation of the lower anterior teeth leads to deep incisal disocclusion or occlusion. When dentoalveolar lengthening of the lateral teeth occurs, they should be introduced.

Treatment is carried out with a plate on the lower jaw with occlusal pads, and dentoalveolar lengthening of the lower anterior teeth is carried out with a plate on the upper jaw with a bite pad. An Andresen-Goipl monoblock and positioner are used.

When dentoalveolar lengthening of one tooth is carried out, it is implanted and then an apparatus is necessarily made for the opposite dentition with an artificial antagonist tooth.

When the tooth is suprapositioned, there is another task - to increase the dentoalveolar height in the corresponding section as a result of bone building. This is achieved by physiological irritation by applying a rubber ring and creating traction that transfers the load through the periodontium to the bone structures. The point of application of force is a hook on a ring fixed to the tooth being moved (crowns or braces are possible), the fulcrum point is a hook on a mouthguard blocking antagonist teeth, or a hook in the design of an apparatus used in complex treatment. At the end of the change of teeth and after it, you can use a bracket system, as well as a stationary Angle arch. It should be noted that after eliminating such an anomaly, a long retention period is usually required.

Treatment of tortoanomalies involves the creation of a pair of forces directed in the directions opposite to the rotation of the tooth. This is achieved by creating two points of force application on the crown of the tooth being moved. The points of application of force can be hooks on rings, crowns or braces, and the points of support can be hooks on aligners blocking groups of teeth, or fixed in basic devices. When elastic rings are applied, a pair of multidirectional forces is created, which leads to normalization of the tooth position. It is extremely important to maintain constant optimal traction. Tortoanomaly is also eliminated with the help of positioners.

At the end of the change of teeth and after it, the tortoanomaly can be eliminated using a brace system or an Angle arc, if there are other indications for their use.

Treatment of tooth transposition

If such an anomaly is present in the area of ​​the front teeth, the cosmetic and functional effect is often achieved by grinding (for example, when there is a canine in place of the incisor). Depending on the combination of clinical factors, it may be preferable to restore the optimal shape of the tooth using an orthopedic crown. In the area of ​​the lateral teeth, grinding is usually sufficient.

Problems arise when there is transposition of the teeth and these teeth are abnormally positioned. For example, in the place of the canine there is a first premolar, the canine is vestibular at the level of the first premolar, and in the dentition there is a second premolar (in place of the first premolar), then the first and second molars. If there is a rudiment of a wisdom tooth, it is necessary to remove the vestibular canine. In the absence of a wisdom tooth rudiment, distal displacement of premolars and molars and movement of the canine in the dentition to its place are possible.

Distal movement of teeth is carried out using a plate with a sectoral cut, arm-shaped springs, a Kalamkarov apparatus, a face bow, and a positioner.

It should be noted that dental anomalies lead to anomalies of the dentition and anomalies of occlusion.

Which doctors should you contact if you have dental abnormalities?

• Dentist