home Audience 3 Excessive vertical development of the upper jaw. Anomalies in jaw size

Excessive vertical development of the upper jaw. Anomalies in jaw size

Anomalies of development and deformation of the jaws

The word “anomaly” (anomalia - unevenness) means irregularity, deviation from the norm. In relation to the jaws, anomalies are defined as a violation of their growth in the direction of excessive or insufficient development. Anomalies of the jaws are not only accompanied by a violation of the facial configuration, but also cause a number of functional disorders - chewing, speech, breathing.

Most jaw deformities occur due to various diseases during the development of the facial skeleton (osteomyelitis, arthritis of the temporomandibular joint, rickets), trauma, early operations for cleft palate, cicatricial deformities after burns, etc.

Congenital deformations of the jaws are extremely rare and serve as a manifestation of general underdevelopment of the head and facial skeleton with certain developmental defects (maxillofacial dysostosis, congenital transverse and oblique facial clefts, etc.). The causes of some deformities remain unclear.

Early orthodontic treatment can in most cases eliminate the deformity or prevent its further development. However, correction of some jaw deformations, especially during the period of formed permanent dentition, requires complex treatment, including surgical and orthodontic techniques. Surgical intervention is planned in advance, taking into account anthropometric measurements, studying radiographs and checking the relationship of the dental arches on plaster models after they have been cut and moved to a new position. Surgery indicated at the age of 15-17 years, when the formation of the facial skeleton is largely completed.

The most common jaw deformities are microgenia, progenia, micrognathia, prognathia and open bite.

Microgenia- unilateral or bilateral underdevelopment of the lower jaw. Underdevelopment of the lower jaw can be congenital or acquired. In practice, most often we have to deal with acquired microgenia, which has developed due to damage to the growth zones located in the head of the condylar process. The main causes of such damage to growth zones are osteomyelitis of the lower jaw, purulent inflammation temporomandibular joint, mechanical damage condylar process in early childhood. Acquired microgenia often accompanies ankylosis of the temporomandibular joint.

With bilateral microgenia, the chin moves back, causing facial disfigurement known as “bird face.” There is a malocclusion in the form of a deep incisal overlap.

With unilateral microgenia, the chin is shifted to the affected side, the soft tissues of the cheek on the affected side are convex, and on the healthy side they are flattened. When you open your mouth, facial asymmetry increases.

Microgeny is accompanied by significant secondary deformation upper jaw: the alveolar process and dental arch on the healthy side sink inwards, the front teeth move forward in a fan-shaped manner. This combination of damage to both jaws in most cases provides compensation for the bite, while simultaneously causing a significant disturbance in the configuration of the face.

Combined damage with microgenia requires complex treatment, aimed not only at surgical lengthening lower jaw, but also to correct secondary deformations of the upper jaw. To eliminate microgenia, two groups of surgical interventions are used: surgical interventions that change the external contours of the face; surgical interventions on the bone to lengthen it.

The first group of surgical interventions is designed only for a cosmetic effect. To do this, plastic materials are implanted on the flattened side of the face. Contour plastic surgery is used with crushed autocartilage or allogeneic cartilage, injected into the tissue using a special revolving syringe (Alla A. Limberg). For unilateral microgenia, crushed cartilage is distributed in the area of the body of the lower jaw on the healthy side, and for bilateral microgenia, it is distributed in the chin area. KK Zamyatin uses crushed granulated fluoroplastic-4 plastic as a plastic material for contour plastic surgery. To do this, he developed a special apparatus that makes it possible to form granules with a diameter of 0.3 to 2 mm from plastic tapes of standard width and inject them into tissues through an injection needle without preliminary dissection and delamination of the latter. Among the crushed plastic, vascularized fibrous tissue is formed, which, surrounding and isolating the granules from each other, at the same time unites them into a single monolithic implant. Connective tissue it plays the role of stroma, the cells of which contain fluoroplastic granules. Each granule is surrounded by a thin connective tissue capsule.

In case of pronounced microgenia, more complex surgical interventions are resorted to, aimed at lengthening the lower jaw.

All proposed methods for lengthening the lower jaw can be divided into two groups: 1) lengthening by plastic osteotomy; 2) lengthening by vertical osteotomy with bone grafting. There are many different types of plastic osteotomy (horizontal, vertical, step-shaped, oblique, arcuate, etc.).

The Moscow Medical Dental Institute has developed a step-shaped osteotomy in the area of the jaw branch. An incision is made at the angle of the lower jaw, its branch is exposed, and then a step-like osteotomy is performed within the middle third. The lower jaw is placed in the correct position and its fragments are fixed with a wire suture. A step-shaped osteotomy is often performed in the area of the jaw body. IN last years More successful modifications of step-shaped osteotomy in combination with longitudinal bone splitting have been developed.

With preserved teeth, O. A. Svistunov proposed making a horizontal cut below the mandibular canal. With this technique, the teeth are not damaged and the neurovascular bundle can be preserved.

Lengthening the lower jaw by plastic osteotomy is difficult in some cases due to the sharp thinning of the jaw body on the affected side.

In these cases, a vertical osteotomy of the body of the lower jaw is performed from the primary bone grafting the resulting defect. Surgical treatment of microgenia gives good anatomical and functional results only in cases when it is combined with early orthopedic treatment and subsequent rational prosthetics.

Progenia is characterized by an enlargement of the lower jaw with protrusion of the chin and malocclusion. The bite has an inverse relationship between the front teeth, between which there is no occlusal contact. With this deformation, along with a sharp violation facial configuration, chewing function, especially biting, is significantly reduced.

There are false and true progeny. With false progeny, the relationship of the dentition is changed only in the frontal region in the form of the lower teeth overlapping the upper teeth with a neutral relationship of the first large molars. It is customary to distinguish between two forms of false progeny: frontal, caused by underdevelopment of the anterior part of the upper jaw, and forced, resulting from habitual displacement lower jaw forward. The latter circumstance may be caused by a narrowing of the nasopharynx, which leads to the appearance of compensatory devices that make breathing easier, but at the same time disrupt the normal statics of the lower jaw in the form of its constant extension. This constant protrusion of the lower jaw can ultimately lead to a violation normal ratios dental arches and their shapes.

It is possible to develop progeny as a result of bad childhood habits (sucking the upper lip, laying the tongue on the vestibular surface of the upper incisors, etc.). In this case, the incisors of the upper jaw are shifted towards the palate, the development of its anterior section is inhibited, which leads to false (frontal) progeny.

With true progeny, all dimensions of the lower jaw are increased and, accordingly, the relationship of the entire dentition is disturbed. This type of anomaly has been observed in members of individual families for a number of generations, and also occurs as a result of acromegaly.

In the treatment of progeny, they are mainly used surgical methods aimed at shortening the lower jaw. Before surgery, patients undergo comprehensive examination. Along with examining the teeth, oral mucosa, nasopharynx, and bite, indicators are studied anthropometric measurement faces, photographs and plaster masks of the face, plaster models of the jaws and tele-radiographs. The size of the required shortening and posterior shift of the lower jaw is determined by measurements not only on the patient, but also on plaster models of the jaws. The proposed options for the operation are first reproduced on copies of lateral teleroentgenograms of the skull. Having obtained the correct facial profile with normal incisal overlap, the doctor reproduces the optimal version of the operation on plaster models, and then performs it on the patient. The success of treatment in all cases depends on the thoroughness of the preoperative examination and planning of the upcoming operation using teleroentgenograms and models of the jaws. To eliminate progenia, several surgical options are used.

Horizontal osteotomy of the branch. In this operation, a skin incision is made below the angle of the lower jaw. A horizontal osteotomy is performed corresponding to the level of the border of the upper and middle third of the jaw branch. At the same time, the posterior edge of the jaw ramus is reserved. The lower jaw is placed in the correct relationship with the upper jaw and the fragments are fastened with a bone suture (Fig. 194).

On the side of the oral cavity, the lower jaw is fixed with wire splints with intermaxillary traction for 1.5 months.

Vertical osteotomy of the mandibular ramus. Trauner (1953) proposed an L-shaped vertical osteotomy. After osteotomy, two fragments are formed - large and small. The large fragment is shifted posteriorly, placing it medially from the small fragment. The contacting surfaces of the fragments are freed from the cortical layer and fixed with a wire suture.

V. F. Rudko performs a vertical osteotomy of the lower jaw branch with simultaneous removal of the wedge-shaped portion of the bone. The size of the wedge-shaped area to be removed depends on the amount of posterior movement of the lower jaw required.

Operations on the body of the lower jaw. Most often, surgical intervention is performed on the body of the lower jaw. Shortening the lateral parts of the body of the lower jaw can be done by bilateral osteotomy of the jaw with removal of a section of bone.

A.E. Rauer developed a bilateral step-shaped osteotomy in the area of the body of the lower jaw with resection of a section of bone and preservation of the neurovascular bundle. The bone fragments, after being displaced posteriorly and brought closer together, are fixed with wire sutures.

Surgical treatments for progenia tend to produce better results if they are combined with orthodontic treatment before and after surgery.

Open bite. This deformity is characterized by a lack of closure between the front teeth. In the most severe cases of open bite, when the jaws are closed, contact occurs only between the last molars. Lack of teeth closure reduces chewing efficiency and disrupts the pronunciation of certain sounds. An open bite most often occurs due to rickets. An open bite may occur after improperly healed fractures of the upper and lower jaw, as well as after surgery for bilateral ankylosis of the temporomandibular joint.

The choice of treatment method for open bite depends on the severity of the deformity and the age of the patient. In childhood, treatment can be successfully limited to orthodontic methods. In adults, when the bite is formed and jaw growth is complete, surgical treatment methods are used. Surgical intervention is possible both on the branch and on the body of the jaw. On the jaw branch, a bilateral oblique osteotomy is used according to A. A. Limberg.

Using surgical access at the angle of the lower jaw, the branch is exposed and the masticatory muscles are peeled off. After this, an oblique osteotomy of the jaw ramus is performed from the middle of the notch towards its posterior edge. The jaw is moved to the correct position and its fragments are fastened with a wire suture. From the side of the oral cavity, fixation is supplemented with bent wire splints with intermaxillary traction. Among surgical interventions on the body of the lower jaw, bilateral wedge-shaped resection of the alveolar process with vertical osteotomy according to A. A. Limberg is used. Using a trapezoidal incision, the mucous membrane is dissected in the area of the second small and first and second large molars, the first large molar is removed and at this point the alveolar process is resected in the form of a wedge to the level of the mandibular canal. Next, a vertical osteotomy of the body of the lower jaw is performed through an external incision. After this, the anterior portion of the lower jaw is placed in the correct position and fixed with wire dental splints with intermaxillary traction, as in the case of a bilateral fracture of the body of the lower jaw. Postoperative fixation takes 2 months. At expressed forms In an open bite, only in the area of the incisors and canines, osteotomy of the alveolar process can be used, followed by resection of part of the chin and transplantation of it in the form of a spacer into the defect obtained after moving the alveolar process. In some cases, bilateral decortication of the body of the lower jaw in the area of the intended bend is possible according to the method of A. Ya. Katz. The method is based on weakening the resistance of bone tissue by removing the cortical layer in the area of the removed first large molars. Subsequently, intermaxillary elastic traction is performed (up to 2-2.5 months).

Prognathia. Prognathia is characterized by protrusion of the frontal part of the upper jaw in relation to the normally developed lower jaw. In the most severe cases of prognathia, the frontal teeth of the upper jaw take almost horizontal position. The upper lip is turned up, the lips do not close, the mouth is half open. In patients, mouth breathing predominates. Possible speech impairment (impaired formation of labial sounds).

Some authors associate the occurrence of prognathia with difficulty in nasal breathing, endocrine disorders, and rickets. In some cases, prognathia can be attributed to hereditary diseases. A.I. Evdokimov distinguishes apparent prognathia due to underdevelopment of the lower jaw (false prognathia).

Treatment of prognathia in childhood should be limited to the use of orthodontic equipment. Surgical treatment of prognathia in children is indicated only after unsuccessful orthodontic treatment.

In adults with moderate prognathism, treatment should also begin with the use of orthodontic appliances. With severe prognathia and poor condition frontal teeth are recommended to be removed with partial resection of the alveolar process. Subsequently, the defect in the dentition is replaced with a bridge or removable denture.

If the front teeth need to be preserved, then surgical intervention is performed to weaken the bone of the alveolar process of the upper jaw. To do this, a trapezoidal incision is made on the vestibular and palatal sides, the teeth are removed and a subperiosteal wedge resection of the alveolar walls is performed. extracted teeth. After this, from the palatal and vestibular side in the area of the interalveolar septa of the anterior teeth, a corticotomy is performed with a thin fissure bur (sawing the cortical plate into vertical plane). Mucoperiosteal flaps are placed in their original place and fixed with sutures.

2 weeks after the operation, using orthodontic equipment, they begin to move the anterior part of the alveolar process posteriorly. In cases of severe prognathia with a sharp protrusion of the upper jaw forward, interventions are used, which are based on the bloody mobilization of the entire forward-protruding section of the upper jaw at the level of the first small molars and moving it posteriorly as a single block according to the method of G.I. Semenchenko (Fig. 198).

Fixation of the bone fragment moved to a new position is carried out with a wire dental splint. In some cases, the spongy layer of the upper jaw bone can be left undisturbed and can be limited to only corticotomy followed by the use of orthodontic equipment.

Micrognathia- underdevelopment of the upper jaw, accompanied by retraction of the middle part of the face. At the same time, the upper lip sinks, the lower lip overlaps the upper one. The chin of a normally developed lower jaw protrudes sharply forward and when jaws closed significantly closer to the nose. In the occurrence of this type of deformation, factors such as damage to the upper jaw in early childhood, early operations for congenital clefts of the upper lip and palate, and bad habits (sucking of the upper lip, tongue) are important.

Surgical treatment for macrognathia is indicated only for severe forms in persons over the age of 15-17 years. The essence of the operation is reduced to an osteotomy of the upper jaw slightly above the alveolar process in the direction from the lower edge of the pyriform foramen to the pterygoid process. The mobilized fragment of the upper jaw is moved anteriorly and fixed with dental splints with intermaxillary traction.

To correct micrognathia, prosthetics are often used. For this purpose, the frontal teeth on the upper jaw are removed and the defect is filled with a fixed or removable prosthesis with the dentition moved forward along the prosthesis. This type of intervention can be combined with contour plastic surgery auto- and allogeneic cartilage in the area of the pyriform opening.

In children, upper prognathia accounts for 50-60% of the total number of all deformations of the dentofacial system.

Causes of upper prognathia (excessive development of the upper jaw)

Among the endogenous etiological factors, rickets and respiratory dysfunction (for example, due to hypertrophy of the palatine tonsils) should be mentioned. Among the exogenous ones are finger sucking, artificial feeding using a horn, etc.

Depending on the etiology, the structure of prognathia may be different. Thus, prognathia caused by endogenous factors (for example, impaired nasal breathing) is combined with lateral compression of the upper jaw and close arrangement of teeth in the anterior region. If it is caused by exogenous factors, then there is a significant expansion of the alveolar arch, due to which the teeth in it are located freely, even with intervals (threes), i.e., fan-shaped.

A certain role in the development of maxillary prognathism is played by the incorrect installation of permanent large molars during their eruption. When these teeth erupt, they are installed in a single-tubercular closure: the chewing tubercles of the lower large molars articulate with the same tubercles of the upper ones. Only after the chewing surfaces of the deciduous molars have been worn away and the lower jaw has been shifted medially, the upper first molar with its medial buccal cusp is installed in the intertubercular grooves of the lower ones.

If the physiological wear of the cusps of baby teeth is delayed or does not occur at all, then the first large molars remain in the position in which they erupted. This causes a delay in the development of the lower jaw, which remains in a distal position; upper prognathia develops.

Symptoms of upper prognathia (excessive development of the upper jaw)

It is necessary to distinguish between true prognathia, in which lower jaw has a normal shape and size, and false (apparent) prognathia due to underdevelopment of the lower jaw. With false prognathia, the size and shape of the upper jaw do not deviate from the norm.

The main symptom of excessive development of the upper jaw is its disfiguring protrusion forward; The upper lip is in a forward position and is not able to cover the frontal part of the dentition, which is exposed along with the gum when smiling.

The lower part of the face is lengthened by increasing the distance between the base of the nasal septum and the chin. The nasolabial and mental grooves are smoothed.

The lower lip in the area of the red border is in contact with the palate or back surface frontal upper teeth, the cutting edges of which do not contact the lower teeth at all, even with increased pushing of the lower jaw forward.

The lower front teeth, with their cutting edges, rest against the mucous membrane of the palatal surface of the alveolar process or the anterior part of the hard palate, injuring it.

The upper dental arch is narrowed and extended forward; the palatine vault is high and has a Gothic shape.

Often true upper prognathia is combined with underdevelopment of the lower jaw, which aggravates the disfigurement of the face, especially its profile. The face in this case seems to be sloping downwards (“bird face”).

Treatment of upper prognathia (excessive development of the upper jaw)

Upper prognathism must be treated in childhood through the use of orthodontic appliances. If such treatment was not carried out in a timely manner or turned out to be ineffective, one has to resort to surgical methods.

U adults people with excessively severe prognathia that cannot be treated with equipment, good results provides removal of the anterior teeth and resection of the alveolar process. However, despite the ease of implementation and good cosmetic results, the method cannot be called effective, since the functional power of the masticatory apparatus after such treatment is significantly reduced. Considering that resection of the alveolar process ends with the installation of a fixed bridge prosthesis, which excludes the possibility of further growth of the upper jaw, this operation is permissible only in adults.

Operation by A. Ya. Katz

In this sense, it is more gentle, since it provides for the preservation of teeth: after detachment of the mucoperiosteal flap on the lingual surface of the alveolar process within the upper 6-10 teeth, the palatal part of each interdental space is removed with a bur. The mucoperiosteal flap is placed and sutured in its original place.

Thanks to this intervention, the resistance of the alveolar ridge to the action of the sliding arch, which is installed after surgery, is weakened. The described operation is indicated when the upper teeth are fan-shaped and there are certain spaces between them. Due to these spaces, it is possible to reduce the frontal teeth back and collect them in a close row, achieving contact between the proximal surfaces of their crowns.

Symmetrical extraction of upper premolars

Symmetrical removal of the upper teeth in combination with compactosteotomy is performed in cases where the reposition of all frontal teeth cannot be achieved using the orthodontic method alone, i.e., when each of them is in contact with two adjacent teeth. In addition, it is indicated for prognathism combined with a lateral narrowing of the upper jaw or an open bite. In such cases, one (usually the first) small molar is removed from each side, and then the operation is performed as in the treatment of an open bite.

14 days after compactosteotomy, orthodontic equipment is installed to gradually move the teeth back.

Other treatments for prognathia

Osteotomy and retrotransposition of the frontal part of the upper jaw according to Yu. I. Vernadsky or by P. F. Mazanov is undertaken when it is necessary to quickly (simultaneously) eliminate prognathia, especially in cases of its combination with an open bite, as mentioned above.

Children with increased facial height (skeletal open bite or long face syndrome) usually have a normal upper face and a normal maxilla 25 . This problem has been called vertical maxillary redundancy, but this is not the cause. Before adolescence Most anatomical abnormalities occur below the palatal plane, although some downward and posterior tilting of the maxilla may occur. These children usually have an open bite and almost always some excess eruption of the posterior teeth.

Rice. 15-26. Children with underdevelopment of the lower jaw and an increase in the height of the lower part of the face require treatment with devices that limit the extrusion of the lateral teeth. This stimulates the growth of the mandible in an anterior rather than vertical direction.

Many people experience a decrease in the height of the mandibular ramus, which causes the flatness of the mandibular plane and a large discrepancy between the anterior and posterior facial heights. The ideal treatment option for such patients is to control all subsequent vertical growth so that the mandible rotates upward and forward (Fig. 15-26). Unfortunately, vertical facial growth continues during and after puberty, meaning that even with successful growth modification during the mixed dentition period, active anchorage may be required for several years.

There are several possible approaches to correcting a “long face”. We describe them in order of increasing efficiency.

Rice. 15-27. This figure demonstrates the excellent response to treatment with a high-traction facebow in a child with increased lower facial height. A - profile before treatment. B - profile after treatment.

Rice. 15-27 (continued). C - cephalometric comparison. Comparison of the base of the skull shows that the teeth of the upper and lower jaws do not move downwards; as a result, the lower jaw grows forward, but not downward. The lower jaw shows a forward displacement of the lower molar into the reserve space. The position of the incisors relative to the upper and lower jaws does not change.

Facebow with high traction on molars. One way to correct vertical redundancy problems is to maintain vertical position upper jaw and slower eruption of the upper chewing teeth. This can be achieved with a high-traction facebow, worn 14 hours per day with over 12 ounces of force on each side (Figure 15-27). If the facebow has a conventional facebow on the first molars, then installation and adjustment of the facebow is performed in the same manner as these procedures described for the facebow for the correction of Class II problems 26 27 .

Rice. 15-28. A and B - to distribute the force acting upward and posteriorly on the entire upper jaw, a maxillary splint is attached to the intraoral part of the face bow. The splint better limits tooth extrusion.

Facebow with high traction on the maxillary splint. A more effective way to use extraoral traction in children with vertical overgrowth is to add an anterior plate to the internal arch or use an occlusal splint (see Fig. 15-28) attached to the facebow 28 . This allows vertical force to be directed to all of the upper teeth, not just the molars. This type of appliance is especially effective in children with excessive vertical development of the entire upper jaw and protrusion of the upper incisors (i.e., in children with a “long face” and without an open bite). To ensure skeletal and dentoalveolar correction, the patient must be prepared for the fact that the treatment period can be very long.

Unfortunately, the facebow allows the teeth of the lower jaw to erupt freely, and if this occurs, then changing the direction of growth and beneficial upward and forward rotation of the lower jaw is impossible. Additionally, a facebow alone cannot correct an existing open bite.

Functional device with occlusal pads. Another alternative is to use a functional appliance with occlusal pads (see Fig. 15-29). The retraction force in the functional apparatus has less effect than extraoral traction (the so-called “extraoral traction effect”).

Rice. 15-29. A and B - occlusal pads installed on this functional appliance are used to control vertical growth by limiting the eruption of all lateral teeth. The front teeth erupt freely, which helps close the vertical gap in the frontal area.

The main purpose of the device is to slow down the eruption of lateral teeth and the vertical descent of the upper jaw. This device may provide for placing the lower jaw forward, depending on the degree of underdevelopment of the lower jaw. It should be remembered that careful assessment of the sagittal skeletal relationship is necessary in the presence of vertical skeletal deviations.

Regardless of whether the mandible has been set forward into a constructive bite, if impact on molar eruption is desired, separation must be created. When the mandible is held in this position by the appliance, stretching of the soft tissues (including but not limited to muscles) is applied through a vertical intrusive force to the posterior teeth. In children with an open bite, the front teeth are allowed to erupt freely, resulting in a shorter open bite, while in less common long face problems without an open bite, all teeth are retained with occlusal veneers. Since there is no compensatory eruption of the lateral teeth, all mandibular growth must be directed anteriorly.

Rice. 15-30. This figure demonstrates good reaction for treatment with a functional appliance designed to control vertical growth using occlusal pads in a child with increased lower facial height. A - profile before treatment. B - profile after treatment. C - cephalometric comparisons. Comparisons show that there was no eruption of lateral teeth and all mandibular growth was directed anteriorly. The height of the face was maintained, and the vertical gap was closed through the eruption of the front teeth. The position of the maxillary and mandibular molars relative to the supporting bone was preserved.

IN short time a functional apparatus of this type can effectively control vertical facial growth and close the vertical gap in the frontal area (Fig. 15-30) 29 .

Rice. 15-31. During treatment with fixed appliances, the eruption of the lateral teeth can be controlled using removable posterior bite blocks that separate the lateral teeth at a distance greater than the vertical resting parameters. This creates an intrusive load on the teeth at the points of contact with the blocks, caused by stretching of the soft tissues. The device is fixed in the facebow tubes using clasps.

Because of the long period of continuous vertical growth, if a functional appliance is used in the first stage of treatment, occlusal pads or other elements will be required to control vertical growth during treatment with functional appliances (Fig. 15-31) and possibly during the retention period. and teething. This is necessary because fixed appliances are not able to provide sufficient control of eruption.

Rice. 15-32. Treatment of severe underdevelopment of the lower jaw with a long face model is currently carried out using a high-traction facebow connected to a functional apparatus with occlusal pads. A and B - face before treatment. C - face bow with attachment to a functional apparatus. D and E - face after treatment.

High-traction facebow on a functional appliance with occlusal pads. Currently, the most preferred approach to growth modification for excessive vertical growth and class II relationships is the combination of a high traction facebow and a functional appliance with occlusal overlays for anterior movement of the mandible and control of tooth eruption 30 . Extraoral traction increases control of maxillary growth and ensures that force is applied to the entire maxilla rather than individually to the permanent first molars. A high-traction facebow improves functional appliance fixation (see Fig. 15-32) and directs force toward the intended center of resistance of the maxilla (see Fig. 15-21, D). The functional apparatus provides the opportunity to stimulate mandibular growth while simultaneously controlling the eruption of lateral and anterior teeth.

Rice. 15-32 (continued). F - cephalometric comparisons. Note the convexity of the face, increased height of the lower part of the face, unclosed lips, and exposure of the upper incisors before treatment begins. Comparisons demonstrate overall growth lower jaw down and forward without increasing the angle of the mandibular plane and good control of the vertical position of the teeth.

Modifications of activators or bionators can be designed using various elements of the functional apparatus to stimulate or minimize active dental changes. When using a combination of head apparatus and activator, it is recommended that torque springs be added to the activator (see Fig. 15-33) to reduce the effect of tilting of the maxillary anterior teeth. The exception among active functional devices in this case are active elements, designed to reduce dental and increase skeletal effects 31 .

Rice. 15-33. Torque springs used with a combination of head and functional appliances are designed to apply torque to the crowns of the incisors and provide corpus movement of the incisors or at least overcome some of the lingual inclination of the incisors that is common with all functional appliances.

Clinical work with the head functional apparatus is a hybrid of the techniques used for each apparatus separately, but with some interesting modifications. Firstly, the technique for taking impressions and registering the constructive bite is no different from the usual technique for a functional appliance. The facebow tubes are installed in the bite blocks in the premolar area (see Fig. 15-34). During installation of a functional appliance, a head cap is made for the patient and a small, if not the smallest, face blower is adjusted to be inserted into the tubes. It is usually necessary to close the adjustment loops to ensure that the archwire is not installed too forward.

The combination of facebow and functional appliance is placed in the mouth and adjusted so that the resulting force passes through the intended center of resistance of the maxilla. Passive placement of the inner bow between the lips usually requires a short to medium length outer bow that curves upward. The head cap is connected to the face bow and the force is adjusted to approximately 400 g per each side. After connecting the facebow, additional adjustments to its position may be required.

Rice. 15-34. The functional appliance may have facebow tubes installed to allow additional distal and vertical force to be applied through the facebow and headcap.

As with the installation of any other devices, the patient must be able to handle this device after the first visit to the doctor. The child receives instructions on attaching the facebow, placing the facebow and functional appliance combination in the mouth, and attaching the head cap. If retraction of the anterior teeth is necessary, the adjustment of the retraction springs should be small, if the device is not equipped with clasps, otherwise the fixation of the device will be impaired.

It is usually best for the child to gradually increase the time he or she wears the functional appliance. Use of the head unit during sleep can be started immediately, and then gradually added to daytime use.

The most common are congenital clefts of the jaw, which are the result of a violation of the formation of the face on early stages embryogenesis. Isolated clefts of the alveolar ridge alone are rare. A cleft of the alveolar process of the maxilla is usually combined with a cleft of the upper lip and palate. Median cleft of the mandible and lower lip is extremely rare. Treatment of congenital clefts is surgical. Cleft palates are repaired using plastic surgery, one of the stages of which is fissurorrhaphy - suturing the edges of clefts.

Impaired development and growth of the jaws is primarily associated with damage to bone growth zones in children - trauma (including birth), inflammatory processes(osteomyelitis, arthritis, purulent otitis media), the presence of deep scars in the tissues surrounding the jaws, after burns, nomas, as well as as a result of radiation damage during the period of jaw growth.

Rice. 5. Anomalies in the development of the jaws: a - excessive development of the upper jaw (prognathia); b - underdevelopment of the upper jaw (micrognathia); c - excessive development of the lower jaw (progeny); d - underdevelopment of the lower jaw (microgenia); d - uneven development of the lower jaw; e - open bite.

Underdevelopment of the lower jaw (microgenia) can be symmetrical (with uniform underdevelopment of both sides of the jaw; Fig. 5, d) and one-sided, or asymmetrical. The latter are more common. With symmetrical (bilateral) microgenia, the lower third of the face is reduced, the chin is shifted posteriorly. With unilateral microgenia, the chin is displaced from the midline of the face towards the jaw lesion, the other side looks flattened and as if sinking (Fig. 5, e). Microgenia is most often associated with previous osteomyelitis, ankylosis temporomandibular joint, trauma with damage to the growth zones of the jaw bones.

Excessive development of the lower jaw (Fig. 5, c; macrogeny, or progeny) is characterized by a massively developed jaw with a sharply shifted forward chin. This type of jaw development anomaly is associated with heredity, as it is often observed in several generations of the same family. At the same time, the upper jaw is of normal size.

Excessive development (protrusion forward) of the frontal part of the upper jaw with a normal value of the lower jaw - prognathia (Fig. 5, a).

Underdevelopment of the upper jaw - micrognathia (opistognathia; Fig. 5, b) - is associated with growth disturbances (trauma, early surgery regarding cleft palate).

Open bite (Fig. 5, f) is a deformation in which, when the jaws are closed, only the molars are in contact, and a gap remains between the remaining teeth. It is observed after suffering from rickets, with improperly healed fractures of the jaws, after surgery for ankylosis of the temporomandibular joint.

Treatment of abnormalities of the jaws and dentition is mainly orthodontic (see. Orthodontic methods treatment).

Surgical treatment is carried out at the age of 15-17 years, when the formation of the facial skeleton is largely completed.

Plastic surgeries used to eliminate developmental anomalies and deformations of the jaws can be conditionally divided into two main groups: osteoplastic surgeries and contour plastic surgery. Depending on the type of developmental anomalies and deformations of the jaws, various methods of osteoplastic surgery are shown (Fig. 6). In some cases, the operation consists only of osteotomy of the body or branch of the jaw with subsequent displacement of a fragment of the jaw without the use of a free bone graft, in others - in osteotomy using a free bone graft. As a rule, along with surgery, orthodontic devices are also used to fix the jaws, as well as to correct the bite.

Contour plastic surgery is indicated for moderate jaw underdevelopment and deformation, if there is no significant malocclusion. The operation consists of changing the external contour of the jaw and moving the soft tissues into the correct position. The most effective method is to place a simulated plastic implant under the periosteum.

Rice. 6. Surgical treatment of jaw deformities: a - moving back the frontal part of the upper jaw; b - osteotomy with wedge-shaped resection of the body of the lower jaw; c - osteotomy with wedge-shaped resection of the lower jaw branch; d - closed osteotomy of the lower jaw branch according to Kostechka; d - horizontal or oblique osteotomy of the lower jaw branch; e - vertical osteotomy with wedge-shaped resection of the lower jaw branch; g - osteotomy of the body of the lower jaw with bone transplantation; h - stepped osteotomy of the lower jaw branch; and implantation of plastic in the area of the receding chin.

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BITE ANOMALIES

Prognathia (distal occlusion).

Refers to sagittal malocclusion and is characterized by a discrepancy between the upper and lower jaws in the sagittal direction. The degree of sagittal displacement is determined by the orbital (frontal) plane. Prognathia is a fairly common anomaly that occurs during the period of primary, mixed and permanent dentition. The causes of prognathia are intrauterine and non-humoral factors, disruption of the functional balance of muscles, artificial feeding, early childhood diseases. childhood(especially rickets), inflammatory processes of the jaws, impaired nasal breathing, bad habits, early removal of baby teeth. Prognathia can be caused by excessive development of the upper jaw or upper dental and alveolar arches, underdevelopment of the lower jaw or lower dental arch, distal position or displacement of the entire lower jaw with its dentition with an overdeveloped upper jaw. The relationship of the lateral teeth in the sagittal direction is characterized by the fact that the medial-buccal cusp of the upper jaw closes with the lower one of the same name or lies in the gap between the second premolar and the anterior-buccal cusp of the first molar. Exist various shapes prognathia. As an independent prognathia, it is rare. Most often, it is combined with anomalies in the position of individual teeth, an open or deep bite, and narrowing of the jaws, which in turn aggravate prognathism. Characteristic signs. First form – prognathia has a discrepancy between the upper and lower dental rows in the sagittal direction, which is expressed by different distances between the palatal surface of the upper incisors and the labial surface of the lower ones. The upper front teeth protrude forward in a fan-shaped manner. In one case, the lower incisors move upward and injure the mucous membrane of the palate (deep traumatic bite), in the other, they deviate outward, but space appears between the upper and lower incisors. There is also a narrowing, compression or curvature of the dental arches, and a distal position of the lower jaw. The first form of prognathia also includes a narrowing of the upper jaw or dentition with vestibular deviation of the anterior teeth, often together with the alveolar process. With this form, characteristic facial changes are observed - a shortened upper lip, usually protrudes forward, teeth are visible from under it, which sometimes rest on the lower lip, leaving an imprint on it. The lips do not close, and the lower jaw is pushed back. In the presence of a deep bite, the chin fold is strengthened. A tense facial expression and smoothness of its contours are observed when prognathia is combined with an open bite. Functional disorders are expressed in difficulty biting and chewing food, impaired breathing and speech functions. Second form - with this form of prognathia, the dental arches are flattened in the anterior area. The upper front teeth, together with the alveolar process, are inclined orally and their cutting edges damage the mucous membrane of the gums near the necks of the lower teeth. The alveolar process is often well defined, and the apical base is also sufficiently developed. Sometimes not all the upper front teeth, but only some of them, for example, the central incisors, are inclined towards the palatal side, while the lateral ones are deviated vestibularly, even with rotation along the axis. The lower jaw and lower dentition are usually narrowed, the teeth are closely spaced. The lower incisors are most often in a supraocclusion position and touch the mucous membrane of the palate, on which imprints of their cutting edges are often visible. There is weak development of the alveolar processes in the lateral areas of both jaws. With this form, a dental or skeletal type can also be observed distal occlusion. The second form of prognathia is always combined with a deep bite. It is also called deep interlocking or overbite. Dysfunction is expressed in difficulty in sagittal and transversal movements of the lower jaw. Hinge movements predominate. With unilateral and bilateral gingivocclusion, chewing function is severely impaired, and speech is sometimes unclear. In the second form of prognathia, there is a violation appearance, the upper lip protrudes forward, the lower lip is turned out and pushed back, the chin fold is pronounced. This gives the impression that the lower part of the face is shortened. Shortening or reduction of the lower jaw of the face is observed with significant loss of teeth or with pathological abrasion their. Progenia (medial occlusion). Refers to sagittal anomalies and is characterized by a medial (anterior) location of the lower jaw. The reasons causing this anomaly are illnesses of the mother during pregnancy, underdevelopment of the premaxillary bone, atypical position of the teeth, diseases of early childhood (rickets, etc.), dysfunction endocrine glands, impaired nasal breathing, macroglossia, bad habits, osteomyelitis of the upper jaw, clefts of the hard and soft palate. The cause of progeny, especially true progeny, is heredity. Upon examination, a violation of the facial configuration is noted, which is especially noticeable in the profile: the upper lip and middle part faces are sunken, the chin and lower lip protrude forward, the angle of the lower jaw is turned out, the dentition of the lower jaw is shifted forward compared to the dentition of the upper jaw, and the lower front teeth overlap the upper ones. While maintaining contact between them, the frontal overlap can be normal or deep. If there is no contact, then a gap is identified in the area of the front teeth. In the lateral areas, a violation of the relationship of the molars is most often observed; the medial-buccal cusp of the first permanent molar of the upper jaw is located behind the intercuspal groove of the first permanent molar of the upper jaw (third class according to Engle). The relationship of the lateral teeth in the transversal direction may be normal. With pronounced progeny, a reverse (cross) relationship of the dentition is observed. Progeny is often combined with underdevelopment and narrowing of the upper jaw, excessive development of the lower jaw, abnormal position of individual teeth, deep or open bite, as well as displacement of the lower jaw to the side. There are 2 main forms of progeny - true and false. True progeny occurs due to excessive development of the lower jaw. At the same time, the chin and lower lip sharply protrude forward. There is a pronounced transverse fold above the upper lip under the nose, and a recession of the middle part of the face and upper lip is noted. In most cases, this form of progeny is characterized by a long body of the lower jaw, deployment of its angle (from 120 0 to 140 0 or more), and the ascending branches can be lengthened or shortened. The upper jaw can be of normal size or underdeveloped or narrowed. However, in all cases, the upper dental arch is smaller than the lower one, and the teeth of the lower jaw are usually inclined forward. In the anterior section are found various options reverse overlap: from deep with the presence of contacts, to open bite, with varying degrees sagittal discrepancy between the front teeth. There is a so-called physiological true progeny, which is characterized by multiple contacts in the area of both lateral and anterior teeth. This form of progeny cannot be treated. False progeny develops as a result of a disturbance (delay) in the growth of the entire upper jaw or only its anterior section in the presence of a normal upper jaw. This is facilitated by early removal of baby teeth or edentia of permanent teeth, trauma, and atypical position of the lower jaw. Progenia can also occur due to the displacement of the entire jaw (lower) forward. With progenia, functional disorders boil down mainly to difficulty biting off food and chewing it. Hinge movements of the lower jaw predominate. Disruption of normal articulation can contribute to the occurrence of arthropathy. With progenia, there is also a dysfunction of breathing, swallowing and pronunciation, and speech sounds. Crossbite. At crossbite The buccal cusps of the upper lateral teeth fit into the longitudinal grooves of the lower ones or slip past them from the lingual side. The inverse relationship between the upper and lower dentition most often begins from the canines, sometimes from the incisors. There are unilateral and bilateral crossbites. The following forms are distinguished. First form– buccal or crossbite: - without displacement of the lower jaw to the side; - unilateral, caused by unilateral narrowing of the upper jaw or expansion of the lower jaw, or a combination of these signs; with a displacement of the lower jaw to the side: - parallel to the midsagittal plane; - diagonally. Second form– lingual crossbite: - one-sided, caused by an unevenly expanded upper dentition or an unevenly narrowed lower one, or a combination of these signs; - bilateral, excessively wide upper jaw or sharply narrowed lower jaw, or a combination of these signs. Third form - mixed buccal-lingual: crossbite, caused by a combination of characteristics of the varieties of buccal and lingual crossbite. The following factors can contribute to the occurrence of crossbite: heredity, incorrect position during sleep (placing a hand, fist or pillow under the cheek), bad habits, impaired nasal breathing, atypical position of the buds of individual teeth, diseases of early childhood (rickets), violation of the sequence of eruption teeth, their incorrect articulation, trauma, osteomyelitis, inflammatory processes in the temporomandibular joint. Caused by a discrepancy between the width and lower dentition in the transversal direction. In all forms of crossbite, chewing function is significantly impaired. With a lingual crossbite, the possibility of lateral movements of the lower jaw is excluded. Speech impairment is also noted. With a buccal crossbite with a displacement of the lower jaw in the direction of the disorder, the function of the TMJ is normal, which in the future can cause their disease in the form of deforming arthrosis. Deep frontal (incisal) overlap. The overlap of the lower anterior teeth by the upper ones by more than 1/3 of the height of the crowns, while maintaining the incisal-tubercle contact, is called deep incisal overlap. Deep overlap is observed in the primary, mixed and permanent dentition with a neutral relationship of the dentition, as well as with prognathism or progeny. It may be caused by underdevelopment and narrowing of the lower jaw, its distal displacement or close position of the lower front teeth. With deep incisal overjet without its combination with other malocclusions, no significant aesthetic or functional disorders and treatment in permanent dentition is not always carried out. At correct ratio jaws and intact teeth, treatment is not necessary, except for the combination of deep overlap with TMJ disease. After the loss of one or more lateral teeth in the lower jaw, prosthetics are necessary to prevent a deep bite. If a deep overlap is observed against the background of prognathia, then it is necessary complex therapy main deformation. Deep incisal overlap should be eliminated even in the primary and mixed dentition in order to prevent its further consolidation and the possibility of transition to a deep dentition. Deep bite. A deep bite is a relationship of dentition in the anterior section when the upper incisors overlap the lower incisors by more than 1/3 of the height of their crowns, in the absence of cutting-tubercle contact. The cutting edges of the lower incisors in a state of central occlusion slide past the dental cusps of the upper anterior teeth and come into contact with their palatal surfaces at the necks. In more severe cases, the lower front teeth, with their cutting edges, touch the mucous membrane of the hard palate, leaving imprints on it (deep traumatic bite). At the same time, in the anterior area there is a discrepancy of varying magnitude between the upper and lower dental rows in the sagittal direction. The etiology and pathogenesis of deep bite has been little studied. The occlusal curve of the lower dentition has an atypical shape in the area of the lateral teeth; it is low and sharply curved upward in the area of the anterior teeth. The lower jaw is sometimes narrowed, the teeth may be closely spaced. Refers to vertical anomalies. Open bite. It is observed in primary, mixed, and permanent dentition. It can act as an independent form of anomaly and as a symptom complicating other malocclusion deformities, in particular prognathia and progeny. The causes are heredity, maternal illnesses during pregnancy, active position of tooth buds, diseases of early childhood (especially rickets), dysfunction of the endocrine glands , mineral metabolism, nasal breathing, function and size of the tongue, incorrect position of the child during sleep, bad habits. In the etiology and pathogenesis of open bite, much attention is paid to rickets and the deforming effect of the masticatory muscles on the pathologically altered bone tissue. In this case, the lower jaw bends upward at the location of the molars due to the action of the muscles that lift the jaw. In the area of the chin, it bends downwards due to the traction of the muscles that lower the lower jaw. In this case, the upper jaw can be compressed in the lateral areas and pulled forward. Impaired swallowing is also involved in the development of an open bite, the teeth are open and the tip of the tongue is pushed away from the lips and cheeks. This leads to excessive contraction of the lower lip, chin and other facial muscles. When examined, there is a gap of up to 1 cm or more between the front teeth. In some cases, the gap is a consequence of underdevelopment of the upper jaw in the area of the premaxillary bone, in others it is a consequence of severe deformation of the lower jaw. It refers to a vertical anomaly, but can manifest itself in both the vertical and horizontal directions.

SITUATIONAL TASKS

upper teeth

lower teeth

right side

LITERATURE

Lecture material. Abalmasov N.G., Abolmasov N.N., Bychkov V.A., Al-Hakim A. Orthopedic dentistry. Smolensk, - 2003 Kopeikin V.N. Orthopedic dentistry M., - 1998. Kurlyandsky V.Yu. Orthopedic dentistry. M. – 1977, - 62-64 Additional:

Methodical recommendation

LESSON 7

Topic: Methods for examining orthodontic patients. Diagnosis, plan and tasks of orthodontic treatment. Purpose of the lesson: teach students how to examine orthodontic patients and be able to make a diagnosis. Questions studied previously and necessary for the lesson 1. Age-related morphology of the dentofacial system. 2.Bite, characteristics (physiological and pathological bite). 3.Examination of the patient in the clinic orthopedic dentistry. Questions for control baseline knowledge 1. Clinical examination of orthodontic patients (survey, examination). 2. Special methods for studying orthodontic patients: a) study of diagnostic models; b) X-ray examination teeth, jaws and TMJ; c) cephalometric methods for studying patients. 3.Research functional state dentofacial system. 4. Making a diagnosis, determining the plan and objectives of orthodontic treatment of patients.