Macrogeny

Macrogenia is one of the most severe deformities of the face, ranging from 1.5 to 4.28% of all malocclusion anomalies.

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Symptoms of Macrogensia

Depending on the severity of the sagittal, vertical and transversal discrepancies in the dental arches with excessive symmetrical bilateral development of the lower jaw (progeny), VA Bogatsky distinguishes three degrees of this deformation:

• I degree: the bite is not divided or divided slightly - up to 2 mm: the mandibular angles are unfolded to 135 ° (instead of 127 ° in the norm); the sagittal ratio between the sixth teeth of the upper and lower jaws is broken by no more than 5 mm, only the individual teeth are anomalously located; outwardly noticeably the distance of the lower third of the face and the increase in the chin.
• II degree: sagittal gap between incisors up to 1 cm; sagittal violation of the ratio between canine antagonists and sixth antagonist teeth reaches 1 cm; mandibular angles unfolded to 138 °; abnormally located individual teeth or groups of teeth; in some cases there is a narrowing of the upper jaw, open or deep bite of 1, 2 or 3 degrees. Loss of chewing efficiency is from 68% (in the absence of a combination of prognosis with an open bite) to 76% (when combined with an open bite).
• III degree: sagittal fissure in the frontal region more than 1 cm; sagittal violation of the ratio between the first molar antagonists reaches 1.1-1.8 cm; mandibular angles unfolded to 145 °; teeth are abnormally located; there is an open or deep (back) bite; loss of chewing efficiency is 72.5% when combined with an open bite, and 87.5% when combined with a deep bite.

Unlike other classifications of predictions, Bogatsky's classification reflects sagittal, transversal and vertical discrepancies in dental arches, which is very important to consider when planning an operation.

When combined deformations of the jaws by the type of prognosis, the curvature of the nasal septum, chronic rhinitis, deterioration of the nasal cavity for air flow are noted.

Changes from the external ear are mainly due to deformation of the external auditory canal (caused by excessive development of the head of the lower jaw); impaired patency of the auditory tube (due to frequent rhinitis and diseases of the nasal part of the pharynx); adhesive and chronic purulent otites, disturbances in sound production (within 10-15 db) are also noted.

Spirographic studies by IM Migovich (1998) show that most patients with prognosis with open bite have pulmonary ventilation, which obliges the surgeon to carry out before the operation a thorough examination and sanitation of the patient's airways.

A special local examination should begin with the manufacture of a face gypsum mask, photograph the patient in three projections, take a cast (algalastom or stomalgin) and make two or three pairs of models of jaws and dentition along them.

Models are needed in order to clarify the size and shape of the dentition, their relationship, the nature of secondary deformations of the upper jaw. The models develop a plan for the forthcoming operation, the method of the most rigid fixation of jaw fragments after osteotomy. One of the pairs of models is fixed in the wire articulator so that it can "maneuver" the sawn fragments of the jaw, imitating their location after osteotomy. For this purpose, a site corresponding to the upcoming osteoectomy is cut into the model.

Teleradiography can provide the most complete picture of the nature of the anomaly and the localization of the most deformed parts of the bones of the face, and also determine which part of the bone (lower, upper jaw) causes deformation and which fragment should be removed or moved in order to obtain a normal profile and correct occlusion. In addition, this method of radiography documents the profile ratio of soft tissues and bones of the face, which is important in the subsequent evaluation of the result of the operation.

Treatment of macrogensia

The treatment of mandible prognathion by surgery is a difficult task, since there are no sufficiently clear standard criteria that could be relied on when choosing a method of treatment. Therefore only thoughtful preoperative preparation of the patient provides a sufficient effect of the operation.

In occasion of age indications to carrying out of surgical intervention at proge-nii opinions of surgeons differ a little. Some consider it possible to implement it at any age; according to others, operations are possible only from the age of 13 years.

We believe that if, with a significant underdevelopment of the lower jaw, surgical intervention should be performed as early as possible, then with moderately pronounced prognosis (I degree), the operation can be delayed up to 13-15 years, that is, until the growth of the bones of the face. The less pronounced the degree of progenic deformation, the later it is possible to perform the operation. When the same grade II-III progeny is performed, the operation should be performed until the specified age.

Moderately expressed prognosis (I degree) usually does not entail a significant deformation of the upper jaw. Therefore, in such cases, there is no need to rush into the early operation.

Exodus of surgical treatment of progeny

When assessing the outcome of treatment, it is necessary to take into account not only the ratio of the jaws, but also the height of the lower third of the face, the shape of the corners of the lower jaw, as well as the chin and middle parts of the face.

To achieve the necessary proportions of the face it is possible only if the patient, in addition to the main operation (on the body and the jaw branch), will also have additional corrective operations (contour plasty, resection of the mandible body in the chin or jaw angles, etc.). .

Recurrence of progrenia can result from insufficient contact between jaw fragments, changes in the thrust direction of the masticatory muscles, or as a result of macroglossia.

According to available data, insufficient adaptation of the bony surfaces of the jaw branch can lead to an open bite and cause an early relapse - immediately after the removal of the intermaxillary fixation.

In view of the fragility of the young bone callus, the thrust of the masticatory muscles leads to the displacement of bone fragments. This is more often observed after operations performed on the branch "blindly" and in the horizontal direction; in particular after the operation Kosteeka the upper fragment can move forward and upward (under the action of the temporal muscle) and lose contact with the lower fragment.

Since macroglossia contributes to the occurrence of relapses of prognosis, an open bite or a false joint in the place of the osteotomy of the jaw, some authors recommend reducing the tongue (resecting part of it simultaneously with the implementation of osteoectomy in the area of the jaw).

The lack of effectiveness of the operation in the cosmetic sense is due to the fact that after it an excess amount of tissue is created on the face, going to the "accordion" as a result of the reduction of the lower jaw. This is especially pronounced in the full elderly patients.

Damage to one of the branches of the facial nerve can occur if the surgeon did not pierce the skin and the scalpel that was to be fed before insertion of the Kerger needle and inserted a narrow metal tool (spatula) into the formed wound channel to protect the facial nerve branch. Unfortunately, this complication is often irreversible, in spite of the physiotherapeutic and medicinal treatment being used. In the case of the development of persistent paralysis of this or that group of facial muscles, a corresponding corrective operation should be undertaken.

To prevent this complication, it is advisable to perform operations through intraoral access, especially with interventions on the proximal jaw areas.

When performing operations through extraoral access, it should be remembered that the mandibular angle during the prognosis is always slightly higher than normal, and therefore the incision of the skin in the submandibular region should also be located somewhat lower than in the usual opening of phlegmon or other operations. Damage to the parotid salivary gland followed by the formation of a salivary fistula from one or both sides after surgery by Kosteeka occurs, according to the literature, in about 18% of patients. However, in each case, fistulas disappear on their own.