Anomalies and deformations of the jaws
Last reviewed: 23.04.2024
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The size and shape of the jaws can vary greatly according to the individual size and shape of the entire face. The deformation of one or both jaws can only occur if there is a sharp deviation from the conditional mean values that most correspond to the rest of the face of the individual.
The second criterion for the presence of deformation of the jaw is a violation of chewing function and speech.
Excessive development of the lower jaw is called prognosis or macrogenia, and its underdevelopment is called microgenia or retrognathy.
Excessive development of the upper jaw is called macrognathia or prognathia, and underdevelopment is called micrognathia or opistognathia.
What causes anomalies and deformations of the jaws?
The causes of tooth-maxillofacial deformations are very diverse. Thus, the organo- and morphogenesis of the jaws in the fetus may be affected by the hereditary effect on the embryo, the parents borne diseases (including endocrine and metabolic disorders in the mother's body, infectious diseases ), radioactive irradiation, and also due to physiological and anatomical disorders of the genital organs of the mother and the wrong position of the fetus.
In early childhood, the development of the jaws can be affected by endogenous factors (heredity, endocrine disorders, various infectious diseases, metabolic disorders) and exogenous effects (inflammation in the areas of jaw growth, trauma, including birth, radiation damage, mechanical pressure, harmful habits - sucking a finger, pacifiers, lower lip or putting a cam under the cheek during sleep, pushing the lower jaw forward during the eruption of wisdom teeth, while playing the children's violin and t etc., dysfunction of the masticatory apparatus, violation of the act of swallowing, nasal breathing, etc.).
In childhood and adolescence, as well as in adults, deformations of the jaws can occur under the influence of accidental trauma, coarse Scarring concretions, surgical intervention and pathological processes (osteomyelitis, ankylosis, nome, etc.). The latter can lead to excessive bone regeneration or, conversely, to resorption and its atrophy.
The dystrophic process can lead to half, or two-sided, or limited atrophy of soft tissues and the skeleton of the face (for example, the so-called hemiatrophy).
In the presence of conditions that promote hypertrophy of the bones of the face, there is an acromegaly growth of the bones, especially of the lower jaw.
Quite often, the acquired unilateral underdevelopment of the lower jaw is caused by osteomyelitis, a purulent inflammation of the temporomandibular joint and mechanical damage to the condylar process in the first decade of the patient's life.
Pathogenesis of jaw anomalies and deformations
At the heart of pathogenetic mechanisms of development of jaw deformations lie oppression or partial exclusion of the growth zones of the jaw, loss of bone substance, exclusion of the chewing function or opening of the mouth. In particular, the main factor in the development of unilateral microenias is the disruption of the growth of the mandible in length due to congenital or osteomyelitis lesions or exclusion of the growth zones, especially located in the head of the lower jaw.
A significant role in the pathogenesis of jaw deformations is played by endocrine disorders in a growing organism.
The pathogenesis of the combined deformities of the bones of the face is closely related to the impairment of the function of the synchondrosis of the base of the skull. Micro- and macrognathia are caused either by oppression or irritation of the growth zones, localized in the heads of the mandibular bone.
In the development of prognosis, an important role is played by the pressure of an incorrectly located tongue and a decrease in the volume of the oral cavity.
Symptoms of anomalies and deformities of the jaws
Among the symptoms of jaw deformities, the first place is usually the dissatisfaction of the patient (and often - and the people around him) with the appearance of the face. Especially persistently express this complaint of the girl and the young man: they ask to eliminate the "disfigurement" of their person.
The second symptom is a violation of one or another function of the dento-maxillofacial apparatus (chewing, speech, the ability to sing, play on a wind musical instrument, smile broadly, fun and playfully laugh in the circle of friends, in the family, at work).
Violation of the bite complicates the process of chewing food, forcing it to swallow it hastily, without saliva treatment. Some solid types of food are generally inaccessible. Meals in the dining room, restaurant or cafe is simply impossible, because the appearance of the patients causes disgust at others.
Among the complaints, there may be an indication of the discomfort that appears (in the stomach) after eating, which is due to the acceptance of rough, uneaten food.
Alienation in the family and at work forces the patients to self-isolate against the work collective, the family, generates mental imbalance.
Some (especially those with microenia) complain of very loud snoring (during sleep on their backs): "It's like driving a motorcycle or truck all night" - as one of our patients put it. This excludes the possibility of sharing a dream with his wife (husband) and sometimes serves as a reason for divorce; This, in turn, aggravates the psychoemotional imbalance, and sometimes - and attempts at suicide. In short, the category of patients is very difficult and requires very strict compliance with all ethics rules, a thorough preoperative sedative premedikaiii, thoughtful selection of methods of anesthesia during and after surgery.
When abnormalities and deformations of the jaws, sharp changes in the tooth-jaw system are often observed (tooth decay, tooth decay, enamel hypoplasia, abnormal abrasion, abnormal position of the teeth, changes in periodontal tissue, and malfunction of the masticatory apparatus).
The frequency of the lesion and the clinical picture of their manifestation are different. In particular, the incidence of caries in these patients is observed 2-3 times more often than in patients without malocclusion. The intensity of caries damage with deformation of the upper jaw after cheilo- and uranoplasty (in all age groups) is much higher than when the lower jaw is bent and the bite is open.
Inflammatory-dystrophic changes in periodontitis are noted in most patients. When the lower jaw is bent and the bite is open near the teeth that are not in contact with the antagonists, limited catarrhal gingivitis is revealed.
The structure of the periodontal bone tissue is characterized by chaotic and blurred bone pattern with a predominant lesion of the lower jaw.
For deformations of the upper jaw, abnormal gingival pockets are characteristic, hypertrophic gingivitis of a diffuse nature, more often in the region of the frontal teeth located along the edges of the cleft, and the teeth experiencing the greatest load.
Disturbances of the masticatory function (according to mastyciogram) are manifested by grinding and mixed types of chewing.
Electroexcitability of the pulp of teeth under conditions of overload and underload, as well as in dysfunctional teeth, decreases.
For completeness of drawing up a picture of violations of local status, it is necessary to use also such research methods as linear and angular measurements of the outline of the whole face and its parts; making photographic images (in profile and in full face) and gypsum masks; electromyographic evaluation of masticatory and facial muscles; Radiographic examination of the bones of the face and the cerebral cranium (teleradiography by Schwarz, orthopantography, tomography). All these data allow not only to clarify the diagnosis, but also to choose the most acceptable variant of the operation.
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