Occlusion - contact when closing teeth. Orthodontist deals with such problems. Orthodontics of mesial occlusion includes all sections of this phenomenon - from etiology to treatment and prevention.
Overbite is an abnormal occlusion in which the row of teeth on the mandible overlaps the teeth of the upper row during jaw closure. Then a characteristic step is formed. Pathology is observed in 11.8% of patients. It is considered a complex dentoalveolar curvature. The opposite of it is the distal bite, where everything is exactly the opposite.
General information
Mesial occlusion can also be combined with other malocclusions - vertical and transversal (cross), with transposition of individual teeth, accompanied by an open bite. In dentistry, mesial occlusion is called "progenia", "anterial occlusion", lower prognathia. Most often, it turns out to be underdeveloped upper jaw or toodeveloped bottom.
The term "mesial occlusion" was introduced into orthodontics in 1926 by Lischer. And back in 1899, E. Engle created a classification of dentoalveolar pathologies, where he attributed progeny to class III anomalies, which means the location of the first chewing teeth (molars) in front of the upper ones when closing.
For centuries, people with such problems in the form of a bulky lower jaw were classified as feeble-minded, but among them were outstanding personalities - Emperor Charles V and the great composer Richard Wagner. Photos of mesial occlusion will be presented below.
Causes of the anomaly
Mesial occlusion is polyetiological - it can be caused by genetic disorders, congenital and acquired factors. Genetic types of progeny occupy 20-40% of all cases and are associated with those features of the facial bones of the skull that are passed down through generations.
In the prenatal period, diseases of the pregnant woman, traumas and pathologies of childbirth, jaw hypoplasia, etc. become the cause of violations. The provocative factors can be the teeth of the lower jaw in excess, adentia of varying degrees in the upper jaw (absence of teeth), microdentia of the upper teeth, shortening of the frenulum of the tongue or its large size.
Causes of mesial occlusion of the dentition can also be:
- childhood rickets;
- artificial feeding;
- wrong position of the child in a dream (lowering the head to the chest);
- supporting the chin with a fist while sitting;
- osteomyelitis of the upper jaw;
- ENT diseases (chronic tonsillitis, deviated nasalpartitions);
- early change of milk teeth of the upper jaw;
- uneven wear of children's teeth (canines);
- delayed growth of permanent teeth.
If the milk fangs are not worn out over time, this will also contribute to the extension of the mandibular part of the skull to the front position. In this position, she remains stable. Bad habits such as sucking a finger, tongue, upper lip, and a constant nipple in the mouth have a very negative effect on the appearance of progeny.
Classification
There are 3 forms of mesial occlusion. They will be discussed below. So, the classification of pathology:
- True mesial occlusion, or open, is a genetic pathology and occurs in representatives of the same genus, becoming their hallmark. Incorrect bite is diagnosed already in the first year of life. The provoking gene occurs in offspring in 30% of cases. Often a cold of a pregnant woman in the first trimester becomes a contributing moment.
- False, or closed progeny - the provoking factor is the prolonged stay of the lower jaw in the extended state for various reasons: inflammation of the nasopharynx, when breathing is carried out mainly through the mouth. A short frenulum of the tongue (uncut) can also be a cause. The anomaly becomes noticeable when the teeth are closed. Diagnosis becomes possible after 12 years. Visually, it may not be noticeable.
- Combined forms of mesial occlusion - a combination of the 2 previous options. This form is the worst diagnosed and treated.
Subject tomalocclusion in the sagittal plane and the angle of the lower jaw in the classification of mesial occlusion, there are 3 degrees of pathology according to Angle:
- First degree - sagittal gap between the incisors of the jaws from 3 mm, but not more than 5 mm, mandibular angle up to 131°.
- Second degree – sagittal fissure up to 10 mm, mandibular angle up to 133°.
- Third degree - sagittal fissure more than 10 mm - 11-18 mm, mandibular angle up to 145°.
What is the sagittal fissure? This is the distance from the front teeth of the upper jaw to the front teeth of the lower jaw. By the way, with a sagittal fissure of more than 10 mm, a young man may be considered conditionally fit when drafted into the army. This systematization was created back in 1898 and has flaws.
Engl takes into account here the displacement of the teeth only in the sagittal direction, but the displacement practically occurs in three mutually perpendicular directions. Therefore, today such a classification has only a historical aspect, although in some places it is used abroad.
There are 3 types of underbite: open, deep and cross.
Shapes
There are 3 types of mesial bite:
- First form - no sharp difference in jaw development, mandible central incisors overlap upper teeth.
- The second form - the lower teeth already reach the mucous membrane of the upper lip. The lower jaw is more developed and massive than the upper, but not by much.
- Third form - in this version, the upper jaw is smaller thanlower. The front teeth do not touch. The tongue presses hard on the upper teeth.
There are also dentoalveolar and gnathic clinical forms of mesial occlusion. In the first case, the lower jaw can arbitrarily move to the correct bite of the chewing teeth. The gnathic form does not allow displacement.
Symptomatic manifestations
Mesial occlusion corresponds to the closure of the molars according to the 3rd Angle class - this is a sagittal malocclusion. At the same time, the mesial displacement of the crowns of the first chewing teeth by 0.5 of the width of the tubercle or more is the main diagnostic sign.
Mesial occlusion clinic in external manifestation is expressed in a massive protruding chin (masculine), the profile of the middle part of the face becomes concave to varying degrees, the upper lip sinks, and the lower lip protrudes.
Face becomes angry. Such a face in men is often considered even attractive and masculine, but for a woman this characteristic is the opposite in meaning.
The upper lip appears smaller and shorter than the lower lip, and the part of the face below the nose also appears unnaturally short.
Mesial occlusion is also characterized by the presence of functional changes - speech and chewing are disturbed.
Speech becomes lispy or burr, diction is slurred. Biting and chewing food becomes problematic. The nasolabial folds become clearly defined, deep, the nose is elongated, the size of the tongue is increased. When chewing, there may be a crunch, lateral movements of the jaw inpatients are difficult.
Diagnosis of progeny
For the diagnosis of mesial occlusion, it is necessary to consult an orthodontist - a specialist in the correction of jaw pathologies. He will not only conduct a visual examination and take anthropometry to assess the pathology, but also conduct functional tests to separate the true and false forms. For this purpose, bite wax rollers, tomography, radiography, orthopantomography are used. As an additional diagnosis, myography of masticatory and temporal muscles can be performed.
Diagnostic jaw models
The Gerlach method will reveal the ratio of the segments using a special formula, which is important for choosing a treatment with the removal of individual teeth in the lower jaw.
Pohn's method - violation of the transversal dimensions of the dental arches in the mesial occlusion and clarification of their localization.
The Korkhouse method establishes that the length of the anterior dental arch of the upper jaw is reduced compared to the lower jaw.
In order to choose treatment for mesial occlusion, it is sometimes necessary to establish the degree of ossification of the general skeleton and its facial part on the x-ray. This is also important for predicting treatment outcomes. The patient's hand according to Burke is being studied for this.
Lateral head x-ray is the most informative and often the main method for diagnosing malocclusion.
The degree of severity of the pathology is assessed by bites of the bite ridges, teleroentgenography (TRG) in the lateral projection is an x-ray that captures the entire skull.
Complications of the anomaly
Mesial occlusion is dangerous with the following complications:
- migraine;
- dizziness;
- ringing in the ears;
- Enamel wears off early in the upper row of teeth, because the load on them is increased;
- thinning of the bones of the skull;
- indigestion with irritation of the stomach because the food is not chewed well;
- diseases of the jaw joints and oral cavity - periodontal disease;
- facial muscle spasms;
- difficulties in oral hygiene;
- loose and decaying teeth;
- tooth loss;
- difficulty placing implants;
- aesthetic problems.
Treatment
Treatment of mesial occlusion is best started at the first sign. The success of therapy depends on the age of the patient, the cause of the anomaly, the degree of neglect and the correct implementation of all recommendations. In addition, treatment for success must be comprehensive:
- surgical intervention to change the structure of the dental system;
- myotherapy for the development of lagging elements of the lower face;
- use of orthodontic appliances - braces, mouthguards, plates, etc.
To begin with, they are determined with the age of the patient. If the growth of the mandible bones is not yet complete, you can try to slow down this process. Otherwise, they try to reduce its size.
Treatment of progeny in young patients
Orthodontic devices are used for therapy - helmets withwith a chin sling attached to it with a rubber band, masks and Frenkel's clasp activators.
In the early stages, it is recommended to wear interchangeable devices, including dental trainers and mouth guards (tires).
Trainers are used more often because they act on the muscles, training them. That is, the cause of the defect is being eliminated. The bite in such cases is aligned more effectively.
Treatment of mesial occlusion in milk bite (temporary) is to provide an optimum for the growth of the alveolar process of the maxillary bone. If the cause is a shortened frenulum of the tongue, cutting it can make it normal (plasty).
Trying to restore normal chewing and swallowing. For this, hard food is recommended, with a bad habit of sucking everything, standard or individual vestibular plates are used. They are elastic, hypoallergenic, made of silicone and perfectly switch the baby's attention. It is placed in the oral cavity, it does not put pressure on the upper jaw, which occurs when sucking objects in the mouth.
The circular muscle of the mouth is trained with myogymnastics so that the lips begin to close properly and the child breathes through the nose.
Exercises of the circular muscle of the mouth are done using the Dass activator. Also, the cutting edges of the upper and lower incisors, tubercles of the canines are often ground with further massage of the alveolar process (this is part of the bone) of the upper jaw.
Massage is done for 2 minutes in the morning and in the evening. It ultimately helps to properly close the incisors on both jaws.
The Brückl apparatus is a corrective orthodontic device,which has a basis with an inclined surface. When worn around the clock for a month, the teeth begin to close completely and correctly, the bite returns to normal.
Treatment of progeny in schoolchildren
In addition to the above devices, a Frenkel regulator or a third type Klammt activator, etc. are used. The Frenkel device is a metal wire frame to which plastic shields are attached. Made individually. The design prevents soft tissue from growing around the maxillary teeth.
If the devices do not work, the method of treatment is the removal of some teeth in the lower jaw - this is in adults (premolars, canines).
The most popular and effective treatment for mesial occlusion is the use of braces. Their cost is from 35 to 300 thousand rubles. Children need to wear them for 1.5 years. Also, a good effect of such treatment was noted in adolescents.
Treatment of mesial occlusion in mixed dentition (mixed dentition - the simultaneous presence of removable and permanent teeth) is carried out by the same methods as for milk teeth.
In addition, the following is often used:
- Double Schwartz plate - well corrects the mesial occlusion. She has a special sliding pin that tends to push the lower jaw forward.
- The use of activators also gives good results. The Andresen-Goipl and Wunderer activator are almost the same - used for milk and mixed dentition with mesial occlusion.
- Screw (pushers) Weise - installed in the areaanterior teeth. The screw is an integral part of the factory-made orthodontic appliance. It can be adjusted by the patient himself. When the screw is unscrewed, the device moves mesially, and its mandibular part distally. With this artificial pressure, the correct movement of the contact occurs.
- Frenkel type 3 regulator - creates and maintains myodynamic balance in the jaws and helps to eliminate morphological disorders of the progeny.
Treatment in permanent dentition
Treatment of mesial occlusion in adults with a conservative method is not always effective. For them, only two options are applicable: braces (kappas) or surgery.
In the period of permanent occlusion, mainly non-removable braces are used. The best effect is achieved with early treatment. Success is manifested in the alignment of the face and the normal position of the chin. The most effective therapy is observed in children under 12 years of age.
It is difficult and long to treat adult patients, as the dentition is already ossified and fully formed, therefore it is extremely difficult to change. The duration of treatment can take from 3 to 5 years. The intervention of the surgeon most effectively helps with progeny.
In adult patients with mesial occlusion with deep incisal overlap of the entire height of the upper crowns of the lower teeth, the prognosis is poor. In these cases, an attempt is made to shorten the lower dental arch by removing some of the teeth in the lower jaw.
After conservative treatment, the results must be fixed, which is called retention. For this purpose, a fixed retainer is used - this is a metal structure in the form of a metal arc, which is attached to the inside of the teeth and maintains the position of the entire dentition.
With severe progeny, only the surgical method of treatment is applicable. It becomes the only effective one.
Operation
Usually, the teeth of the lower row are removed. These operations are quite expensive and often lead to complications (for example, damage to the trigeminal nerve).
With a large size of the lower jaw before the operation, it is advisable to push forward the underdeveloped upper jaw or try to develop it. It always creates he alth problems for its owner. Then the landmark is more accurate for surgeons. This is the work of an orthodontist.
With a good result with the upper jaw, the patient may refuse the operation. In adults, the duration of treatment always increases, they pass in stages.
Myogymnastics
Myogymnastics is used in dentistry not only to eliminate malocclusion, but also to prevent it. The purpose of this gymnastics is to train certain muscles. Gymnastics gives the best result in children 4-7 years old.
How to do gymnastics
To get the effect of gymnastics, you need to follow some rules:
- Speed and repetitions should be increased only gradually.
- Muscles to reduce as much as possible.
- The pause between contractions should be the sameby duration, as with reduction.
- Do gymnastics only to slight fatigue.
Missal bite exercises
With mesial occlusion, special gymnastics also helps, which is performed in the morning and in the evening, literally for 10-15 minutes. Repeat exercises 10 times. Positive results first appear after 3 months, and successful results after six months.
Exercises the dentist can supplement with preventive sawing of the top layer within the enamel to reduce premature contacts. The procedure is called grinding.
In class, you need to have a special vestibular plate with you. Even after gymnastics, they put it in the mouth at night. The goal of the classes is to constantly train the orbicular muscle of the mouth to correct the position of the mandible.
The flap of the record prevents the child from sticking his tongue between his teeth with the desire to suck, for example, a finger. They pull it forward by the ring with the movement of the right hand and try to hold it with their lips.
With the tip of the tongue you need to press on the hard palate of the maxilla until a feeling of slight fatigue appears (3-5 minutes). Tilt your head back slightly, gently opening and closing your mouth. With your mouth closed, you should try to reach the back edge of the hard palate. With a sagging lower lip, pull it under the upper front teeth, then slowly release it.
Prevention of prognathia
Prognathia can be corrected at any age, but the effect will be different. However, a woman needs to anticipate it and carry out prophylaxis already during pregnancy. This is especially important in the firsttrimester, when the most important organs are laid.
Facial bones are formed by 7-15 weeks. It is necessary to competently manage childbirth with an incorrect presentation of the fetus - gluteal, lower or transverse. This will help avoid birth trauma.
A newborn baby is better to breastfeed. Each breastfeed should last at least 20 minutes. Although the baby eats up during the first 5-6 minutes of the time, the rest of the time is spent on training the jaw muscles when sucking. If the breast is taken away, the baby will suck on a finger or a pacifier to improve the sucking reflex.
Watch your baby's manners and eradicate bad habits such as sucking lips, fingers, nipples, toys, etc. Dentists recommend giving a pacifier to a child until the first teeth erupt, then gradually wean the child from it.
It is also important that the child sleeps in the correct position - there should be no high pillow, hunched posture, sleeping on the stomach. Correct posture is important with the exclusion of kyphosis, hardening of the child in order to prevent diseases of the upper respiratory tract, colds with complications.
Gymnastics of the facial muscles for the purpose of prevention is selected by a doctor. With genetic etiology, this is ineffective.
Conclusions
In mesial occlusion of the dentition, the causes are more often skeletal than dental. This usually applies to the upper jaw - it is either small or located behind. In the first case, to correct it, they try to develop it, in the second - to pull it forward.
An attempt to restrain and slow down the growth of the lower jaw has practically no prospects, thisimpossible in adults by physiology.
Surgical treatment of prognathia is carried out in cases where the cause is too large a lower jaw. To identify this, making a proper diagnosis is paramount.
