Occlusion of teeth is the closure of the lower and upper row of teeth (occlusion). Many dentists argue about the method of determining occlusion and articulation. Some believe that articulation is the contact of each row of teeth with each other at the moment of movement, and occlusion is the same only at the moment of rest. At the same time, articulation and occlusion continue to be the main factors that determine the relationship between the teeth: the load on the muscles, joints and the teeth themselves. With the correct closure of the dentition, a correct bite is formed in a person, which significantly reduces the load on the mandibular joints and teeth. If pathology has developed, then the rapid destruction of the crown, periodontium, as well as a change in the shape of the face begins.
Occlusion detection
It is the occlusion of the teeth that is responsible for their correct position in the oral cavity. Under the condition of normal operation of this system in the oral cavity, the complex work of masticatory muscles, temporomandibular joints and crown surfaces is performed.
Stable occlusion can be achieved with multiple fissure-cusp contacts of the posterior molars. The correct position of the dentition inoral cavity is considered an essential factor, without which the periodontal tissues are quickly damaged and the chewing load is distributed incorrectly.
Signs of illness
Violation of the occlusion of the teeth leads to difficulties with the process of chewing food, which is accompanied by pain, migraine and clicking in the temporomandibular joints.
Due to improper closure, active abrasion and destruction of the dental crown occurs. It is these processes that lead to dental diseases: periodontal disease, gingivitis, stomatitis, loosening, early loss of teeth.
When the occlusion is too strong, the incisors located on the lower jaw begin to injure the mucous membrane in the mouth, as well as the soft palate. A person with this ailment becomes difficult to chew solid food, they have problems with breathing and articulation.
How does it appear on external examination?
Problems with occlusion lead to changes in facial features as well as its overall shape. Depending on the type of violation that has occurred, the chin either decreases in size or moves forward. You can note the characteristic asymmetry of the lower and upper lips.
At visual inspection, you can easily notice the incorrect arrangement of rows of teeth in relation to each other, the presence of diastemas, as well as crowding of the incisors.
At the moment when the jaw is inactive, between the chewing surfaces of the teeth there is a gap of 3 to 4 millimeters, which is otherwise called the interocclusal space. With the developmentpathological process, such a distance begins to decrease, or, conversely, increase, which leads to a malocclusion.
Main types of occlusion
Specialists classify dynamic as well as static form of violation. With dynamic occlusion, special attention is paid to the interaction between the rows of teeth at the moment of jaw movement, with static occlusion - to the nature of the closing of crowns in a compressed state.
In turn, static type occlusion is divided into pathological anterior, central and lateral. Detailed description of the types of occlusion of the teeth:
- Central. With such a violation, the location of the jaws is maximum intertubercular, the upper crowns overlap the lower ones by a third, the lateral molars have a fissure-tubercle contact. When considering external signs, no special changes can be noticed.
- Anterior occlusion. The lower jaw is strongly displaced forward, the incisors form butt, the masticatory teeth do not close, gaps appear between them, similar to a rhombus. When considering external signs, one should note a slight protrusion of the chin and lower lip forward, as well as an “angry” facial expression in a person.
- Lateral occlusion of the teeth is a displacement of the jaw in a certain direction, most of the chewing load falls on only one canine or the chewing surfaces of the molars on the side to which the jaw is displaced. External signs are as follows: the chin is shifted to the side, the midline of the face corresponds to the gap between the front incisors.
- Distal. With this form of violation, there is a strong displacement of the lower jaw forward, and the upper premolars overlap with the lower buccal tubercles. When examining the patient's face, one can distinguish a strongly advanced chin, as well as a "concave" type of face.
- Deep incisal occlusion. In this condition, the incisors of the upper jaw overlap the lower ones by more than 1/3, the patient does not have cutting-tubercular contact. When considering external signs, one can note the small size of the chin, a large lower lip, as well as a strongly prominent nose (in other words, a "bird's" face).
What are the reasons for development?
Tooth occlusion in humans can be either acquired or congenital. The congenital is laid at the stage of development of the child in the womb, while the acquired develops throughout life.
Bite problems in most cases are detected in adolescents at the time of the change of milk teeth to permanent ones.
Bite problems can be affected by the following negative factors:
- predisposition at the genetic level;
- congenital anomalies with the formation of the jaw, birth trauma;
- bad habit of thumb sucking in childhood or too late rejection of a pacifier;
- an increase in the size of the tongue that does not correspond to the norm - macroglossia;
- the timing of teething is very different from the norm;
- destruction of milk molarscaries;
- problems with the formation of the temporomandibular joints;
- development of diseases of the central nervous system;
- irregular nasal breathing, especially at night;
- the beginning of the inflammatory process in the masticatory facial muscles.
Occlusion is also divided into temporary and permanent. At the time of birth, the baby's jaw is in the distal position.
Until the age of three, the child's bone structure grows rapidly, and milk teeth develop according to their anatomical position. It is these processes that are responsible for the formation of a correct bite with a central closure of the dentition.
Carrying out diagnostic measures
The orthodontist and dentist deal with the diagnosis of such a disorder. The specialist conducts a visual examination and determines the severity of the violation of the closure of the dentition, makes a cast of the jaws from the alginate mass.
Further, the finished cast of the jaws undergoes additional checks for the presence of pathology, and the size of the interocclusal gap is also measured. Some patients are additionally prescribed an occlusiogram, orthopantomography, electromyography and teleroentgenography in several projections at once.
After receiving the results of the TRH, a professional evaluates the condition of the bone structures and soft tissues, which helps to determine further actions and develop orthodontic treatment measures.
Determination of central occlusion in case of partial absenceteeth
Diagnosis of central occlusion is very important for prosthetics with partial or complete absence of teeth in the oral cavity. Particular attention during diagnostic measures is paid to the height of the lower part of the face. In case of incomplete adentia, the location of antagonist teeth is taken into account, if there are none, then the mesiodistal ratio of the jaws is determined using wax bases.
Methods for diagnosing central occlusion:
- Functional method for determining central occlusion in partial absence of teeth. During the procedure, the patient throws his head back on the back of the dental chair, and the doctor puts his fingers on the surface of the teeth of the lower row and asks the patient to touch the palate with his tongue and start swallowing. When such movements are made, the involuntary extension of the lower jaw forward, as well as the convergence of the occlusal surfaces.
- The instrumental method for determining central occlusion in case of partial loss of teeth is carried out using a specialized instrument. It helps to accurately determine all movements of the lower jaw.
Complete absence of teeth in occlusion
Diagnosis of central occlusion is carried out according to the opposite principle - the height of the lower face is determined. There are several ways to determine central occlusion in the absence of teeth:
- anatomical;
- functional-physiological;
- anatomical and physiological;
- anthropometric.
Anatomical and anthropometric methods are based on a detailed study of the proportions of specific lines of the face profile. Anatomical and physiological method of research - identifying the resting height of the lower jaw.
When conducting an external examination, the dentist determines the points at the base of the wings of the nose and chin, and then measures the distance between them.
Afterwards, wax rollers are inserted into the oral cavity and the patient is asked to close the jaw and open it again - this helps to determine the distance. In a normal bite, the indicator should not be higher than 2-3 mm than at rest. If there are any problems, the doctor installs changes in the lower part of the face.
How is treatment carried out?
Misaligned bite can be corrected with specialized orthodontic appliances. If there are mild problems with occlusion, the dentist prescribes a facial massage and the use of removable silicone trays, created according to the individual parameters of the patient.
Bite correction devices are used throughout the day, removed at bedtime and at meals.
In the treatment of occlusion of teeth in children, special face masks are used. Older children are prescribed vestibular plates, Bynin's kappa. According to indications, Frenkel, Klammit and Andresen-Goipl activators are used.
Brace system
Brackets are non-removable orthodontic devices that are created to correct the dentition. deviceeach tooth is fixed in a certain position, and by means of a fastening bracket it corrects the direction of its development, which helps to form a good bite.
Brackets can be vestibular and placed on the front of the crowns, as well as lingual, attached near the tongue.
Brackets-systems are made of metal, ceramics, plastic or combinations. The time of wearing the system will directly depend on the severity of the violation, the age of the patient and following all the advice of a specialist.
Orthodontic appliances
In order to restore the bite, activator devices are also used. The design includes two base plates, which are connected into a monoblock with arcs, brackets and separate rings.
Through this design, the correct position of the lower dentition is restored, the growth of the small jaw is stimulated, and the deep bite is eliminated. In this case, an oblique or corpus displacement of the teeth in a certain direction occurs.
Operating
Surgical measures are carried out with congenital anomalies in the development of the jaws and in the case when other methods do not bring any positive effect. The operation is performed in a hospital under general anesthesia.
The bones are fastened in a certain position, fixed with metal screws and a special splint is placed on them for several weeks. After the patient has to wear a correction device for a long time.
