RU2789594C1 - Device for obtaining mri images of the temporomandibular joint in specified positions of the lower jaw and method for using it - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: inventions group relates to medicine. The device for obtaining MRI images of the temporomandibular joint consists of a palatal plate made of self-hardening plastic. At the same time, at the location of the teeth, recesses are made in the given positions of the central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw, with the possibility of fixing the teeth of the patient's lower jaw. When implementing the method for obtaining MRI images of the temporomandibular joint, the device is fixed on the upper jaw, the patient is placed in the MRI machine. Then the patient compresses the jaw sequentially in the given positions: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw. In this case, the lower jaw is fixed due to the recesses made on the device. At each given position of the lower jaw, an MRI image of the temporomandibular joint is obtained.

EFFECT: use of this group of inventions will provide clear MRI images of the TMJ in the specified positions of the lower jaw with long-term fixation.

2 cl, 5 dwg, 1 ex

Description

The claimed technical solution relates to dental devices and methods, designed to obtain dynamic MRI images of the elements of the temporomandibular joint (TMJ), in particular, the head of the lower jaw (condyle) and the intraarticular disc in the given positions of the lower jaw.

Currently, when obtaining MRI images of the elements of the temporomandibular joint (TMJ), in particular, the head of the lower jaw (condyle) and intraarticular disc, there is a problem of ensuring long-term fixation of the lower jaw at its various positions during the shooting, since as a result of the duration of the shooting it is difficult for the patient to keep the jaw in one position. Existing technical solutions solve this issue by using additional devices, such as clasps, which increases the cost of the process and makes it less technologically advanced. Without the use of additional devices, the shooting time increases due to the need to take repeated shots due to jaw movement and the image quality decreases.

Further in the text, the applicant gives the terms that are necessary to facilitate an unambiguous understanding of the essence of the claimed materials and to exclude contradictions and / or controversial interpretations when performing an examination on the merits.

TMJ - temporomandibular joint.

The palatine plate is a plate for the upper jaw with a vestibular arch and an inclined plane, it is a base plate with clamp fixation, a mechanically acting element - a vestibular arch (ordinary, multi-link or with pressure loops) and an inclined plane - a functional guiding element. Depending on the indications, expanding elements (screws or springs), springs for moving individual or groups of teeth in different directions can be introduced into the device design [https://studfile.net/preview/6204478/page:16/].

Klammer (clothespin, bracket) - a fixing element covering part of the tooth surface and helping to hold the prosthesis on the jaw [https://ru.wikipedia.org/wiki/Klammer_(medicine)].

From the studied level of technology, an invention was revealed according to the patent of the Russian Federation No. 2533737 "Method of magnetic resonance imaging diagnostics of the articular disc of the temporomandibular joint", which is analogous to the method. The essence is a method of magnetic resonance imaging diagnostics of the articular disc of the temporomandibular joint (TMJ), including the performance of MRI of the right and left TMJ using a standard coil for examining the brain, a magnetic field strength of 3 T, in a position with a closed and maximally open mouth, which differs by the fact that the joint is additionally examined in the position of a partially open mouth - lowering the lower jaw down without pushing it forward, and in the position with the mouth closed, MRI is performed in oblique sagittal and oblique frontal projections, in the position of a partially open and maximally open mouth - in an oblique sagittal projection , in each projection in each position of the joint, the study is carried out for 1 minute, the slice thickness is 2 mm, the interval between slices is 0 mm.

The disadvantage of the known technical solution is the lack of fixation of the lower jaw in the given positions, which leads to:

- to increase the time of MRI examination,

- less accurate diagnosis of TMJ pathologies.

A technical solution [https://studfile.net/preview/6204478/page:16/], namely, a device - a palatine plate with an inclined plane for separating the occlusion with an anterior displacement of the lower jaw, which is analogous to claimed device. The essence is a plate on the upper jaw with a vestibular arch and an inclined plane, which is a base plate with clamp fixation, a mechanically acting element - a vestibular arch (ordinary, multi-link or with pressure loops) and an inclined plane - a functional guiding element. Depending on the indications, expanding elements (screws or springs), springs for moving individual or groups of teeth in different directions can be introduced into the design of the device. The indication for use is a prognathic distal occlusion - according to the classification of L.P. Grigoryeva, II ₁ - according to the classification of E. Angle, prognathia - according to D.A. Kalvelis, distal bite - according to A.I. Betelman. The vestibular arch changes the inclination of the upper anterior teeth in the oral direction, subject to the availability of space, and also delays the growth of the anterior region. The inclined plane contributes to the mesial displacement of the lower jaw and a change in the inclination of the lower frontal teeth during their retrusion; if necessary, it is possible to separate the bite in the lateral areas and stimulate dentoalveolar elongation (with deep incisal overlap).

The disadvantages of the known technical solution in comparison with the claimed technical solution is the impossibility of using the known plate for diagnosis in MRI studies due to the design features (since the known plate is intended solely for correcting the bite pathology):

- the absence of fixing recesses for various positions of the lower jaw;

- a more complex design, since fixation is carried out using clasps.

The technical result of the claimed technical solution is the development of a device for obtaining an MRI image of the temporomandibular joint in given positions of the lower jaw and a method of using it, allowing to achieve:

• in relation to the device:

- ensuring long-term fixation of the lower jaw due to the presence of fixing recesses for different positions of the lower jaw;

- less complex design, since fixation is carried out without the help of additional elements - clasps;

• in relation to the method:

– Obtaining clear MRI images of the TMJ in given positions of the lower jaw with long-term fixation, which, in turn, leads to:

- to reduce the time of MRI examination;

- providing the possibility of more accurate diagnosis of TMJ pathologies.

In this case, the claimed technical solution is characterized by:

- convenience for the patient,

- low trauma

- simple design,

- does not require significant material costs,

– the possibility of application in practical medicine, tk. was tested in the laboratory of the Institute of Fundamental Medicine and Biology of the Kazan (Volga Region) Federal University.

The essence of the claimed technical solution is a device for obtaining MRI images of the temporomandibular joint, consisting of a palatine plate made of self-hardening plastic, while at the location of the teeth, recesses are made in the given positions of central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw, with the possibility of fixing the teeth of the lower jaw of the patient. A method for obtaining MRI images of the temporomandibular joint, which consists in the fact that the device according to claim 1 is fixed on the upper jaw, the patient is placed in the MRI machine, then the patient compresses the jaw sequentially in the specified positions: central occlusion, anterior occlusion, lateral occlusions, at maximum retroposition of the jaw, while the lower jaw is fixed due to the recesses made on the device, while at each given position of the lower jaw, an MRI image of the temporomandibular joint is obtained.

The claimed technical solution is illustrated in Fig.1 - Fig.5.

Figure 1 shows a plaster model of the upper jaw (lilac), which is wearing the claimed device for the implementation of the MRI image of the TMJ in the specified positions of the lower jaw (pink).

On FIG. 2 shows an impression of the patient's upper jaw.

Figure 3 shows a plaster model of the upper jaw.

Figure 4 shows a plaster model of the upper jaw with the installed palatine plate.

Figure 5 shows the formation of fixing recesses for each position of the lower jaw in the patient's mouth:

5a - the position of the central occlusion,

5b - the position of the left lateral occlusion,

5c - the position of the right lateral occlusion,

5d - position of the anterior occlusion,

5d - the position of the maximum retroposition of the jaw.

Next, the applicant provides a description of the claimed technical solution.

The claimed technical solution is intended for obtaining MRI images of the elements of the temporomandibular joint (TMJ), in particular, the head of the lower jaw (condyle) and the intraarticular disc in the given positions of the lower jaw, for example, central occlusion, anterior occlusion, lateral

occlusions, as well as with the maximum retroposition of the jaw due to the presence of fixing recesses for each position of the lower jaw.

Before an MRI examination, the claimed device is installed in the oral cavity in the form of a palatal plate containing in the anterior section fixators of the position of the lower jaw in the form of recesses for the lower incisors, and MRI is taken.

Further, the applicant provides a description of the claimed device.

The claimed device consists of a palatine plate made of self-hardening plastic, while at the location of the teeth, recesses are made, located with the possibility of fixing the teeth of the patient's lower jaw.

The claimed device is manufactured as follows .

The claimed device is manufactured by a clinical laboratory method, while the fixing recesses for the lower incisors for each position of the jaw are formed by the doctor directly in the oral cavity as follows.

Remove the cast of the upper jaw of the patient (Figure 2).

Then, a plaster model is cast according to the cast (Figure 3).

Then they take self-hardening plastic, for example, brand Zhermark ELITE LC Tray [https://adeo.dental/product/elit-lc-tray-pink---rozovyy--50-sht----svetootverjdaemye-plastiny-dlya-individ --lojek--zhermack-140856], it is pressed over the vestibular and palatal surfaces of the plaster model from the left premolar to the right premolar and polymerized, for example, in a polymerizer, for example, the Megalight ST brand [https://stomshop.pro/megadenta-megalight -st], for example, 5 minutes. Then sharp edges are smoothed using, for example, a bur or cutter (Figure 4).

Then the resulting palatine plate is installed in the patient's mouth, articulation paper is introduced into the oral cavity, the patient compresses the jaw, while on the palatine plate there are imprints from closing with the teeth in the following positions: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw.

Then the palatine plate is removed, and in places of imprints from contact with the teeth, recesses are made to fix the teeth of the patient's lower jaw. The recesses are made, for example, with a bur or a cutter.

Thus, in the claimed device, in comparison with the known technical solution, there are fixing recesses for each position of the lower jaw, for example, at the maximum retroposition of the jaw, central occlusion, anterior occlusion and lateral occlusions, which allows to achieve the claimed technical result.

Further, the applicant shows the sequence of actions of the claimed method for obtaining an MRI image of the temporomandibular joint in given positions of the lower jaw.

The claimed device is taken, fixed on the upper jaw, the patient is placed in the MTP apparatus.

Then the patient compresses the jaw sequentially in the given positions: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw. While the lower jaw is fixed due to the recesses made on the claimed device.

In this case, at each given position of the lower jaw, an MRI image of the temporomandibular joint is obtained.

This achieves a clear image due to the possibility of long-term fixation of the jaw.

Further, the applicant gives an example of the implementation of the claimed technical solution.

Example. Obtaining an MRI image of the temporomandibular joint in specified positions of the lower jaw

Patient K., aged 48, received an MRI image of the temporomandibular joint in the specified positions of the lower jaw on the claimed device by the claimed method as follows.

A cast of the patient's upper jaw was taken (Figure 2).

Then, according to the cast, a plaster model was cast (Figure 3).

Then they took a self-hardening plastic, for example, the brand Zhermark ELITE LC Tray [https://adeo.dental/product/elit-lc-tray-pink---rozovyy--50-sht----svetootverjdaemye-plastiny-dlya-individ --lojek--zhermack-140856], it was compressed along the vestibular and palatal surfaces of the plaster model from the left premolar to the right premolar and polymerized, for example, in a polymerizer, for example, the Megalight ST brand [https://stomshop.pro/megadenta-megalight -st], for example, 5 minutes. Then smoothed the sharp edges using, for example, cutters (Fig.4).

Then the resulting palatine plate was installed in the patient's oral cavity, articulation paper was introduced into the oral cavity, the patient clenched his jaw, while the palatine plate left imprints from closing with the teeth in the position: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw.

Then the palatal plate was removed, and in places of imprints from the closure with the teeth, recesses were made to fix the teeth of the patient's lower jaw. The recesses were made, for example, with boron.

Then, to obtain an MRI image, the claimed device was fixed on the upper jaw and the patient was placed in the MRI machine.

Then the patient clenched the jaw sequentially in the given positions: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw. In this case, the lower jaw was fixed due to the recesses made on the claimed device.

At the same time, at each given position of the lower jaw, a clear MRI image of the temporomandibular joint was obtained due to the possibility of long-term fixation of the jaw with the help of recesses.

At the same time, short MRI examination time and accurate diagnosis of TMJ pathologies were ensured, since there was no jaw displacement, which did not require additional time and repeated images. At the same time, the patient experienced less discomfort due to more comfortable fixation of the jaw.

Thus, from the foregoing, we can conclude that the applicant has achieved the claimed technical result, namely, a device has been developed for obtaining an MRI image of the temporomandibular joint in specified positions of the lower jaw and a method of using it, which made it possible to achieve:

• in relation to the device:

- ensuring long-term fixation of the lower jaw due to the presence of fixing recesses for different positions of the lower jaw;

- less complex design, since fixation is carried out without the help of additional elements - clasps;

• in relation to the method:

– obtaining clear MRI images of the TMJ in the given positions of the lower jaw with long-term fixation, which, in turn, led to:

- to reduce the time of MRI examination;

- providing the possibility of more accurate diagnosis of TMJ pathologies.

In this case, the claimed technical solution is characterized by:

– convenience for the patient;

- low trauma

- ease of implementation,

- does not require significant material costs,

– the possibility of application in practical medicine, as it was tested in the laboratory of the Institute of Fundamental Medicine and Biology of Kazan (Volga Region) Federal University.

The claimed technical solution satisfies the "novelty" patentability condition for inventions, since as a result of the analysis of the prior art, the applicant has not found a tool that has features that are identical (that is, matching in the function they perform and the form of execution of these features) to all the features listed in an independent claim, including a description of the purpose.

The claimed technical solution satisfies the condition of patentability, "inventive step" for inventions, because it is not obvious to a person skilled in the art.

The claimed technical solution satisfies the condition of patentability, "industrial applicability" for inventions, because was tested in practice in the laboratory of the Institute of Fundamental Medicine and Biology of the Kazan (Volga Region) Federal University, as a result of which all the technical results stated in the claimed technical solution were implemented.

Claims (2)

1. A device for obtaining MRI images of the temporomandibular joint, consisting of a palatal plate made of self-hardening plastic, while at the location of the teeth, recesses are made in the given positions of central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw, with the possibility fixation of the teeth of the lower jaw of the patient. 2. A method for obtaining MRI images of the temporomandibular joint, which consists in the fact that the device according to claim 1 is fixed on the upper jaw, the patient is placed in the MRI machine, then the patient compresses the jaw sequentially in the specified positions: central occlusion, anterior occlusion, lateral occlusions, with the maximum retroposition of the jaw, while the lower jaw is fixed due to the recesses made on the device, while at each given position of the lower jaw, an MRI image of the temporomandibular joint is obtained.

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