RU2231995C1 - Method and device for measuring maximum teeth-clenching force - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: method involves measuring maximum jaws-clenching force by fixing a device on tooth surface, applying pressure to the tooth and measuring compression force. The device is set on

tooth. The patient is accommodated in polysomnographic chamber for taking at least 12 h long sleep. The device is withdrawn after the time is over. Balls are taken away and total imprint area of all balls is measured on both sides using microscope and pattern. A plot having the force causing deformation as horizontal axis and the total imprint area of all balls as vertical one is built for determining tooth-clenching force. The device has two metal crowns with 8-9 measuring balls of 2mm large diameter arranged between them. The balls are manufactured from plastic metal alloy. Free space between the crowns is filled with silicon composition. The lower crown repeats occlusion surface of the

tooth and the upper crown repeats one of the lower crown.

EFFECT: high accuracy of measurements in dynamics.

2 cl, 2 dwg

Description

The present invention relates to medicine, namely to dentistry, and relates to measuring the pressure on the teeth exerted by the masticatory muscles during sleep at the time of grinding during bruxism.

The main symptoms of bruxism are hypertonicity of the masticatory muscles, which leads to a disease of the temporomandibular joint, periodontal tissues and pathological abrasion of hard tooth tissues. The consequence of hypertonicity of the masticatory muscles is the lack of relative physiological rest and unprotected, uncontrolled chewing, night gnashing.

Many authors have dealt with questions of measuring the maximum effort to compress teeth.

So, there is a method for determining the threshold of sensitivity of periodontal teeth to chewing pressure and a device for its implementation (see Konyushko DP Orthopedic dynamometer. // Dentistry, 1950, No. 2, p. 51-53).

A known method of measuring the strength of chewing pressure and strain gnatodynamometer for this measurement (see Ivanov A. S. Strain gauge for measuring the transmission of pressure through the teeth on the periodontium // Dentistry, No. 3, 1974, p. 86).

A known method for studying the sensitivity of tooth periodontal to chewing pressure and a device that consists of a metal body having the shape of a cylinder segment, one end of which is closed and the other end has a scale with divisions and an arrow, inside the body there is a spring connected to the tip. To implement the method, the tip of the device is placed on the surface of the studied tooth and the doctor exerts a small, gradually increasing pressure with his hand on the body of the device. The pressure to which the tooth is exposed is indicated by the arrow of the device (see Kleitman I.A. Gnathodynamometer. // Dentistry, 1950, No. 2, pp. 51-53).

The closest analogue is a method of measuring the maximum compression force of the jaws by applying a device including a bite element, applying pressure to it and measuring the compression force (SU 1637782 A1, 03/30/1991).

However, all known methods and apparatus are imperfect, because chewing pressure can be measured only in the patient’s wakeful state, controlled by consciousness, the help and control of the researcher is necessary, when studying the force of contraction of the masticatory muscles, mainly vertical pressure was taken into account.

The technical result of the proposed method and device is to increase the accuracy of measurement by measuring uncontrolled consciousness of chewing pressure during sleep, the ability to perceive chewing pressure in the vertical and horizontal directions and measuring the load in dynamics.

New in achieving the technical result is that the measurement of the compression force of the teeth is carried out according to the results of the dependence of the total area of deformation of the measuring balls of the device on the force of contraction of the masticatory muscles.

Also new is that the measurement is carried out during sleep.

What is new is the fact that the device consists of two metal crowns, the lower one repeating the occlusal surface of the tooth, and the upper one the occlusal surface of the lower crown and 8-9 measuring balls are located between the crowns.

Also new is the fact that the measuring balls have a diameter of 2 mm and are made of ductile metal alloy, and the free space between the crowns is filled with a silicone composition.

Measuring the maximum force of tooth compression during sleep allows you to determine chewing pressure, which is not controlled by consciousness, which is the main damaging factor in bruxism, which increases the accuracy of measurement and also allows you to measure the load in dynamics.

The total area of deformation of the measuring balls of the device allows us to judge the magnitude of the compressive (deforming) force.

The implementation of the device in the form of crowns provides a good fixation of the device on the tooth surface, which in turn provides improved measurement accuracy.

The implementation of the crown corresponding to the occlusal surface of the tooth allows you to not overestimate the occlusal height more than the difference between the height of the relative physiological rest and the height of the central occlusion.

The number and diameter of the measuring balls is determined by the author empirically.

The silicone composition, which fills the free space between the crowns, ensures the fixation of the balls and holds the crowns together, which increases the measurement accuracy.

Comparative analysis shows that the claimed method and device differ from the prototype in that the measurement of tooth compression is carried out according to the results of the dependence of the total area of deformation of the measuring balls of the device on the force of contraction of the masticatory muscles, and the measurement is carried out during sleep; the device consists of two metal crowns, with the lower crown repeating the occlusal surface of the tooth and the upper crown the occlusal surface of the lower crown, while between the crowns there are 8-9 measuring balls with a diameter of 2 mm made of a plastic metal alloy, and the free space between the crowns is filled with silicone composition that meets the criteria of the invention of "novelty."

A new set of essential features allows to increase the accuracy of measurement by measuring the uncontrolled consciousness of chewing pressure during sleep, provides the ability to perceive chewing pressure in the vertical and horizontal directions and measure the load in dynamics, which meets the criteria of the invention “industrial applicability”.

The method is as follows. Previously, to obtain a template for measuring the value of force, a series of model devices with the same specified number of measuring balls is made. The device is squeezed on a reference press with different strengths and the area of prints is determined on a measuring microscope.

To measure the maximum tooth compression force, the device is applied to 6; tooth, fix it on Repin paste and leave at 12 o’clock from 20 o’clock in the evening to 8 o’clock in the morning. For this, the patient is placed in a polysomnographic office. The device is removed in the morning, the balls are taken out, flat prints remain on their surface as a result of plastic deformation. Under the microscope, using the template with the divisions, the total area of deformation is determined. According to the results, a graph is constructed where the value of the deforming force in kg of force is plotted on the horizontal axis, and the total area of the diameters of the prints of all balls on both sides in square millimeters is plotted on the vertical axis. The magnitude of the maximum tooth compression force determines the degree of bruxism and treatment tactics.

The proposed device is shown in figure 1, where 1 is the lower crown, 2 is the upper crown, 3 are measuring balls, 4 is a silicone composition.

The device consists of two metal crowns 1 and 2, the lower crown repeats the occlusal surface of the tooth. The upper crown follows the shape of the lower crown. Measuring balls 3 are located between the crowns. The measuring balls are made of shiny white metal alloy, which contains tin 94-96% and lead 4-6%. The free space between the crowns 1 and 2 is filled with a silicone composition 4, which fixes the measuring balls 3 and holds the crowns 1 and 2 together. The diameter of the balls is 2 mm, the number is 8-9 pieces.

The proposed method and device is illustrated by the following clinical example.

Patient Berieva Oksana Gennadievna, 18, a student, turned to the orthopedic dentistry clinic with complaints of gnashing of teeth during sleep, a change in appearance, pain in the masticatory muscles in the morning, aching pains in the temporomandibular joint, upper and lower jaw. Anamnesis: grinds his teeth from early childhood. Chewing muscle pain appeared 4 years ago. I turned to the otolaryngologist, neurologist, but no pathology was detected by the ENT organs. The neuropathologist prescribed tranquilizers, but this did not help. In addition to night gnashing and pain, the patient notes difficulty falling asleep or insomnia, late waking, headaches, pressing in the temples and frontal region of the head, short temper, tearfulness, restraint, depression, trembling at an unexpected sound or touch, cramps in the calf muscles, fatigue , decreased concentration, dizziness, menstrual irregularities, cold and wet hands, oily seborrhea of the scalp. His father rattled at night, he died at the age of 32 of alcoholism, his mother, his grandmother's dad's pedigree. Objectively: Extraoral-asymmetry of the face, the lower jaw is shifted to the right, the lower third of the face is not changed. The lower jaw when opening makes a zigzag movement, the maximum opening of the mouth is 3.5 cm (normal 4.5-5 cm). Masticatory muscles, temporal and proper masticatory hypertrophied, painful on palpation. Dense. Palpation of the temporomandibular joint area is painless. The height of the lower third of the face in a state of relative physiological rest is 6.4 cm and in the position of central occlusion is also 6.4 cm. Intraoral: on the mucous membrane of the cheeks along the line of closure of the teeth and on the side surface of the tongue there are tooth prints.

Dental formula

имеются площадки патологической стираемости, тремы и диастемы, слизистая оболочка десны слегка гиперемирована, имеется видимое оголение цемента корня на 1 мм, глубина десневого кармана в области 21 12 составляет 1 мм. Межрезцовая линия верхней и нижней челюсти не совпадает, на нижней челюсти смещена вправо на 3 мм. Миотонометрическое исследование показало, что тонус височной мышцы справа и слева в расслабленном состоянии составляет 120 г, в напряжении 130 г, жевательной мышцы слева и справа в покое - 90 г, в напряжении 135-140 г. Для того чтобы поставить диагноз “бруксизм”, необходимо зафиксировать “скрежетание” во время сна и определить, с какой силой жевательные мышцы сокращаются. Для этого пациента помещают в полисомнографический кабинет, где начиная с 20 часов и до 8 часов утра синхронно записывают электромиографию, электроэнцефалографию и гнатодинамометрию. Максимальное сжатие челюстей определяют с помощью устройства, которое накладывают на 6; зуб и фиксируют на пасту репин. Утром устройство снимают, открывают и вынимают измерительные шарики. Под микроскопом при помощи шаблона с делениями определяют суммарную площадь деформации и строят график. Общая площадь деформации составила 2,6 мм², а максимальное усилие 17 кг (см. фиг.2). На основании этого был поставлен диагноз обследуемой больной: Бруксизм. Средней степени тяжести. Вторичная деформация зубного ряда и прикуса, болевой дисфункциональный синдром височно-нижнечелюстного сустава.In the region of

there are areas of pathological abrasion, trema and diastema, the mucous membrane of the gum is slightly hyperemic, there is a visible exposure of root cement by 1 mm, the depth of the gingival pocket in the region of 21 12 is 1 mm. The interdental line of the upper and lower jaw does not coincide, on the lower jaw it is shifted to the right by 3 mm. Myotonometric study showed that the tone of the temporal muscle in the right and left in a relaxed state is 120 g, in tension of 130 g, chewing muscle in the left and right at rest - 90 g, in tension of 135-140 g. In order to make a diagnosis of “bruxism”, it is necessary to fix the “gnashing” during sleep and to determine with what force the masticatory muscles contract. For this patient, they are placed in a polysomnography room, where, starting from 8 p.m. and until 8 a.m., electromyography, electroencephalography, and gnatodynamometry are simultaneously recorded. The maximum compression of the jaws is determined using a device that is superimposed on 6; tooth and fix on paste repin. In the morning, the device is removed, opened and the measuring balls are removed. Under the microscope, using the template with divisions, the total area of deformation is determined and a graph is constructed. The total area of the deformation was 2.6 mm ² and the maximum force of 17 kg (see figure 2). Based on this, the patient was diagnosed with: Bruxism. Moderate severity. Secondary deformation of the dentition and bite, pain dysfunctional syndrome of the temporomandibular joint.

Claims (2)

1. The method of measuring the maximum compression force of the jaws by applying the device to the tooth surface, applying pressure on it and measuring the compression force, characterized in that the device according to claim 2 is fixed at 6; the tooth, the patient is placed in a polysomnography office for sleeping for at least 12 hours, after the specified time the device is removed, the balls are removed and the total area of the prints of all balls on both sides is measured under the microscope using a template, then to determine the maximum tooth compression force, a graph where on the horizontal axis the magnitude of the deforming force is plotted, and on the vertical - the total area of the prints of all the balls on both sides. 2. A device for maximum compression force of the teeth, including a bite element, characterized in that it is made in the form of two metal crowns, between which there are 8-9 measuring balls with a diameter of 2 mm made of plastic metal alloy, and the free space between the crowns is filled with silicone composition, while the lower crown repeats the occlusal surface 6; tooth, and the upper one is the occlusal surface of the lower crown.

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