Bioelectric Activity Of Muscles Research Articles

Neurophysiological assessment of the condition of the masticatory muscle group in patients with occlusion disorders and chronic generalized periodontitis

Background. Recently, the interest of dentists and physiologists has been focused on the development of a set of informative computerized techniques for an objective analysis of the functional state of the dentofacial apparatus. Achieving certain successes in conducting functional diagnostic examinations contributes to the development of algorithms for complex treatment of patients with generalized periodontitis and premature occlusal contacts.Goal. Study of the functional state of the dentofacial apparatus according to the parameters of bioelectrical activity of muscles in patients with chronic generalized periodontitis and occlusal disorders in static and dynamic conditions of the lower jaw.Materials and methods. The study involved 37 people with clinically healthy periodontium, physiological occlusion, and absence of occlusal disorders (Group 1) and 45 patients with physiological types of occlusion, generalized chronic periodontitis and premature occlusal contacts (Group 2). Functional methods included electronic registration of occlusal relationships with the T-Scan® III computer occlusion analysis system and study of the bioelectrical activity of the masticatory muscles using the Bio-EMG® III electromyography using standard functional tests.Results. In patients of group 2, in comparison with patients of group 1, neuromuscular discoordination of the functional activity of the masticatory muscles was diagnosed. This condition is confirmed by the asymmetry and lack of muscle synergy when performing the “Maximum volitional compression” test, an improvement in the symmetry of the work of the muscles of the same name on the right and left sides and the synergy of the work of the muscles of the right and left masticatory groups, as well as a statistically significant increase in the values of biopotentials m. temporalis and m. masseter during the “Maximum volitional compression on rollers” test.Conclusions. Disturbances in the coordinated work of the muscles of the craniofacial region in patients with chronic generalized periodontitis and premature occlusal contacts are realized in a statistically significant increase in the biopotentials of the masticatory muscle group at rest, a decrease in biopotentials during functional loading, as well as a reduction in the values of symmetry and synergy in relation to similar values patients of group 1.

EMG ACTIVITY OF MUSCLES OF THE CRANIOMANDIBULAR SYSTEM IN SUBJECTS WITH NARROWING UPPER JAW AND POSTERIOR CROSSBITE

Posterior crossbite in children and adolescents has been linked to asymmetrical function and performance of the masticatory muscles. Electromyography (EMG) serves as an objective and widely applicable evidence-based method for diagnosing muscle function. The aim of our study was to analyze electromyographic (EMG) activity of muscles of the craniomandibular system in subjects with a narrowing upper jaw and unilateral posterior crossbite. Material and methods. The first (study) group consisted of 18 subjects with narrow maxilla and unilateral posterior crossbite. 20 age-matched children with normal occlusion were included in the control group. The average age of subjects in the study group was 8.4±1.4 years, in the control group – 8.8±1.6 years. The exclusion criteria of the study were as follows: previous or active orthodontic treatment, clefts, traumas in the maxillofacial region, and general diseases. EMG activity of the anterior temporal, masseter, sternocleidomastoid (SCM), orbicularis oris, and mentalis muscles on both sides (left and right) was recorded during two 30-second tests: maximum voluntary clenching and swallowing a sip of water. Maximum voluntary clenching was performed in the intercuspal position. EMG data were processed using Neurotech's Synapsis software. EMG activity for each muscle was estimated by the maximum amplitude of the muscle contractions (μV). Results. EMG activity in children with narrowing upper jaw and unilateral posterior crossbite of anterior temporal, masseter, and sternocleidomastoid muscles was asymmetrical and differed between the left and right sides. Higher bioelectrical muscle activity was found on the crossbite side for the masseter and anterior temporalis muscle, and on the opposite side – for sternocleidomastoid muscles. Values of maximum amplitude of sternocleidomastoid muscles were higher in the study group than in the control group without significant difference. There was a statistically significant difference in EMG activity of mentalis and orbicularis oris muscles between the two groups of children (p<0.05). Values of EMG activity of mentalis and orbicularis oris were higher in the study group.

ANALYSIS OF THE BIOELECTRICAL ACTIVITY OF THE MASTICATORY MUSCLES, DEFINED ACCORDING TO BERNOULLI'S PRINCIPLE AS "STRONG" OR "FAST", FOR THE PREDICTION OF PATHOLOGICAL TOOTH ABRASION (ACCORDING TO MAGNETIC RESONANCE IMAGING AND ELECTROMYOGRAPHIC STUDIES)

Pathological abrasion is a well-known disease, but it is topical issue of hard dental tissues. The principle of D. Bernoulli and its numerical expression in the form of the coefficient “k” were used. It is calculated by the formula , where k is the calculated coefficient; l is the length of the muscle in this case, the masseter separately on the right and left; s is the cross-sectional area of the muscle. The masseter muscles' length, width, and thickness were determined using SIEMENS MAGNETOM Skyra 3T magnetic resonance imager, 2018.
 The classical method was used for the electromyographic study of the masseter muscles. We analysed 64 MRI scan results, of which 15 were control subjects with intact dentitions, and 49 were patients with varying degrees of tooth abrasion. After determining the physical parameters as length, width, and thickness of the masseter muscles on the right and left sides, the cross-sectional area of the muscles was determined and the author's coefficient of the numerical expression of the Bernoulli principle for each masseter was proposed.
 Electromyograms of the masseter muscles in the mode of free chewing were recorded for all subjects with subsequent software analysis. Extrapolation of the obtained coefficients of the numerical expression of the Bernoulli principle of the left and right masseter muscles to the values of quantitative and qualitative indicators of electromyograms of the same muscles revealed a direct dependence of the bioelectrical activity of muscles on the ratio of muscle length to cross-sectional area. Higher values of this coefficient correspond to higher values of bioelectrical bursts of muscle activity, faster contraction and relaxation, shorter chewing time, and longer resting time of the muscle, which is a sign of the biomechanical property "speed". Masseter muscles with such properties are observed in individuals without pathological tooth abrasion. In the groups of patients with pathological tooth abrasion, a decrease in the ratio of the length of the masseter to its crosssectional area is observed in proportion to the increase in the severity of the pathological process. The amplitude of muscle bioelectrical activity bursts decreases, the speed of excitation and relaxation processes decreases, the chewing time is prolonged, and the resting time is reduced, which indicates that the muscle acquires the biomechanical property of "strength". "Fast" masseter muscles do not cause pathological tooth abrasion, while "strong" muscles contribute to the development of pathological tooth abrasion. Employing both Bernoulli's principle and MRI studies on the muscles responsible for mandibular movements will enable a comprehensive investigation into the progression of localized pathological tooth abrasion and provide a more intricate understanding of the muscles' impact on the development of dentoalveolar anomalies.

Experimental studies of a soft industrial exoskeleton in work-related activity for the evaluation of its operational efficiency

For conducting the experiment under laboratory conditions, a dedicated workplace was designed to simulate the activity of lifting / lowering a 20 kg load to a height of 0.7 m in the “Squat” and “Stoop” styles. To implement this study, the following methods were employed: “motion capture” to assess the mechanics of movements in the lumbar spine; a non-invasive method for measurement of the key biological indicators as a comprehensive assessment of the state of the cardiorespiratory system; electromyography (EMG) as the main method for assessing the bioelectrical activity of muscles; interviewing volunteers (on a 10-point scale) as a method of subjective assessment of their physical condition and performance. A study conducted as part of the work meant to determine the effectiveness and safety of using a soft industrial exoskeleton during work-related activity, including the elimination of the harm from stereotypic work movements, showed a decrease in the activity of the measured muscles when using a soft industrial exoskeleton, which also indicates a decrease in human fatigue that increases the effectiveness of its operation.

In search of biomarkers for low back pain: can traction therapy effectiveness be prognosed by surface electromyography or blood parameters?

Background: Lumbar traction therapy is a common method to reduce low back pain (LBP) but is not always effective. The search for biomarkers that would prognose the effectiveness of LBP management is one priority for improving patients' quality of life. Objectives: 1) To determine the phenotype of patients benefiting most from lumbar traction therapy. 2) To correlate systemic and electromyographic biomarkers with pain and pain-related disability. Methods: Data on muscle bioelectrical activity (surface electromyography [SEMG]) in the flexion-extension task, the concentrations of twelve systemic biochemical factors, LBP intensity (Visual Analog Scale), the Oswestry Disability Index, and the Roland-Morris Disability Questionnaire (RMDQ) were collected before and 72h after 20 sessions of lumbar traction therapy. Patients were divided into responders and nonresponders based on the criterion of a 50% reduction in maximal pain. Results: The responders had lower maximal muscle bioactivity in the extension phase on the left side (p < 0.01) and higher flexion-extension ratios on both sides of the body in the SEMG (left: p < 0.05; right: p < 0.01), and higher adipsin, interleukin-2, interleukin-4, and interleukin-10 concentrations (p < 0.05) than nonresponders. Patients with higher interleukin-4 concentrations before therapy achieved greater reductions in maximal pain in the sitting position, bioelectrical muscle activity in flexion, and flexion-relaxation ratio on the left side of the body. Changes in adipsin and interleukin-4 concentrations correlated with changes in LBP intensity (r = 0.68; r = -0.77). Changes in stem cell growth factor and interleukin-17A correlated with changes in RMDQ (R = 0.53) and bioelectrical muscle activity in extension (left: R = -0.67; right: R = -0.76), respectively. Conclusion: Responders to traction therapy had SEMG indices of less favorable muscle activity in the flexion-extension task and elevated indices of inflammation before the study. For the first time, interleukin-4 was indicated as a potential biomarker for prognosing post-therapy changes in pain intensity and muscle activity.

Study of the impact of using the industrial exoskeleton to support the upper limbs on the condition of the arms and shoulder girdle muscles

Introduction. The level of occupational morbidity associated with the effects of physical overload and overstrain of individual organs and systems indicates the need for timely and effective prevention, one of the means of which is the introduction of a promising type of PPE — industrial exoskeletons. Since there are no clear requirements and criteria of their safety and efficiency, all the researches in this field are of experimental character, which dictates the necessity of testing each particular type of exoskeleton in relation to the performance of certain labor operations.&#x0D; The study aims assess the influence of using industrial exoskeleton for support of upper limbs on the arm and shoulder girdle muscles fatigue.&#x0D; Materials and methods. The researchers used the presented industrial exoskeleton designed to reduce the load on the upper limbs when performing work above the level of the user's head. Eleven healthy volunteers participated in the study. In laboratory conditions, the authors simulated labor activity similar to work on an automobile conveyor with a gravity class 3.2.&#x0D; During the work, both without the use of an industrial exoskeleton and with its use, scientists measured the bioelectric activity of the muscles of the upper extremities and shoulder girdle on both sides using surface EMG. In addition, before and after the work, the authors performed myotonometry and dynamometry in order to register the biomechanical properties of the studied muscles, as well as strength and endurance of the hands.&#x0D; Results. As a result of recording the EMG-signal, scientists found that the activity of the anterior deltoid muscle on the right and the biceps muscle of the shoulder on the right when using an industrial exoskeleton in work is reduced by more than 50%. The indicators of endurance and strength recorded during dynamometry decreased after performing work both with and without an exoskeleton, from 1% to 36%, but their dynamics did not fully correspond to classical ideas about the development of muscle fatigue. The analysis of myotonometry data did not show statistically significant changes in the parameters of the studied muscles.&#x0D; Limitations. The limitations of this study are: a small sample size (eleven volunteers), the lack of calculation of the sample size, the use of a small set of used biomedical methods for assessing the human condition.&#x0D; Conclusion. The use of the studied industrial exoskeleton when performing simulated labor operations reduces the bioelectric activity of the main muscles involved in the work, which proves its effectiveness. The developed technique of surface EMG can be used in the future when carrying out such work. Dynamometry and myotonometry did not show sufficient sensitivity in the study, which necessitates the development of special techniques for solving similar problems.&#x0D; Ethics. The Local Ethics Committee of Izmerov Research Institute of Occupational Health have approved the Protocol of the study (the protocol No.3 dated 04/20/2022).

Стан мімічних та жувальних м’язів у людей похилого віку з повною втратою зубів, які користуються повними знімними протезами (ПЗП)

Resume. Masticatory and facial muscles are an integral part of the gnathological system. Their coordinated work ensures synchronous operation of the chewing apparatus, swallowing functions, and speech. The functional state of the muscles of the maxillofacial area is interconnected and interdependent with the work of the TMJ. But over time, a person loses teeth, of course, all this affects the coordination, condition and work of the chewing muscles. Of particular interest is the work of the masticatory and mimic muscles in the age group after 75 years in people who have been using complete removable prostheses(CRPs) for a considerable time, against the background of pronounced processes of atrophy of the maxillofacial area. During this time, the structural elements of the CRPs change, prostheses wear out, and the height of the bite changes significantly. Clinical studies prove that masticatory and facial muscles take part in the maintenance of the CRPs during the functions of the oral cavity. In such conditions, these muscles are constantly in a state of adaptation to those changes that occur with the chewing apparatus. One of the indicators of the condition of the masticatory muscles is their bioelectric activity. Keywords: electromyography, coefficient k, bioelectric activity, bioelectric rest, temporal muscle, masseter muscle, orb muscle, mandible, bioelectric activity of muscles, complete removable prostheses(CRPs).

Myofascial Facial Massage in Correction of Stress, Anxiety and Depressive Symptoms: a Сase Report

INTRODUCTION. At present, neuropsychiatric disorders are widespread among the population. Their occurrence is associated with the effect of chronic emotional stress. However, most people are not ready to seek help from a psychologist or psychotherapist. The original technique of decreasing the bioelectrical activity of facial muscles, developed and described in this study, can be an affordable and safe way to correct psycho-emotional states and, consequently, improve the aesthetic appearance. AIM. To develop a modern method of correction of psychoemotional derivations, based on the use of neuromuscular relaxation techniques and the development of a facial feedback mechanism. MATERIAL AND METHODS. The research methods included psychological, neurophysiological, and clinical-functional components that allowed assessing the psychoemotional status and electrophysiological parameters of the facial muscles. RESULTS AND DISCUSSION. The results have shown a high efficiency of neuromuscular relaxation methods in the correction of psychoemotional disorders, which was manifested in reducing the level of depressiveness, situational and personal anxiety and increasing the bioelectric activity of the facial muscles, as well as the state of parafunction It have become possible to establish a clear correlation between the presence of severe depression and anxiety and increased electrical activity of the facial muscles, and the data obtained suggested that the use of neuromuscular relaxation techniques is an effective psychocorrective. СONCLUSION. The method of neuromuscular relaxation is a new effective tool for diagnosing psychoemotional derivations and increasing the tonus of facial muscles by creating facial feedback.

MYOFASCIAL NECK PAIN SYNDROME IN WRESTLING ATHLETES: PREVENTION AND RECOVERY

Abstract. Early sports specialization, increased professional load, technical complexity of motor elements, lack of adequate means of rehabilitation in the training process have become the main triggers in the emergence of MNPS. The aim of the study was to study the mechanisms of development, clinical manifestations and development of the etiological system of treatment of cervical myofascial pain in the absence of actual organic pathology of the spine. Promising treatment is the use of reflexology. Effects of reflexology: analgesia, psychiatric (depression, sedation), nutrition, recovery, muscle relaxation. Conclusions: Athletes are mainly characterized by pain in the muscles that provide static work, as well as different options for the distribution of MNPS, depending on the sport. The upper and lower extremities are involved in performing active motor functions characteristic of sports. In general, local symptoms of pain were observed in 52.5% of athletes, and common - in 40.6%. At the same time, MNPS was most common in 63.4% of cases of cervical wrestlers and 58.4% of cases of lumbosacral region; in athletes, the development of myofascial disorders increases the bioelectrical activity of muscles at rest; Athletes with common symptoms have reduced control processes in the central nervous system [1]. It is characterized by an increase in multisynaptic reflex excitability at the level of the brain stem; emotional disorders in athletes in the presence of myofascial pain are characteristic in the presence of the third stage of the pathological process; the occurrence of general symptoms of MNPS according to the study leads to an increase in the average time of sensorimotor response, deterioration of motor processes and increased fatigue when performing a series of tests; MNPS treatment, which includes reflexology and PIR programs based on clinical and instrumental studies, significantly improves the athlete's condition during 12 months of follow-up.

The Axial Length of the Eyeball and Bioelectrical Activity of Masticatory and Neck Muscles: A Preliminary Report.

Objective The present study aimed to evaluate the correlation of eye length and bioelectric activity of temporalis, masseter, digastric, and sternocleidomastoid muscles in women with myopia compared to healthy women. Methods Based on the exclusion and inclusion criteria, 42 women aged 24 years (±2 years) were eligible for the study. Two equally sized groups with myopic (n = 21) and emmetropic healthy subjects (n = 21) were formed. An electromyographic study of the examined muscles was performed in four conditions: at rest, during maximal voluntary clenching in the intercuspal position, during maximal voluntary clenching on dental cotton rollers, and during maximal mouth opening using BioEMG III (BioResearch Associates, Inc. Milwaukee, WI, USA). The IOL Master 500 (Carl Zeiss Meditec, Jena, Germany) was used to examine the eyeball length. Statistical analysis showed significant positive correlations during mouth opening in both groups with open and closed eyes. Results A greater number of correlations between the analyzed variables was observed in emmetropic women. In almost all cases, the longer axial eye length was associated with an increase in the bioelectrical activity of the analyzed muscles. Significant correlations were most often observed within the masseter and digastric muscles during the maximum mouth opening and at rest. Conclusion There is a relationship between the bioelectrical activity of the masticatory muscles and the axial length of the eyeball on the same side.

The Acute Influence of Whole-Body Cryotherapy on Electromyographic Signals and Jumping Tasks

Whole-body cryotherapy (WBC) is a popular treatment in prevention as well as post-injury therapy. The parameter used to assess the risk of injury is the ability of the human body to absorb and recover energy (elasticity). Therefore, this study aimed to assess the impact of whole-body cryotherapy (WBC) at 1 and 3 min intervals on the bioelectric activity of lower-limb muscles and countermovement jumps (CMJs) using trained subjects. A total of 24 individuals participated in the study. The mean age of the study group was 27.9 ± 7.9 years, mean body weight was 77.9 ± 8.8 kg, and mean body height was equal to 181 ± 6 cm. The training routine included 2–4 training sessions per week that lasted for at least 2 h at a time (mainly football). Along with the surface electromyography (sEMG) test of the rectus femoris, the BTS G-Sensor inertia measurement device was applied. After three minutes of WBC, a 6% difference in take-off force was noted, with a 7% (p &lt; 0.04) decrease in elasticity. In the bioelectrical activity of the rectus femoris after MVC normalization, differences (p &lt; 0.05) were noted 3 min after WBC. In this conducted study, a reduction in flexibility of the lower-limb muscle groups in the CMJ task was noted after 3 min of WBC.

The use of electromyography in the diagnosis and treatment of anal sphincter dysfunctions

Proper function of the anal sphincters largely depends on the integrity and efficiency of neural structures involved in controlling the maintaining stool and gas continence and compliant with the physiology and an individual’s will to empty the intestines. Nervous system disorders and injuries disrupt the bioelectrical activity of anal sphincters, the evaluation of which is important for both the treatment process and its outcomes. Electromyography, which is the only objective approach for assessing resting tone, the ability to maintain sphincter contraction and EMG biofeedback therapy, is the method of choice for assessing the bioelectrical activity of muscles. Electromyographic data significantly accelerate the diagnostic process and effective treatment implementation. If neurogenic aetiology of sphincter disorders is found, it is necessary to implement the rehabilitation process. The therapeutic approaches for neurogenic bowel dysfunction and stool or gas incontinence mainly include sphincter electrostimulation and/or biofeedback exercises, performed by patients at home, after training in the doctor’s office. The course of rehabilitation should be monitored as part of periodic follow-up EMGs.

Thigh Muscle Activation After a Home Exercise Program in Knee Osteoarthritis Patients

Aims: To evaluate changes in the bioelectrical activity of thigh muscles in concentric and eccentric movements of a sit-to-stand test in women with knee osteoarthritis after a preoperative home exercise program (HEP). Secondly, to compare patients with healthy controls. Methods: Seventeen women with knee osteoarthritis and ten healthy controls participated. The bioelectrical activity of thigh muscles during sit-to-stand test and isometric maximal voluntary contraction force of leg extensor muscles were measured. Results: Post-HEP, the knee osteoarthritis group demonstrated lower bioelectrical activity of antagonist muscles in the concentric and eccentric movements, and reduced asymmetry in muscle activation between limbs. Poorer results were noted compared to controls pre-and post-HEP. Conclusions: In knee osteoarthritis patients, the bioelectrical activity of thigh muscles during the sit-to-stand test improves after eight weeks of preoperative HEP. Preoperative HEP reduces co-activation of thigh muscles and activation asymmetry between limbs in concentric and eccentric movements of a sit-to-stand task.

Analysis of Upper Limbs Target-Reaching Movement and Muscle Co-Activation in Patients with First Time Stroke for Rehabilitation Progress Monitoring

In this paper, the authors analysed changes occurring during the rehabilitation processes in patients after early stroke based on analysis of their upper limbs’ target-reaching movement and muscle co-activation. Ischemic stroke often results in reduced mobility of the upper extremities and frequently is a cause for long-term disability. The ever-developing technology of 3D movement analysis and miniaturisation of equipment for testing the bioelectrical activity of muscles can help to assess the progress of rehabilitation. The aim of this study was to examine the use of analysis of target-reaching movement indicators and muscle co-activation for diagnosing the rehabilitation process in post-stroke patients. Twenty ischemic stroke patients in the early post-stroke phase (up to three months after the stroke), and twenty healthy subjects (the control group) took part in the experiments. The novel approach of the proposed research proved the usefulness of this approach in the diagnosis of the rehabilitation efficiency of rehabilitation in early post-stroke phase patients.

ФУНКЦИОНАЛЬНЫЕ ОСОБЕННОСТИ ЖЕВАТЕЛЬНОЙ МУСКУЛАТУРЫ У ДЕТЕЙ С ФИЗИОЛОГИЧЕСКОЙ ОККЛЮЗИЕЙ

The influence of sexual dimorphism on the functional features of chewing muscles in children may become a prerequisite for differences in the timing and methods of examining the functional state of chewing muscles, to various options for choosing techniques and preventing dentate abnormalities. Materials and methods. During the work study, 38 children aged 6 to 12 years with a physiological occlusion were examined. Evaluation of the bioelectric activity of temporal and sublingual muscles was carried out using superficial electromyography, the Chewing General sample, and the evaluation of the tone of the chewing muscles proper was carried out using the Mioton-3C device. Results. When comparing the tone of the chewing muscles and gender, it was not possible to establish statistically significant differences. When assessing all indicators of bioelectric conductivity of temporal and sublingual muscles of boys and girls, it was not possible to establish statistically significant differences. Conclusions. No relationship was identified between sexual dimorphism and functional features of chewing muscle in children with physiological occlusion at a given sample size. This may indicate the possibility of using the same choice of technique and prevention of tooth anomalies in boys and girls of this age group

The role of elastic bands (kinesiotapes) in complex therapy of patients with temporomandibular joint osteoarthrosis

Introduction. Temporomandibular joint (TMJ) arthrosis is a chronic disease, characterized by dystrophic and degenerative changes in TMJ with aseptic inflammatory process. The prevelence of TMJ arthrosis in patients with a history of other TMJ disorders varies between 32-39 % of cases. Complex treatment of TMJ arthrosis includes pharmacotherapy, physiotherapy, exercise therapy for TMJ and massage of the masticatory muscles, manual therapy, prosthodontics, but these treatment methods are not always lead to a desired result.The aim of the study is to improve the traditional treament method of patients suffering from TMJ arthrosis by using elastic tapes (kinesiotapes).Materials and methods. 68 patients were examined at the «Galaxy» Beauty Institute Clinic (St. Petersburg) and FSBEI HE SamSMU MOH Russia (Samara). Comparison group of patients was prescribed pharmacotherapy, exercise therapy for TMJ and massage of masticatory muscles, while for the main group of patients the same therapy was enhanced by elastic bands. The effectiveness of therapy was evaluated using a visual-analog pain scale (VAS), mouth opening width and electromyography of the masticatory muscles.Results. Noticeable positive effect in the main group of patients was observed on the 21th day of treatment. By this time patients noticed significant decrease in pain intensity from 8,77±0,8 to 5,19±0,5 (Z1-4=-5,88; p1-4=0,0015) points as well as increase in mouth opening width from 21-23 to 33-35 mm. Similar changes in the comparison group of patients were achieved only by the beginning of fifth week of treatment (Z1-6=-5,58; p1-6=0,0015). The range of mouth opening width increased from 21-23 to 27-29 mm. Amplitude of masticatory muscles biopotentials in maximum intercuspation in patients of the main group almost approached to the normal results by the beginning of the fourth week. In patients of the comparison group the amplitude of masticatory muscles biopotentials remained reduced even by the end of observations (42 day of the study).Conclusion. Thus, the combination of elastic bands applications with conventional treatment methods of TMJ arthrosis greatly increases the effectiveness of therapy and allows to relief pain and normalize bioelectric activity of masticatory muscles in a relatively short time. Due to the simplicity of elastic bands application it is possible to teach patients the technique of self-applying bands and recommend to use them as a prevention of relapse of TMJ arthrosis.

Functional interaction of chewing muscles in children with dentoalveolar system anomalies

Relevance. The focus of modern dental treatment not only on the elimination of aesthetic, but also functional disorders requires an understanding of the functional conjugation of the chewing muscles, the possibility of interprognosis of parameters. Objective. Assess the functional relationship between the tone of the chewing muscles proper and the bioelectric activity of the temporal and sublingual muscle groups in children with anomalies of the dentoalveolar system. Materials and Methods. The study involved 36 patients of Childrens Clinical Dental Clinic No. 2 of Voronezh, aged 6 to 12 years, who had not previously received orthodontic treatment and had distal occlusion anomalies. Evaluation of the bioelectric activity of temporal and sublingual muscles was carried out using surface electromyography on the Electromyograph Dental apparatus (Taganrog, Russia), the Chewing General sample. Evaluation of the tone of the chewing muscles proper was carried out using the Mioton-3C device in a state of physiological rest of the lower jaw. Statistical processing was carried out using Microsoft Excel, version 7.0 and the statistical programs SPSS Statistics 21 and STATISTICA 7. Results and Discussion. Correlation analysis revealed the presence of 4 weak positive, 2 weak negative, 14 moderate positive, 3 moderate negative, and 1 noticeable positive correlation between the tone of the right chewing muscle proper and the parameters of the bioelectric activity of the right and left temporal and sublingual muscles. Correlation analysis revealed the presence of 5 weak positive, 7 weak negative, 9 moderate negative correlations between the tone of the left chewing muscle proper and the parameters of bioelectric activity of the right and left temporal and sublingual muscles. Conclusion. A greater effect of the tone of the right chewing muscle on the bioelectric activity of temporal and sublingual muscles was found compared to the tone of the left chewing muscle itself. 27 equations have been derived that can be used as predictive models for calculating the tone of right and left chewing muscles proper depending on the indicators of bioelectric activity of temporal and sublingual muscles.

Электромиографическое исследование биоэлектрической активности мышц нижних конечностей у пациентов с дегенеративным стенозом, осложненным синдромом нейрогенной перемежающейся хромоты

Статья посвящена исследованию и оценке функционального состояния нервно-мышечного аппарата методом интерференционной электромиографии пациентов с дегенеративным стенозом поясничного отдела позвоночника, осложненного нейрогенной перемежающейся хромотой. Полученные данные свидетельствуют о наличии неблагоприятных признаков в организации биоэлектрической активности мышц у больных со стенозами на уровне поясничного отдела позвоночника как в состоянии покоя, так и после специфической нагрузки. Снижение биоэлектрической активности мышц после нагрузочного теста связано с замедлением, а также частичной или полной блокадой проведения возбуждения в разных структурных элементах двигательных единиц, что подтверждают данные настоящего исследования.

СРАВНИТЕЛЬНАЯ ОЦЕНКА ПОКАЗАТЕЛЕЙ БИОЭЛЕКТРИЧЕСКОЙ АКТИВНОСТИ МЫШЦ У ПАЦИЕНТОВ СО СЪЕМНЫМИ ПОКРЫВНЫМИ ПРОТЕЗАМИ С ОПОРОЙ НА ИМПЛАНТАТЫ ПРИ ПОЛЬЗОВАНИИ В ТЕЧЕНИЕ 12 МЕСЯЦЕВ

Subject. A comparative assessment of the state of the stomatognathic system on the example of the bioelectrical activity of temporal and masticatory muscles in patients who used removable implant-supported overdentures with bar fixation system, made by two different methods: traditional and using digital methods of treatment planning and manufacturing was carried out.&#x0D; Objectives. To compare the changes of bioelectrical activity of temporal and masticatory muscles in patients with removable implant-supported overdentures made by two different methods: traditional and digital, who used dentures for a long time (12 months).&#x0D; Methods. Bioelectrical activity and symmetry of temporal and masseter muscles were investigated clinically by surface electromyography. Electromyography was performed in five probes: Rest, Light CO, Natural Swallowing, Maximal Volitional Clench (MVC) and Clench on Cotton Rolls (MVCCR).&#x0D; Results. In patients using overdentures produced in traditional way, no normal values of muscle activity were observed in any of the probes at the end of the study. In patients who used overdentures, made with the use of digital technologies, we noted a decrease of bioactivity of the muscles in the probes of Rest and Light CO, and an increase of biopotentials in the probes of MVC and MVCCR. The values obtained at the end of the study were characterized as normal or acceptable.&#x0D; Conclusions. The application of a digital method of treatment planning and fabrication of removable implant-supported overdentures with a bar fixation system allows to achieve more physiological values of temporal and masticatory muscles biopotentials, which can be interpreted as recovery of the functional integrity of the stomatognathic system.

The influence of cervical spine rehabilitation on bioelectrical activity (sEMG) of cervical and masticatory system muscles.

BackgroundCoexistence of temporomandibular joint discomfort along with cervical spine disorders is quite common, and is associated with many limitations and adverse symptoms for the patient. Both diagnostics and treatment of these ailments are difficult, and in many cases, the effects of therapy are not satisfactory. This study assessed the impact of a 3-week neck-only rehabilitation programme without direct intervention in the craniofacial area on the bioelectric activity of both the cervical spine and muscles in the craniofacial area among patients with idiopathic neck pain who do not report TMJ pain.DesignA parallel group trial with follow-up; Setting: Rehabilitation Clinic.MethodsTwenty five patients experiencing idiopathic neck pain underwent the 3-week rehabilitation programme. Thirty five age-matched subjects with no cervical spine and temporomandibular joint (TMJ) dysfunctions were control group. At baseline and after 3 weeks the cervical and craniofacial area muscles’ bioelectrical activity (sEMG) was evaluated.ResultsIn the experimental group during cervical flexion, a significant decrease of sEMG amplitude was noted in the right (mean 25.1 μV; 95% CI: 21.5–28.6 vs mean 16.8 μV; 95% CI: 13.8–19.7) and left (mean 25.9 μV; 95% CI: 21.7–30.0 vs mean 17.2 μV; 95% CI: 13.6–20.7) Sternocleidomastoid as well as a significant increase in sEMG amplitude of the right (mean 11.1 μV; 95% CI: 7.9–14.2 vs mean 15.7 μV; 95% CI: 12.1–19.2) and left (mean 15.3 μV; 95% CI: 11.9–18.6 vs mean 20.2 μV; 95% CI: 15.7–24.2) Upper Trapezius muscles. In the experimental group, after therapy right and left Sternocleidomastoid, Temporalis Anterior and Masseter muscles presented lower fatigue levels.ConclusionsThree weeks of rehabilitation without any therapeutic intervention in temporomandibular joint significantly decreased the bioelectrical activity of the neck and craniofacial muscles while improving the muscle pattern of coactivation in participants with idiopathic neck pain who do not report temporomandibular joint pain. These observations could be helpful in the physiotherapeutic treatment of neck and craniofacial area dysfunctions.Trial registrationID ISRCTN14511735—retrospectively registered.