Actual state of the diurnal masseteric electromyogram: Differences between awareness and non-awareness of awake bruxism.

Purpose: This study aimed to elucidate the relationship between diurnal masseter muscle activity and awareness of diurnal awake bruxism (d-AB) by conducting a comparative analysis of electromyographic (EMG) data from individuals with and without awareness of diurnal awake bruxism (d-AB), utilizing EMG data gathered from multiple subjects.

Methods: Unilateral masseter electromyography (EMG) recordings were performed during the daytime using an ultraminiature wearable EMG device. A total of 119 participants (59 with awareness of diurnal tooth clenching [d-TC] and 60 without awareness of d-TC) were included.

Frequency distribution of the number and amplitude of electromyographic waveforms of the masseter muscle during sleep in patients with a clinical diagnosis of sleep bruxism.

Objective: This study aimed to clarify frequency distribution of number and peak amplitude of electromyographic (EMG) waveforms of sleep bruxism (SB) in outpatients with clinical diagnosis of SB (probable bruxer: P-bruxer).

Methods: Subjects were 40 P-bruxers. Masseteric EMG during sleep was measured at home using a wearable EMG system.

Examination of the relationship between masseter muscle activity during sleep and wakefulness measured by using a wearable electromyographic device.

Purpose This study aimed to measure masseter muscle activity throughout the day in outpatients suspected of having awake bruxism (AB) and/or sleep bruxism (SB) and examine the relationship between AB and SB by comparing muscle activity during daytime wakefulness and nighttime sleep.Methods Fifty outpatients with suspected SB and/or AB participated in this study. A single-channel wearable electromyogram (EMG) device was used for EMG recording.

Validity of clinical diagnostic criteria for sleep bruxism by comparison with a reference standard using masseteric electromyogram obtained with an ultraminiature electromyographic device.

Evaluation of sleep bruxism (SB) in clinical practice is currently conducted based on clinical findings, i.e., clinical diagnostic criteria consisting of medical interview, findings of tooth wear, and symptoms of temporomandibular joint (TMJ) and muscles.

Portable and wearable electromyographic devices for the assessment of sleep bruxism and awake bruxism: A literature review.

Objective: The current state of portable/wearable electromyographic (EMG) devices for assessment of bruxism was reviewed.

Methods: A search of full-text articles relevant to portable/wearable EMG devices capable of being used at home was performed. The data source used was MEDLINE via PubMed from January 1970 to July 2019.

Rhythm and amplitude of rhythmic masticatory muscle activity during sleep in bruxers - comparison with gum chewing.

Objectives: The aim of this study was to elucidate characteristics of rhythmic masticatory muscle activity (RMMA) during sleep by comparing masseteric EMG (electromyogram) activities of RMMA with gum chewing.

Method: The parts of five or more consecutive phasic bursts in RMMA of 23 bruxers were analyzed. Wilcoxon signed-rank test for matched pairs and Spearman's correlation coefficient by the rank test were used for statistical analysis.

Weak association between sleep bruxism and obstructive sleep apnea. A sleep laboratory study.

Purpose: No definitive associations or causal relationships have been determined between obstructive sleep apnea-hypopnea (OSAH) and sleep bruxism (SB). The purpose of this study was to investigate, in a population reporting awareness of both OSAH and SB, the associations between each specific breathing and jaw muscle event.

Methods: Polysomnography and audio-video data of 59 patients reporting concomitant OSAH and SB history were analyzed.

Temporal association between sleep apnea-hypopnea and sleep bruxism events.

There is some evidence suggesting that obstructive sleep apnea-hypopnea syndrome is concomitant with sleep bruxism. The aim of this study was to investigate the temporal association between sleep apnea-hypopnea events and sleep bruxism events. In an open observational study, data were gathered from 10 male subjects with confirmed obstructive sleep apnea-hypopnea syndrome and concomitant sleep bruxism.

Influence of motion and posture of the head on data obtained using the newly developed ultraminiature cordless bruxism measurement system.

Purpose: To elucidate the influence of motion and posture of head on the newly developed ultraminiature cordless bruxism measurement system (BMS), we examined masseteric electromyographic (EMG) data of BMS during turning-over movements in bed in comparison with those of a conventional polygraph system (PG).

Methods: Twelve healthy subjects lay on their back and then turned to the right (right turn, 90 degrees) and then to the left (left turn, 180 degrees). Maximum amplitudes and root mean square (RMS) values of EMG data were calculated during the phase of turning movements.

Condylar movements of temporomandibular disorder patients with intermittent lock: a pilot study.

The purpose of this study was to clarify which direction of the condylar path is advantageous for releasing TMJ intermittent lock. The subjects were ten patients with temporomandibular disorders (TMD) and intermittent lock caused by anterior displacement of disks without obvious medial or lateral displacement. The patients could not open their mouths fully in habitual opening but could open fully in an intentional winding opening with reduction of the anteriorly displaced disks (winding opening).

The influence of tissue blood flow volume on energy metabolism in masseter muscles.

This study investigated the energy metabolism of masseter muscles by 31P-Magnetic Resonance Spectroscopy (MRS) during increased blood flow induced by hot pack application to clarify the influence of changes in blood flow on muscle fatigue. Twelve healthy subjects with no history of muscle pain in the masticatory system participated in this study. The 31P-MRS measurements were performed before and after hot pack application and the ratio of phosphocreatine (PCr) acting as the energy source to reproduce ATP to beta-ATP, the PCr/beta-ATP ratio, was analyzed.