[EP-21] Individual differences in baseline signal at rest in an examination of sleep bruxism by using a wearable electromyographic device
[Abstract]
[Objective]
A baseline amplitude at rest has been utilized as a threshold for selecting waveform in electromyography (EMG) of masticatory muscle, while individual difference in baseline amplitude is concerned.
The aim of this study was to clarify the actual state of individual differences in the baseline of masseteric EMG using a wearable electromyographic device and to examine the influence of individual differences on sleep bruxism (SB) diagnosis.
[Method]
Masseteric EMG activities of 21 participants were recorded at home using a wearable EMG device (W-EMG, GC Co. Japan) with high resistance to external electric noise. A part of stable baseline for 5 seconds during awake state was selected. It was analyzed whether the results of SB diagnosis are different between the case utilizing baseline amplitude value of each subject as the standard and that uniformly utilizing the mean value in baseline amplitude of the 21 subjects.
In case number of episodes, i.e., a cluster of bursts of more than twice the baseline amplitude with a duration of 0.25 s or more, were 5.5 or more per hour, the subject was defined as a sleep bruxer.
[Results and Discussion]
The mean and standard deviation of the peak value of the baseline amplitude for all subjects (n=21) was 0.004995±0.000419mV.
As for SB assessment based on the individual baseline amplitude, the mean number of episodes/h was 7.37. Fifteen subjects were diagnosed as a bruxer and 6 subjects were diagnosed as a non-bruxer.
On the other hand, when uniformly utilizing the mean value, i.e., 0.005 mV, the mean number of episodes/h was 7.30, and 16 subjects were diagnosed as a bruxer and 5 subjects were diagnosed as a non-bruxer.
Correlation coefficient between the number of episodes/h utilizing the individual baseline amplitude and that utilizing the uniform value of 0.005 mV was 0.987.
The accuracy of SB diagnosis based on the uniform value of 0.005 mV compared to that based on individual baseline amplitude was 0.984.
The baseline amplitude of the W-EMG was stable with little individual differences, and it was suggested that individual differences in baseline have an extremely small effect on SB diagnosis.
[Objective]
A baseline amplitude at rest has been utilized as a threshold for selecting waveform in electromyography (EMG) of masticatory muscle, while individual difference in baseline amplitude is concerned.
The aim of this study was to clarify the actual state of individual differences in the baseline of masseteric EMG using a wearable electromyographic device and to examine the influence of individual differences on sleep bruxism (SB) diagnosis.
[Method]
Masseteric EMG activities of 21 participants were recorded at home using a wearable EMG device (W-EMG, GC Co. Japan) with high resistance to external electric noise. A part of stable baseline for 5 seconds during awake state was selected. It was analyzed whether the results of SB diagnosis are different between the case utilizing baseline amplitude value of each subject as the standard and that uniformly utilizing the mean value in baseline amplitude of the 21 subjects.
In case number of episodes, i.e., a cluster of bursts of more than twice the baseline amplitude with a duration of 0.25 s or more, were 5.5 or more per hour, the subject was defined as a sleep bruxer.
[Results and Discussion]
The mean and standard deviation of the peak value of the baseline amplitude for all subjects (n=21) was 0.004995±0.000419mV.
As for SB assessment based on the individual baseline amplitude, the mean number of episodes/h was 7.37. Fifteen subjects were diagnosed as a bruxer and 6 subjects were diagnosed as a non-bruxer.
On the other hand, when uniformly utilizing the mean value, i.e., 0.005 mV, the mean number of episodes/h was 7.30, and 16 subjects were diagnosed as a bruxer and 5 subjects were diagnosed as a non-bruxer.
Correlation coefficient between the number of episodes/h utilizing the individual baseline amplitude and that utilizing the uniform value of 0.005 mV was 0.987.
The accuracy of SB diagnosis based on the uniform value of 0.005 mV compared to that based on individual baseline amplitude was 0.984.
The baseline amplitude of the W-EMG was stable with little individual differences, and it was suggested that individual differences in baseline have an extremely small effect on SB diagnosis.