Premium
Automated analysis for portable EMG recording of nocturnal masseter activity in bruxers
Author(s) -
GALLO L. M.,
ROMPRÉ P.,
LAVIGNE G.,
PALLA S.
Publication year - 2002
Publication title -
journal of oral rehabilitation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 93
eISSN - 1365-2842
pISSN - 0305-182X
DOI - 10.1046/j.1365-2842.2002.01026_3.x
Subject(s) - sleep bruxism , masseter muscle , electromyography , asymptomatic , medicine , audiology , dentistry , physical medicine and rehabilitation
Facial pain of patients with craniomandibular disorders might be caused by muscle overload. In a former study (Gallo et al ., 1999) we collected data on masseter EMG of healthy subjects during sleep by means of portable recorders (integration time of 500 ms). The automated analysis of the tracings yielded the normal range of activity in the natural environment. For this study, we focused on the analysis of the distribution of masseter activity in bruxers by means of the same automated system used for asymptomatic subjects. For this purpose, data from single masseter channels of polysomnographic recordings of 10 bruxers and 10 controls were reformatted as if they had been recorded by means of the portable devices. The signals were analysed for number, amplitude and duration of contraction episodes (signal portions above a threshold which could contain subthreshold portions shorter than the standby time of 5 s). The signal amplitude was expressed in percentage of the amplitude at maximum voluntary contraction (%MVC). In the bruxers, 166·8 ± 48·5 contraction episodes per night, i.e. 20·4 ± 5·7 h−1, with a net duration of 8·4 ± 2·4 s and an integral of the amplitude over time of 191·6 ± 74·0 %MVCs were found (controls: 96·5 ± 39, 12·9 ± 3·5, 4·7 ± 1·2 s and 99·1 ± 28·0 %MVCs, respectively) . For these parameters there was a statistically significant difference between the two groups ( t ‐test, P < 0·01). The distribution of all contraction episodes of all bruxers according to net duration and mean amplitude was shifted towards shorter episodes with a massive presence of episodes between 60 and 70% MVC, much higher than in controls.