title: Females with sleep bruxism show lower theta and alpha electroencephalographic activity irrespective of transient morning masticatory muscle pain.
abstract: OBJECTIVE
  To investigate the hypothesis that the presence of transient morning masticatory muscle pain in young, healthy sleep bruxers (SBr) is associated with sex-related differences in sleep electroencephalographic (EEG) activity.
  
  
  METHODS
  Data on morning masticatory muscle pain and sleep variables were obtained from visual analog scales and a second night of polysomnographic recordings. Nineteen normal control (CTRL) subjects were age- and sex-matched to 62 tooth-grinding SBr. Differences in sleep macrostructure (stage distribution and duration, number of sleep-stage shifts), number of rhythmic masticatory muscle activity (RMMA) events÷ hour, and EEG activity were analyzed blind to subject status. The influence of pain and gender in SBr and CTRL subjects was assessed with the Fisher's exact test, Mann-Whitney U test, two-sample t test, and analysis of variance (ANOVA).
  
  
  RESULTS
  Low-intensity morning transient orofacial pain was reported by 71% of SBr, with no sex difference. RMMA event frequency was higher in SB than CTRL subjects (4.5÷hour vs 1.3÷hour; P < .001). SBr had fewer sleep-stage shifts, irrespective of sex or pain status. Female SBr had significantly lower theta and alpha EEG activity compared to female CTRL subjects (P = .03), irrespective of pain.
  
  
  CONCLUSIONS
  Female SBr had lower theta and alpha EEG activity irrespective of transient morning pain.
authors: Tokushima University Hospital, Japan.
authors: Susumu
authors: S
authors: Abe
authors: Maria Clotilde
authors: MC
authors: Carra
authors: Nelly T
authors: NT
authors: Huynh
authors: Pierre H
authors: PH
authors: Rompré
authors: Gilles J
authors: GJ
authors: Lavigne
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001143:Arousal; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002940:Circadian Rhythm; D004569:Electroencephalography; D005157:Facial Pain / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008410:Masticatory Muscles / Q000503:physiopathology*; D010147:Pain Measurement; D017286:Polysomnography; D012737:Sex Factors; D020186:Sleep Bruxism / Q000150:complications* / Q000503:physiopathology*; D012894:Sleep Stages; D018709:Statistics, Nonparametric; D055815:Young Adult