title: Reliability of a portable device for the detection of sleep bruxism.
abstract: OBJECTIVE
  The aim of the study was to assess the repeatability in detecting sleep bruxism (SB) episodes by combined surface electromyography and heart rate (HR) signals recorded by a compact portable device (Bruxoff®). SB episodes are preceded by a sudden HR change. Thus, HR detection increases the precision of automatic detection of SB.
  
  
  METHODS
  Ten healthy subjects (five women and five men; 30.2 ± 11.02 years) were selected for the study. Rhythmic masseter muscle activities, constituting the basic pattern of SB, were detected during three nights of recording during three different weeks with the Bruxoff device.
  
  
  RESULTS
  The two-way ANOVA was not significant for SB episodes per night, SB episodes per hour, and heart frequency: no significant differences were observed during the three different nights of recording for each of the abovementioned variables (P > 0.05). The intraclass correlation coefficient showed a good reproducibility for SB episodes per night (69 %), SB per hour (74 %), and heart frequency (82 %). A poor reproducibility was revealed for the number of masseter contractions (53 %). The Pearson analysis showed the absence of a significant correlation between the number of masseter contractions per night and the number of SB episodes per night (r = -0.02, P = 0.91).
  
  
  CONCLUSIONS
  The Bruxoff device showed a good reproducibility of measurements of sleep bruxism episodes over time.
  
  
  CONCLUSIONS
  These findings are important in the light of the need for simple and reliable portable devices for the diagnosis of SB both in the clinical and research settings.
authors.affiliation: Department of Surgical Sciences, Specialization School of Orthodontics, Dental School, University of Torino, Via Nizza 230, 10100, Torino, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Deregibus
authors.forename: Tommaso
authors.initials: T
authors.lastname: Castroflorio
authors.forename: Andrea
authors.initials: A
authors.lastname: Bargellini
authors.forename: Cesare
authors.initials: C
authors.lastname: Debernardi
mesh_terms: D000328:Adult; D004576:Electromyography; D004864:Equipment and Supplies; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D020186:Sleep Bruxism / Q000175:diagnosis* / Q000503:physiopathology; D055815:Young Adult