title: Infield masticatory muscle activity in subjects with pain-related temporomandibular disorders diagnoses.
abstract: OBJECTIVE
  Pain-related temporomandibular disorders (TMDs) are the most prevalent conditions among TMDs. There is contrasting evidence available for association of pain-related TMD and masticatory muscle activity (MMA). The present investigation assesses the associations between MMA levels of masseter and temporalis muscles during awake and sleep among pain-related TMD diagnostic groups.
  
  
  METHODS
  The department of Oral Diagnostic Sciences, University at Buffalo. Twenty females and six males participated in this study.
  
  
  METHODS
  Using the diagnostic criteria for temporomandibular disorders (DC-TMDs), participants were diagnostically categorized. Subjects used a custom monitoring system, which recorded infield muscle activities. A factorial model tested for association between independent variable (muscle, time period, MMA level, and diagnostic group) effects and the logarithm of MMA. Greenhouse-Geisser test was used to determine any statistically significant associations (p≤0.003).
  
  
  RESULTS
  No statistically significant association was found between four-way, three-way, and two-way analyses. However, among the main effects, range of magnitudes was the only variable to be statistically significant. Although the data suggest a trend of increased masseter MMA in the pain-related TMD diagnoses group both during awake and sleep time periods, such observation is not maintained for the temporalis muscle. In addition, temporalis MMA was found to be higher in the pain-related TMD diagnoses group only at extreme activity levels (<25 and ≥80% ranges).
  
  
  CONCLUSIONS
  This data support the association between masticatory muscle hyperactivity and painful TMD conditions.
authors: Oral Diagnostic Sciences, University at Buffalo, Buffalo, NY, USA.
authors: S N
authors: SN
authors: Khawaja
authors: W
authors: W
authors: McCall
authors: R
authors: R
authors: Dunford
authors: J C
authors: JC
authors: Nickel
authors: L R
authors: LR
authors: Iwasaki
authors: H C
authors: HC
authors: Crow
authors: Y
authors: Y
authors: Gonzalez
mesh_terms: D000328:Adult; D018771:Arthralgia / Q000503:physiopathology; D001732:Bite Force; D004576:Electromyography / Q000379:methods; D005157:Facial Pain / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000503:physiopathology*; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000379:methods; D009129:Muscle Tonus / Q000502:physiology; D063806:Myalgia / Q000503:physiopathology; D012890:Sleep / Q000502:physiology; D013703:Temporal Muscle / Q000503:physiopathology*; D013705:Temporomandibular Joint Disorders / Q000145:classification / Q000503:physiopathology*; D014159:Transducers; D014851:Wakefulness / Q000502:physiology; D055815:Young Adult
keywords: bruxism; electromyography; masticatory muscles; pain; temporomandibular joint disorders