title: Effects of botulinum toxin on jaw motor events during sleep in sleep bruxism patients: a polysomnographic evaluation.
abstract: OBJECTIVE
  To investigate the effects of botulinum toxin type A (BoNT-A) injection on jaw motor episodes during sleep in patients with or without orofacial pain who did not respond to oral splint treatment.
  
  
  METHODS
  Twenty subjects with a clinical diagnosis of SB completed this study. Ten subjects received bilateral BoNT-A injections (25 U per muscle) into the masseter muscles only (group A), and the other 10 received the injections into both the masseter and temporalis muscles (group B). Video-polysomnographic (vPSG) recordings were made before and at 4 weeks after injection. Rhythmic masticatory muscle activity (RMMA) and orofacial activity (OFA) were scored and analyzed for several parameters (e.g., frequency of episodes, bursts per episode, episode duration). The peak amplitude of electromyographic (EMG) activity in the two muscles was also measured.
  
  
  RESULTS
  BoNT-A injection did not reduce the frequency, number of bursts, or duration for RMMA episodes in the two groups. The injection decreased the peak amplitude of EMG burst of RMMA episodes in the injected muscles (p < 0.001, repeated measure ANOVA) in both groups. At 4 weeks after injection, 9 subjects self-reported reduction of tooth grinding and 18 subjects self-reported reduction of morning jaw stiffness.
  
  
  CONCLUSIONS
  A single BoNT-A injection is an effective strategy for controlling SB for at least a month. It reduces the intensity rather than the generation of the contraction in jaw-closing muscles. Future investigations on the efficacy and safety in larger samples over a longer follow-up period are needed before establishing management strategies for SB with BoNT-A.
  
  
  BACKGROUND
  Shim YJ; Lee MK; Kato T; Park HU; Heo K; Kim ST. Effects of botulinum toxin on jaw motor events during sleep in sleep bruxism patients: a polysomnographic evaluation.
authors.affiliation: Department of Orofacial Pain and Oral Medicine, Daejeon Dental Hospital, College of Dentistry, Wonkwang University, Daejeon, Korea.
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Shim
authors.affiliation: Department of Neurology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Moon Kyu
authors.initials: MK
authors.lastname: Lee
authors.affiliation: Department of Oral Anatomy and Neurobiology, Osaka University Graduate School of Dentistry, Osaka, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kato
authors.affiliation: Department of Dentistry, Korea Army Training Center District Hospital, Nonsan, Korea.
authors.forename: Hyung Uk
authors.initials: HU
authors.lastname: Park
authors.affiliation: Department of Neurology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyoung
authors.initials: K
authors.lastname: Heo
authors.affiliation: Department of Orofacial Pain and Oral Medicine, Yonsei University College of Dentistry, Seoul, Korea.
authors.forename: Seong Taek
authors.initials: ST
authors.lastname: Kim
mesh_terms: D000328:Adult; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D004576:Electromyography; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008406:Masseter Muscle / Q000187:drug effects / Q000502:physiology; D008410:Masticatory Muscles / Q000187:drug effects / Q000502:physiology*; D009068:Movement / Q000187:drug effects / Q000502:physiology; D017286:Polysomnography; D020186:Sleep Bruxism / Q000188:drug therapy*; D013703:Temporal Muscle / Q000187:drug effects / Q000502:physiology; D014741:Video Recording; D055815:Young Adult
chemical_list: D019274:Botulinum Toxins, Type A
keywords: Sleep bruxism; botulinum toxin; jaw motor activity; masticatory muscle pain; polysomnography; rhythmic masticatory muscle activity