title: The use of botulinum toxin for the treatment of temporomandibular disorders: preliminary findings.
abstract: OBJECTIVE
  The aim of this study was to evaluate the response of patients with temporomandibular disorders to Botulinum toxin A (BTX-A) therapy.
  
  
  METHODS
  The 15 subjects enrolled in this uncontrolled study were diagnostically categorized and treated with 150 units of BTX-A. Both masseter muscles received 50 units each under eletromyographic (EMG) guidance. Similarly, both temporalis muscles were injected with 25 units each. Subjects were assessed at 2-week intervals for 8 weeks. Outcome measures included subjective pain by visual analog scale (VAS), measurement of bite force, interincisal opening, tenderness to palpation, and a functional index based on multiple VAS.
  
  
  RESULTS
  All mean outcome measures, with the exception of bite force, showed a significant (P = .05) difference between the preinjection assessment and the four follow-up assessments. No side effects were reported.
  
  
  CONCLUSIONS
  BTX-A injections produced a statistically significant improvement in four of five measured outcomes, specifically pain, function, mouth opening, and tenderness. No statistically significant changes were found in mean maximum voluntary contraction or in paired correlation of factors such as age, sex, diagnosis, depression index, or time of onset.
authors.affiliation: Faculty of Dentistry, University of Toronto, Ontario, Canada. brian@max-facial.com
authors.forename: B
authors.initials: B
authors.lastname: Freund
authors.forename: M
authors.initials: M
authors.lastname: Schwartz
authors.forename: J M
authors.initials: JM
authors.lastname: Symington
mesh_terms: D000279:Administration, Cutaneous; D000293:Adolescent; D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000008:administration & dosage*; D011446:Prospective Studies; D013705:Temporomandibular Joint Disorders / Q000188:drug therapy* / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A