Botulinumtoxin A as a Treatment for Myalgia and Myofacial Pain in Patient With Temporomandibulardisorders

Inclusion Criteria: * Has given a written consent * Diagnose of myalgia, myofacial pain or myofascial pain with referred pain according * Average pain due to NRS ≥ 3 for more than three months * Palpationpain in masseter or temporalis. * Eventual treatment for orofacial pain \> three months ago. * Adequate contraceptives and a negative pregnancy test. Patients will still be included even if they have one or more co-diagnoses * Discdisplacement with or without reduction * Degenerative joint disease * Arthralgia Exclusion Criteria: * Treatment with BTX during the last 12 months * Treatment for orofacial pain within the last 3 months. * Systemic inflammatory diseases (rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis) * Widespread pain e.g., fibromyalgia * Neuropathic pain * Neurologic disease (myasthenia gravis) * Pain of dental origin * Use of muscle relaxants, or aminoglycoside antibiotics * Pregnancy or nursing * Hypersensitivity to BTX * Neuropsychiatric conditions. * Difficulties understanding the Swedish language