The Effect of Botulinum Toxin A on Headache Attributed to TMD
Condition: Secondary Headache Disorder
MeSH terms: Headache Disorders; Headache Disorders, Secondary; Headache
Study type: Interventional
Phase: Early Phase 1

Summary: 
      This study will evaluate the effect of of botulinum toxin on the treatment of Headache
      Attributed to TMD.
    

Detailed description: 
      Temporomandibular Disorders (TMD) is a collective term, embracing a number of clinical
      problems that involve the masticatory muscles, the temporomandibular joint (TMJ) and the
      associated structures. The prime manifestation consists of pain of a persistent, recurring,
      or chronic nature . Pain-related TMD can affect the individual's daily activities,
      psychosocial functioning, and quality of life . The prevalence of TMD is about 10 % in the
      general population, making it the second most common musculoskeletal condition, after chronic
      lower back pain, that results in pain and disability . It has been estimated that the annual
      TMD management cost in the USA, excluding diagnostic imaging, in the last decade was
      approximately $4 billion.

      The pathophysiology of pain-related TMD is poorly understood. However, multiple risk factors
      have been identified, such as, gender, pain during jaw function and palpation, oral
      parafunctions, other pain conditions, pain sensitivity and psychosocial characteristics.
      Because of its multifactorial nature, a multimodal conservative treatment approach is
      recommended, including patient education, behavioral management, physical therapy,
      pharmacotherapy, and occlusal splints.

      Among the pain-related TMD conditions are "Headaches Attributed to TMD". This diagnosis has
      replaced "Headaches or facial pain attributed to Temporomandibular Joint (TMJ) disorder"
      described in the International Classification of Headache Disorders II (ICHD-2). It is
      characterized by pain in the temple area secondary to pain-related TMD that is modified by
      function and parafunction affected by jaw movement, function, or parafunction.

      In general, headache treatment is either abortive or prophylactic. Abortive treatment manages
      acute headache and prophylactic treatment aims to reduce the frequency and severity of the
      attacks. Intramuscular injections with Botulinum Toxin (BTX) are used in the prophylactic
      treatment of migraine and tension type headaches. The mechanisms by which the analgesic
      effects of BTX are mediated are not fully understood. One mechanism is the inhibition of
      neurogenic inflammation by blocking neurotransmitter release from sensitized nociceptors,
      thus reducing peripheral sensitization. In vitro, BTX has been found to inhibit Calcitonin
      Gene-Related Peptide (CGRP), and BTX reduces the vascular response to algogenic substances
      such as capsaicin applied to human skin. Other potential analgesic mechanisms include
      retrograde transport of BTX by sensory neurons and inhibition of neurotransmitter release by
      their central terminals.

      In recent years, BTX has also been used in the treatment of myogenous-TMD with mixed results.
      Two randomized controlled trials (RCTs) showed therapeutic benefits of BTX in the management
      of myogenous -TMD, while another 3 RCTs reported no significant effect of BTX in chronic
      myogenous -TMD pain. Varying patient samples, methodologies, and sample sizes may explain the
      differences. Additionally, the results have been compromised by poor methodologies, such as
      insufficiently powered clinical trials, and open-labeled studies. More recently, a systematic
      review of randomized controlled trials concluded that no consensus could be reached on the
      therapeutic benefit of BTX on TMD. More so, no trial on the effectiveness of BTX on the
      prophylactic treatment of headaches attributed to TMD has been reported to date.

      The purpose of this study is to determine the effectiveness of Botulinum toxin - A in the
      management of headaches attributed to TMD.

      Study Design The study will be carried out in the clinics of TMD and Orofacial Pain, School
      of Dental Medicine, University at Buffalo. A prospective open label design will be used to
      assess the effectiveness of BTX in the management of Headaches Attributed to TMD.

      Recruitment will be done through advertising throughout the clinic and the community.
    

Intervention name(s): Botulinum Toxin type A
Intervention type(s): Drug
Intervention description(s): All the participants meeting the inclusion criteria will be seen for a total of 4 visits and 3 phone interviews. Participants will complete a set of self-reporting questionnaires, assessing the disability associated with Headaches Attributed to TMD, and other pain-related TMD diagnoses, the impact of headaches on the quality of life, and psychosocial distress questionnaires.
In addition, they will undergo 3 cycles of treatment, each 12 weeks apart.
Other intervention name(s): Botox
Intervention MeSH terms: Botulinum Toxins; Botulinum Toxins, Type A; abobotulinumtoxinA
Intervention model: Single Group Assignment
Intervention model description: Open Label.
Masking: None (Open Label)
Primary purpose: Treatment