title: Muscle pain in the head: overlap between temporomandibular disorders and tension-type headaches.
abstract: OBJECTIVE
  A variety of painful problems can affect the muscles in the head and face. Both temporomandibular disorders and tension-type headaches are believed to have a significant contribution from the skeletal muscles and have several clinical features in common. It still unclear, however, to what extent these two prevalent disorders are separate entities or have similar pathophysiological background.
  
  
  RESULTS
  There is now reasonably good evidence that myofascial temporomandibular disorder patients are more likely to have a tension-type headache problem and vice versa, but the overlap is not complete. Studies have documented similarities regarding sensitization of the nociceptive pathways, dysfunction of the endogenous pain modulatory systems as well as contributing genetic factors, but there are also a number of distinct differences between temporomandibular disorders and tension-type headaches that need to be considered.
  
  
  CONCLUSIONS
  Using the current classification systems, myofascial temporomandibular disorder pain and tension-type headache disorders do overlap and appear to share many of the same pathophysiological mechanisms, but it would be premature to consider them as identical entities since the importance of, for example, the affected muscles and associated function and genetic background needs to be established. Orofacial pain and headache specialists should collaborate to further develop diagnostic procedures and management strategies of temporomandibular disorders and tension-type headaches.
authors.affiliation: Department of Clinical Oral Physiology, School of Dentistry, University of Aarhus, Denmark. psvensson@odont.au.dk
authors.forename: Peter
authors.initials: P
authors.lastname: Svensson
mesh_terms: D000344:Afferent Pathways / Q000503:physiopathology; D001921:Brain / Q000503:physiopathology; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D009334:Neck Muscles / Q000294:innervation / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology; D009619:Nociceptors / Q000503:physiopathology; D013704:Temporomandibular Joint / Q000294:innervation / Q000503:physiopathology*; D013705:Temporomandibular Joint Disorders / Q000235:genetics / Q000503:physiopathology*; D018781:Tension-Type Headache / Q000235:genetics / Q000503:physiopathology*