Temporomandibular Joint Syndrome, Temporomandibular disorder(s) (TMD) or temporomandibular joint (TMJ) syndrome is the most common cause of facial pain after toothache. In the past, many physicians called this condition TMJ disease or TMJ syndrome. The term temporomandibular disorder (TMD) is the preferred term according to the American Academy of Orofacial Pain (AAOP) and most other groups who sponsor studies into its origins and treatment. Interestingly, the National Institute of Dental and Craniofacial Research (NIDCR) puts TMJ and TMD together and refers to them as temporomandibular joint disorder (TMJD) on its Web site. The authors preferentially use the term temporomandibular disorder (TMD) in this article.
Two widely used classification schemes exist. The AAOP classification divides TMD broadly into 2 syndromes: (1) muscle-related TMD (myogenous TMD), sometimes this is called TMD secondary to myofacial pain and dysfunction (MPD), and (2) joint-related (arthrogenous) TMD, that is TMD secondary to true articular disease. The 2 types can be present at the same time, making diagnosis and treatment more challenging.
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Temporomandibular Joint Syndrome – – The TMJ Association – http://www.tmj.org/site/