Definition of the Temporomandibular Joint
and Temporomandibular Joint Disorder
The temporomandibular joint (TMJ) is a freely moveable (diathrodial) articulation between the condyle of the mandible and the temporal bone. It is unique because it is a true synovial joint and, therefore, has much in common with the other synovial joints of the body. It does, however, possess certain unique developmental, anatomical, and functional characteristics which distinguish it from other joints of this type. We will discuss how this joint is similar as well as different than a lot of other joints that we have in our bodies, and how we can manage this. Because the TMJ is a synovial joint, it is put in a whole other category. We will discuss why the TMJ is important and how this is significant for how we use our jaw.
We will not be covering temporomandibular joint disorder in this presentation, but I believe it is important to know what this disorder is in order to distinguish it from the actual joint. Here is the definition of temporomandibular joint disorder from Wikipedia: Temporomandibular joint disorder, TMJD (in the medical literature TMD), or TMJ syndrome, is an umbrella term covering acute or chronic pain, especially in the muscles of mastication, and/or inflammation of the temporomandibular joint, which connects the mandible to the skull. The primary cause is muscular hyperactivity or parafunction (not using the joint for what it was made for), as in the case of bruxism with secondary effects on the oral musculoskeletal system, like various types of displacement of the disk in the temporomandibular joint. The disorder and resultant dysfunction can result in significant pain, which is the most common TMD symptom, combined with impairment of function. Because the disorder transcends the boundaries between several healthcare disciplines - in particular, dentistry and neurology - there are a variety of treatment approaches. When I read this definition, I see many interesting things. Lay people with access to internet will be checking out Wikipedia and ask themselves if they have this, what do I do with this, and where do I go for this. I am hoping that they will come to physical therapists because there is a lot in this definition that we can work with. Hopefully after today you will understand where the muscles are attached and how the disk works normally. Then you will see why and how we can affect this joint in a positive way.
