The temporomandibular joint â€“ the TMJ isthe joint between the lower jawbone the mandible and the temporal bone of the skull.The TMJ is responsible for jaw movement and enables chewing, talking and yawning. Temporomandibulardisorders, or TMD, refer to a group of conditions characterized by pain in the jaw area andlimited movement of the mandible. TMD may be caused by problems in the joint itselfor in the muscles surrounding the joint. Problems in the joint include: arthritis, inflammationand internal derangements. When the problem is in the muscles, the condition is calledmyofascial pain syndrome. Myofascial pain syndrome is very common andcan occur in patients with a normal temporomandibular
joint. The syndrome is characterized by presenceof hyperirritable spots located in skeletal muscles called trigger points. A trigger pointcan be felt as a nodule of muscle with harder than normal consistency. Palpation of triggerpoints may elicit pain in a different location. This is called referred pain.Trigger points are developed as a result of muscle overuse. Commonly, the muscles of chewing,or mastication, are overworked when patients excessively clench or grind their teeth unconsciouslyduring sleep. The medical term for this condition is â€œnocturnal bruxismâ€�. A trigger pointis composed of many contraction knots where individual muscle fibers contract and cannotrelax. The sustained contraction of muscle
sarcomeres compresses local blood supply,resulting in energy shortage of the area. This metabolic crisis activates pain receptors,generating a regional pain pattern that follows a specific nerve passage. The pain patternsare therefore consistent and are well documented for various muscles.Trigger points in the masseter refer pain to the cheeks, lower jaw, upper and lowermolar teeth, eyebrow, inside the ear and around the TMJ area. Trigger points in the temporalisare also associated with headache and toothache from upper teeth. The main culprits of myofascialpain in the TMJ area are the pterygoid muscles. Trigger points in medial pterygoid refer painto the TMJ region in front of the ear, inside
the mouth and upper outside of the neck. Theymay also manifest as sore throat and difficulty swallowing. Pain from lateral pterygoid triggerpoints can be felt in front of the ear and on the upper jaw.Treatments aim to address bruxism, to relieve muscle spasm and release trigger points. Treatmentoptions include: Therapies: stress management, behavior therapy,biofeedback to encourage relaxation. Dental night guards: Splints and mouth guards to protect the teeth from damage. Medication: pain relievers, muscle relaxants,botox injections. Trigger points release techniques such asneedling and â€œspray and stretchâ€�.