Chronic pain in the temporomandibular joint (TMJ) and/or masticatory muscles affects more than 10% of adults at any one time, and one-third of adults will experience symptoms of temporomandibular joint dysfunction (TMD) over their lifespan. Longitudinal data suggest that TMDs are a group of enduring or recurrent conditions that, for many patients, are resistant to treatment. TMD affects individuals across all socioeconomic and ethnic groups. In a study of TMD patients in Kaiser Permanente Northwest (KPNW) in 1990–1995, the mean age was 40.5 years, and 80% of the patients were female.
When this joint is injured or damaged, it can lead to a localized pain disorder called temporomandibular joint (TMJ) syndrome. Causes of temporomandibular joint (TMJ) syndrome include injury to the teeth or jaw, misalignment of the teeth or jaw, teeth grinding, poor posture, stress, arthritis, and gum chewing.
The temporomandibular acts like a sliding hinge, connecting your jawbone to your skull. There is one joint on each side of your jaw. TMJ disorders — a type of temporomandibular disorder or TMD — can cause pain in the jaw joint and in the muscles that control jaw movement. The exact cause of a person’s TMJ disorder is often difficult to determine. It could be due to a combination of factors, such as genetics, arthritis or jaw injury. Tests carried out in adults with ‘clicking joints’ have shown a saggitally shorter maxilla and mandibular diagnonal, whereas adults with ‘crepitating joints’ have, in addition, a shorter anterior and posterior cranial base and pharynx. It is concluded that the reported TMD signs in adults are associated with a sagittal shorter midface. (Am J Orthod Dentofac Orthop 1996;110:73-8.)
Pain relief is the primary therapeutic objective of TMD treatments. Common conventional treatments include anti-inflammatory, analgesic, antidepressant, and other medications used for chronic pain; intra-oral occlusal appliances; physiotherapy; occlusal equilibration and reconstruction; TMJ surgery; arthroscopy; and bio-behavioural treatments such as biofeedback, hypnosis, cognitive-behavioural therapy, and education. 
Traditional Chinese Medicine (TCM) have investigated the clinical effects of laser acupuncture therapy for temporomandibular disorders (TMD) after ineffective previous treatments. A retrospective observational study was conducted in 29 treatment-resistant TMD patients (25 women, 4 men; age range 17‒67 years). Subjects were treated 3 times per week for 4 weeks with the Handylaser Trion (GaAlAs laser diode, 810 nm, 150 mW, pulsed waves), which delivered 0.375 J of energy (5 s) to ST7, ST6, and LI4 and 3 J (40 s) to each Ashi point, 7.5‒26.25 J/cm2 in total. The visual analog scale (VAS) and maximal mouth opening (MMO) were evaluated before and after treatment. VAS analysis showed that the patients were free of pain at rest (endpoint) after 5.90±6.08 sessions of laser acupuncture for acute TMD and after 16.21±17.98 sessions for chronic TMD. The VAS score on palpation of the temporomandibular joint reduced to 0.30±0.67 for patients with acute TMD (p=0.005) and to 0.47±0.84 for those with chronic TMD (p<0.001). The MMO significantly increased in patients with acute TMD (7.80±5.43 mm, p=0.008) and in patients with chronic TMD (15.58±7.87 mm, p<0.001). Therefore, patients suffering from treatment-resistant TMD symptoms improved after laser acupuncture therapy. [Source: Wen-Long Hu; Kaohsiung Chang Gung Memorial Hospital]
Other studies point to Acupuncture, Alexander Technique and Chiropractic care (Gonstead technique) as ideal options for reducing symptoms.
TMJ syndrome may cause ear pain, ringing in the ears (tinnitus), and hearing loss.