Shortcuts: What is TMJ? | Who can have TMJ Syndrome?
What are the common Symptoms of TMJ Syndrome?
What is MPD? | What is CMD?
The symptoms of TMD, MPD, and/or CMD
What should I do if I suspect TMD, MPD, or CMD?
The importance of a good bite and normal skeletal relationship

What is TMJ?

TMJ is an acronym for the temporomandibular joint or jaw joint in front of the ear. To be technical, it is the articulation between the temporal bone of the skull and mandible or lower jaw. The condyloid process of the mandible below is separated by a cartilaginous articular disk from the glenoid fossa of the temporal bone of the skull above. This articulation allows for the opening, closing, protrusion, retraction, and lateral movement of the mandible or lower jaw.

Problems associated with the TMJ or jaw joint are referred to as temporomandibular dysfunction or TMD. But common usage outside of the dental profession just refers to these problems as "TMJ".

Who can have TMJ Syndrome?

Millions of Americans suffer from undiagnosed TMD. TMD can afflict people of all ages, although the incidence is highest (37 to 63% depending on the epidemiologic study) in women between the ages of 20 and 44. The incidence has been reported to be 7:1 to 17:1 times higher in females than in males.

What are the common Symptoms of TMJ Syndrome?

Often, the first sign of TMD is a joint vibration or clicking or popping sound originating in the jaw joint, especially when opening widely. As the dysfunction progresses there frequently is pain or soreness in and around the jaw joints. The clicking becomes less frequent and eventually stops, but the ability to open fully decreases. The effort to open widely is met with increased strain and discomfort. In the advanced stages, the articular disk is permanently displaced and damaged beyond repair. The posterior ligament that limits the normal movement of the articular disk is perforated and stretched beyond repair. The TM joints show evidence of traumatic osteoarthritis characterized by excessive wear of the condylar process of the mandible against the opposing temporal bone.

What is MPD?

MPD is an acronym for myofascial pain disorder. This is a disorder of the masticatory or chewing muscles and their fascia, the fibrous membrane covering, supporting, and separating muscles. Fascia also unites the skin with underlying tissue. Fascia may be superficial, a nearly subcutaneous covering permitting free movement of the skin, or it may be deep, enveloping and binding muscles. MPD is essentially a myofascitis or inflammation of the muscle and its fascia. As a bit of trivia, this acronym also has many other meanings including multiple personality disorder, myoproliferative disorder, maximum permissible dosage, and muscle phosphorylase deficiency.

What is CMD?

CMD is an acronym for craniomandibular disorder. This syndrome describes a complex chronic and progressive disorder involving the head (cranium), neck (cervical vertebrae), lower jaw (mandible), and the supporting muscles of these structures. CMD recognizes the articulation of the cranium to the cervical vertebrae or neck as well as to the lower jaw. CMD broadens the scope of the treating physician’s concern. The F-S Index, so coined by Dr. Lawrence A. Funt and duly recognizing the contributions of Dr. Brendan Stack, shows the evolutionary, progressive and cumulative clinical progression of signs and symptoms of disorder in Craniomandibular pain patients.

The symptoms of TMD, MPD, and/or CMD often include:

• Pain or soreness in and around the jaw joints
• Headaches and migraines
• Facial pain
• Sounds in the jaw joints including clicking, popping, crunching, or grating
• Limited movement or locking of the jaw
• Pain behind the eyes
• Neck, shoulder, or back pain
• Earaches, stuffiness, or ringing
• Tooth grinding or clenching
• Tooth pain
• Numbness in fingers and arms
• Dizziness
• Difficulty swallowing
• Sleep apnea or difficulty sleeping

Left untreated, the TMD symptoms increase in number and severity with age. Finally, there is irreparable damage and a permanent disability.

What should I do if I suspect TMD, MPD, or CMD?

Schedule an appointment with Dr. McAnnally. Following a clinical examination and evaluation of diagnostic records, Dr. McAnnally will present his diagnostic observations and discuss treatment options with you. Click here to make an appointment now.

The importance of a good bite and normal skeletal relationship.

The bite or how the teeth come together is important. If the teeth are not in their correct positions, the teeth can force the jaw out of its correct position. This, in turn, will cause problems in the jaw joints and muscles and fascia of the masticatory musculature. We invariably adapt to close into the best fit of our teeth whether the bite is good or bad. The nerves to the teeth insure that the teeth will find their best fit to avoid traumatic contact and possible enamel fracture upon closure. The anatomical fit of the jaw joints is secondary. If there is a discrepancy between good fit of the teeth and good fit of the condylar process of the mandible in the temporal fossa, the teeth will prevail and the joints will suffer.

This explains the rationale for first phase diagnostic splint therapy. Bite splints disengage the teeth and allow the lower jaw to assume a position and path of closure consistent with good jaw joint function and jaw joint and masticatory muscle comfort. It should also be clear why splints are diagnostic aids and rarely corrective devices. When the splint is discontinued, the dental interferences that deflect the jaw from a normal, pain-free trajectory of closure once again exert their deleterious affect. Bite splints are occasionally helpful unloading the joint while recent joint injuries or transient sprains heal. The chronic, progressive pathology caused by the constant microtrauma associated with long-standing malocclusions will not respond favorably to splints and generally require occlusal adjustment, orthodontics, prosthetic, or dentofacial orthopedic solutions.

Finally, 80% of headaches are muscle tension headaches originating in the masticatory musculature. If you have over two headaches a month you probably should be screened for clinical signs or symptoms of MPD, TMD, or CMD.

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