Clicking in the TMJ is an annoying and even alarming symptom. There is disagreement concerning its etiology.
However, there are two general concepts:
• Disorders in the meniscus proper: Which include loose articular cartilage, bending and straightening of the meniscus and roughening of the meniscus due to pathological
• Muscles incoordination: Clicking is due to displacement of the meniscus due to over action or irregular action of the
external peterygoid muscle. As the disc is attached anteriorly to the lateral pterygoid muscle and has a loose attachment to the capsule posteriorly, incoordination of the lateral pterygoid muscle during mandibular opening or closing may result in the following:
- The disc may be held in place while the mandible is displaced posteriorly.
- The mandible is stabilized while the disc is displaced anteriorly
- In most cases a combination of the two possibilities occur.
- Clicking is more common in young persons.
- May disappear spontaneously without recurrence or reappear on the other side.
- During physical examination clicking may disappear.
- Some people can voluntary
induce clicking by deliberating incoordination of the muscles. Others can voluntary eliminate clicking by deliberating muscle coordination.
Clicking is a benign symptom and has no serious complication.
Accordingly it should not be treated aggressively except in the following cases:
- Patients in whom clicking is so audible to others.
- Patients in whom clicking is followed by painful limitation of mandibular opening.
- Patients in
whom anxiety is so great that they continue to be disturbed by the symptom.
Many procedures are of value in the treatment of clicking this include exercises, physiological rehabilitation, occlusal adjustment, high condylectomy
and condylectomy in sever cases.
MYOFACIAL PAIN DYSFUNCTION SYNDROME (MPD)
This condition is a functional disorder
of the temporomandibular joint that is characterized by discomfort in the oral and para-oral region with mandibular movement. Usually it comprises a combination of muscular pain and mandibular dysfunction.
was thought that the condition occur more in females between 30-50 years of age, however recently it was reported that there is no sex predilection, but females usually seek treatment more than males.
Signs And Symptoms:
Pain: The pain is dull and unilateral, which may be intense in the morning or may be minimal and increase during day. The site of pain may range from the back of the head and neck posteriorly to the temporal era superiorly and the angle of the mandible
• Tenderness of the masticatory and related muscles: Palpation of the masticatory muscles and related muscles will reveal the presence of painful areas which represent a spasmodic part of the muscle
which is capable of referring pain to remote areas. For example pain in the temporalis muscle may be referred to the maxillary dentation and pain in the masseter may be referred to posterior teeth and ear region.
However, clicking alone is not diagnostic for MPD, but if accompanied by pain and muscle tenderness it is diagnostic.
• Limitation of mandibular movement: Usually there is some limitation in mandibular movement,
opening, closing and lateral movement.
• Lack of evidence of organic changes in the TMJ and no tenderness on palpation of the joint. This two finding are diagnostic.
The condition is multifactorial, however, the spasm of the masticatory muscles is the primary cause for the pain and mandibular dysfunction. There are two theories regarding the cause of the myospasm which are:
Occlusal disharmony: The myospasm is due to the disharmony between the position of the condyle and the dental occlusion. Normally in centric occlusion position the condyle is centrally placed in the fossa, abnormal condylar position may be caused
by malocclusion, burxism, premature contact and loss of posterior teeth. This theory is supported by the common presence of para-habits as clenching in patients suffering from MPD and the improvement which occur after occlusal adjustment.
Psychological stress: Patient response to stress is the main factor and occlusal disharmony acts as a trigger in patients spychologically predisposed. Response to stress may be in the form of increased muscle tension including masticatory muscles.
Usually there is barafunctional habits as clenching and grinding of teeth. In favor to this concept is the following:
- Hyperactivity of the jaw muscles is initiated centrally by the environmental stresses.
- MPD,s patients shows generalized
skeletal muscle hyperactivity.
- Many MPDs patients either having or had had other spychological predisposed diseases as peptic ulcer and migraine.
- High percentage of positive results obtained with the use of placebo drugs and placebo splints.
The syndrome is basically a myoskeletal disorder. Dysfunction is sue to excessive muscular activity which leads to injury to the TMJ, dental apparatus and the muscles themselves. This in turn result
in degenerative changes in the TMJ. The objectives of treatment of MPD are:
- Control pain and discomfort.
- Elimination of occlusal disharmony.
- Lowering the psychological stress or tension.
of jaw movement: This line of treatment provides rest of the masticatory muscles for 2-3 weeks. Immobilization may be performed by the use of wires and splints, but best to performed voluntarily by the patient following
liquid and soft diet regimen.
Occlusal adjustment: This is done to maintain and improve the muscle equilibrium and coordination and in turn the joint function.
Splints and occlusal bit planes: It has the advantage of eliminating the occlusal interference and provides a stable position of the teeth during movement. Also it minimize the effect of the teeth in bruxism.
Thermotherapy: Heat application leads to vasodilatation and washing of the noxious metabolic
products which accumulate in the muscles due to the sustained state of contraction. Also heat application has muscle relaxant effect and counterirritant effect which aid in elimination of the painful stimuli.
Muscular exercises: Also has muscle relaxant effect and reestablish muscular coordination.
Muscle relaxants therapy: The aim is to relief
muscular spasm to interrupt the pain-spasm-pain cycle
Spychological therapy: The aim to decrease muscular spasm and increase the patient adaptive response to treatment .
Intramuscular injection of local anaesthesia: This technique is used to confirm the diagnosis and to provide a pain free period for the muscle exercises.
Dislocation is the displacement of the condyle out of the glenoid fossa where it is held anteriorly and superior to
the summit of the articular eminence, but within the capsule of the joint. On the other hand
The condyle most commonly become displaced anteriorly to be held anterior and superior to the eminence. In rare occasion, usually due to sever
trauma, the condyle may be displaced posteriorly cracking the tympanic plate or superiorly to be impacted in the middle cranial fossa.
- Extreme trauma.
- Sudden wide mandibular opening as in yawing.
- Prolonged wide opening.
- Capsular laxity as with chronic subluxation.
Signs And Symptoms:
- The mouth is opened and rigidly set in position with the chin protruded.
- Chin is tilted to the nonaffected
side in unilateral cases.
- In ability to close the mouth.
- There is usually sever pain.
- By palpation a depression is found anterior to the ear, anterior to which there is an elevation indicating the displaced condyle.
Acute dislocation: It usually occurs after sudden stretching of the masticatory muscles as in yawing or wide opening.
Recurrent dislocation: This term
is used when the dislocation of the condyle occurs several times with inability of the patient to reduce it by himself.
Subluxation: This is a term used for lack of a better term to identify a condition described
by the patient as the patient as the jaw momentarily lock, slip or going out of place with the bite off. Some authors describe subluxation as self-reducable dislocation.
Mechanism Of Dislocation:
Usually the condyle
and the disc passes the anterior slope of the articular tubercle when the mouth is fully opened. Dislocation occurred while the condyle is in this position is due to faulty muscular coordination. When, at the beginning of the closing movement, the lateral
pterygoid muscle remain contracted instead of relaxing, the elevator muscles will exert their force while the condyle is still on or anterior to the height of the articular tubercle. Dislocation is thus unavoidable.
Manual Reduction: Manual reduction is used in cases of acute or recurrent dislocation to set the displaced condyle back into the glenoid fossa. The operator stands infront of the patient with the thumbs on the molar region. The mandible is pressed
downward and backwards. Reduction is facilitated by applying topical anaesthesetic spray to the region of elevator muscles during reduction. After reduction four-tailed bandage is applied and the patient is instructed to restrict the mandibular opening for
Another technique for reduction of the displaced condyles is by standing behind the patient, stabilizing the patient’s head by your abdomen. The mandible is rotated in the same direction by pressing on the mandibule proper
rather than the occlusal plane.
II. To Prevent Recurrent Dislocation:
Immobilization: The aim is to keep the joint at rest for a considerable period of time to avoid extreme movements. This will
give time to loose ligament to recover. This method, however, interfere with function and has an unpleasant spychological effect on the patient.
Surgical methods: This include:
- Eminoplasty: Reduction
of the height of the articular eminence will facilitate self reduction of the condyle.
- Capsular tightening: Surgical tightening of the lux ligament of the capsule will prevent the anterior displacement of the condyle.
- Condylectomy: Removal
of the entire condyle is used as a final resort in sever unresponsive cases.