Diagnosis and treatment of myofacial pain-dysfunction (MPD) syndrome

CRANIOMANDIBULAR SECTION

GEORGE

FUNCTION

A:ND DYSFUNCTTON

EDITOR

A. ZARB

Diagnosis and treatment of myofacial pain-dysfunction (MPD) syndrome Daniel

M. Laskin,

Medical College Chicago, 111.

D.D.S., M.S.,” and Sanford

of Virginia,

School of Dentistry,

Block, D.D.S., LL.B.**

Richmond,

M

(MPD) syndrome is a yofacial pain-dysfunction psychophysiologic disease that primarily involves the muscles of mastication.‘*’ The condition is characterized by dull, aching, radiating pain that may become acute during use of the jaw, and mandibular dysfunction that generally involves a limitation of opening. Generally the condition involves only one side of the face and, upon examination, tenderness can usually be elicited in one or more of the muscles of mastication or their tendinous attachments. Although headache is frequently mentioned as a symptom, the only type of headache that may be directly or indirectly part of the syndrome is muscle spasm or tension headache, with other types being coincidental findings. The same is true for such complaints as diminished hearing, tinnitus, burning tongue, and neuralgic pains. Although MPD syndrome starts as a functional disorder, it can ultimately lead to organic changes in the temporomandibular joint (TMJ) and the masticatory muscles, and even cause possible alterations in the dentition. MPD syndrome is believed to be a stress-related disorder.‘*‘, * It is hypothesized that centrally induced increases in muscle tension, frequently combined with the presence of parafunctional habits such as clenching or grinding of the teeth, result in muscle fatigue and spasm that produce the pain and dysfunction. Similar symptoms, however, occasionally can also result from muscular overextension, muscle overcontraction, or trauma (Fig. 1). Women are affected by MPD syndrome more frequently than men, with the ratio in various reports ranging from 3:l to 5:l. 5,6 Although the condition can occur in children, the greatest incidence appears to be in the 20 to 40 years age group.

MAKING

THE DIAGNOSIS

Because the cardinal signs and symptoms of MPD syndrome are similar to those produced by many organic

*Professor Surgery Medical **Assistant Illinois, Surgery.

and Chairman, Department of Oral and Maxillofacial and Director of the TMJ and Facial Pain Research Center, College of Virginia, School of Dentistry. Professor of Oral and Maxillofacial Surgery, University of College of Dentistry; Director of Dentistry and Oral Swedish Convenant Hospital, Chicago, Ill.

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Va., and University

of Illinois,

College of I)cntihtr,

_

problems involving the TMJ, as well as by a variety of nonarticular conditions, the diagnosis of this syndrome can be difficult, requiring a careful history and a thorough clinical evaluation. Radiographs may also be helpful. These may include periapical views of the teeth and screening views (transcranial, transpharyngeal, or panoramic) of the TMJs. If the screening views of the TMJs show some abnormality, tomographic views arc usually advisable. Arthrography can also be useful in determining the position of the meniscus when an internal derangement of the TMJ is being considered. Depending upon the suspected condition, other radiographic views of the head and neck, C‘:T scans,’ and scintigraphy’ may be needed to establish a final diagnosis. In addition, certain laboratory tests may be helpful in some instances These include the complete blood cell count if an infection is suspected; serum calcium, phosphorous, and alkaline phosphatase measurements for possible bone disease; serum uric acid determination for gout; serum creatinine and creatine phosphokinase levels as indicators of muscle disease; and erythrocyte sedimentation rate, rheumatoid factor, and latex fixation tests for suspected rheumatoid arthritis. Elec?romyography can be used to evaluate muscle function. Psychologic evaluation and psychometric testing are good research tools, but have little diagnostic value other than determining the presence of any associated abnormal behavioral characteristics. Two major groups of conditions must be considered in the differential diagnosis of MPD syndrome: the nonartitular problems that can mimic MPD syndrome, and the various pathologic disorders of the TMJ that may sometimes also produce similar signs and symptoms. Nonarticular problems include conditions that produce pain resembling that of MPD syndrome (Table I) and those that produce mainly limitation nf jaw opening (Table II). The pathologic conditions involving the TMJ are the same as those that involve other joints of the body (Table III). However, because in young patients the articular surface of the mandibular condyle also serves as a growth site, any pathologic condition involving the joint that alters the condylar surface will also have an effect upon mandibular and, subsequently, facial growth. Thus, pathologic conditions occurring in this region 75

LASKIN

STRESS

__t

MUSCULAR HY PERACTIVITY

MUSCULAk

-

“Dental

AND

BLOCK

Irritation’

FATIGUE

Fig. 1. Etiology of myofacial pain-dysfunction (MPD) syndrome. (Modified from Laskin DM: Etiology of the pain-dysfunction syndrome. J Am Dent Assoc 79:147, 1969.)

manifest themselves differently than in other joints of the body. Because a large number of conditions can produce signs and symptoms similar to those of MPD syndrome, establishing an accurate diagnosis can be extremely difficult at times. However, careful attention to the details of history taking and physical examination, and the use of this information as a guide to eliminating unrelated conditions, can facilitate the process.

TREATMENT

OF MPD SYNDROME

Management of MPD syndrome is founded on certain basic principles that include the establishment of an accurate diagnosis, gradual escalation of therapy, and avoidance of irreversible forms of treatment. It is also based on the clinician’s understanding that MPD syndrome is a psychophysiologic disease and that the results of treatment must be considered in the light of placebo effects9-‘2and the contributions of a good doctor-patient relationship. 13,14This means that treatment should be geared toward management rather than a definitive cure inasmuch as the causes of a psychophysiologic disorder may be more difficult to eliminate than those of a disease of microbiologic origin. Finally, the ability of patients to understand and accept the psychophysiologic basis for the disease is essential in their ultimately dealing with the problem. Several different treatments have been recommended for MPD syndrome, ranging from structural alterations to psychotherapy. The following is a discussion of various therapeutic modalities that have been used successfully by many clinicians in the management of patients with MPD syndrome and have fulfilled the requirement of not producing irreversible structural 76

changes. This discussion will be followed by a treatment plan explaining the proper use of these modalities.

Initial

explanation

of the problem

The first step in the management of patients with MPD syndrome is to provide them with some understanding of their problem. Because patients often have difficulty accepting a psychophysiologic explanation for their disease, the initial discussion should deal with the issue of muscle fatigue and spasm as the cause of the pain and dysfunction, delaying consideration of stress and psychologic factors until the condition has improved and the patient’s confidence has been gained. Relating the symptoms to specific masticatory muscles helps the patient to understand the reason for the type and location of the pain; for example, headache from the temporal muscle, jaw ache from the masseter muscle, discomfort when swallowing from the medial pterygoid muscle, and earache from the lateral pterygoid muscle. Assuring the patient that he or she does not have cancer or arthritis can help relieve anxiety about the persistence of the symptoms.

Therapeutic modalities There are a number of simple yet effective things that the patient can do at home to reduce muscle fatigue, spasm, and pain, increase mandibular mobility, and restore good masticatory function. These include proper diet, the limitation of jaw movement, avoidance of parafunctional habits, and use of heat and massage. There are other specific treatment modalities that require professional administration or prescription. Therapy at home. The diet should be of a soft, nonchewy character. Food should be cut into small

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Table

.-____

AND

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I. Differential

OF MPD

diagnosis

SYNDROME

of nonarticular Limitation

Disorder

conditions

mimicking _____Muscle tenderness

Pulpitis

No

No

Pericoronitis

Yes

Possible

Otitis media

No

No

Parotitis

Yes

No

Sinusitis

No

No

No

No

No

No

No

No

Yes

No

No

No

Trigeminal

Atypical

Temporal

neuralgia

(vascular)

neuralgia

arteritis

Trotter’s syndrome (nasopharyngeal

carcinoma)

Eagle’s syndrome (elongated styioid process)

pieces so that excessive chewing is not necessary. Jaw motion should be limited and wide opening, such as when yawning, should be avoided. Yawning should be consciously controlled or restricted by placing the hand under the chin or by bending the head down so the chin touches the chest. Parafunctional habits, such as clenching or grinding the teeth, should be avoided. Although patients are usually aware of a grinding habit, many clench their teeth unconsciously. They should be instructed to check for clenching and to remember to keep their teeth apart if they recognize such activity. Anterior splints that prevent occlusion of the posterior teeth can also be used to eliminate clenching and grinding, particularly during sleep.‘O Other parafunctional habits such as fingernail biting, lip biting, cheek biting, and holding pipes or cigars in the mouth for prolonged periods must also be avoided since these habits also can induce masticatory muscle fatigue. Heat and massage are beneficial to patients with MPD syndrome. Moist heat applications should be used

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pain of MPD syndrome ---_ ~. Diagnostic features

..~ ~-.-..---

Mild to severe ache or throbbing, intcrmlttent or constant; aggravated by thermal changes; eliminated by dental anesthesia; positive x-ray findings Persistent mild to severe ache: diltigxliv swallowing; possible fever; local inflammation; relieved with dent,4 anesthesia Moderate to severe earache, pain cimstant, fever; usually history of upper rt*+ratory infection; no relief with dental arrcsthesia Constant aching pain, worse when eating; pressure feeling; absent sallvar!, Itow. ear lobe elevated; ductal suppuration Constant aching or throbbing, w~~r;e when change head position; nasal dissthesx Diffuse throbbing or burning pain <>,tlong duration; often associated autonc,m~c symptoms; no relief with drntJ1 .lnrsthesia Constant throbbing preauricu!ar JXIL~; arterl prominent and tender; low grdd? fever: may have visual problems, clcv,ltcsd ~~~drmentation ra tr Aching pain in ear, side of fact, I~~wer law; deafness; nasal obstruction ~:t~r.~l~-a! lymphadenopathy Mild to sharp stabbing pain in e,~r, throat, retromandible; provoked by swaiiowing, turn,ng head, carotid comprc:ss;on, usually posttonsillectomy, stylold pr<~t’s-, longer than 2.5 cm

for a half hour at least twice daily. These applications should be placed over the involved masticatory muscles for 10 minutes, followed by a S-minute pause, and then reapplied two more times in the same manner. Between heat applications, mild exercise using hinge motion within the limit of pain may be used to maintain muscle function. Massage using a moderate kneading motion over the involvled area will also aid the return of venous blood, lymph, and catabolites into the main circulation and help reduce muscle pain and spasm. Short-term medication. Because muscle spasm and pain are part of the MPD syndrome, muscle relaxants and analgesic drugs can help to resolve the problem.“, ” Spasm produces pain that in turn produces more spasm; muscle relaxant drugs can interrupt this vicious cycle. However, they are more effective if used in conjunction with a pain-relieving medication. Generally, only a mild analgesic is needed. If patients state that they require a narcotic, drug dependency or a wrong diagnosis should be considered. Examples of analgesics that may be used effectively are: aspirin, 10 gr buffered or coated, three

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Table II. Differential

diagnosis

of nonarticular

conditions

producing

limitation

AND

BLOCK

of mandibular

movement Disorder

Pain

Muscle tenderness

Odontogenic infection

Yes

Yes

Nonodontogenic infection

Yes

Yes

Myositis

Yes

Yes

No

No

Possible

Possible

Scleroderma

No

No

Hysteria

No

No

Tetanus

Yes

No

Rxtrapyramidal reaction

No

No

Possible

No

No

No

Myositis

ossificans

Neoplasia

Depressed zygomatic arch Osteochondroma coronoid process

times a day; acetaminophen, 650 mg, three times a day; or propoxyphene (Darvocet-N 100) 1 to 2 tabs, three times a day. The benzodiazepines are the drugs most often prescribed as muscle relaxants. These agents also have tranquilizing properties that can be beneficial in reliev; ing tension. The best known and most widely used benzodiazepine is diazepam (Valium), which is prescribed in the range of 2 mg three times a day to 5 mg four times a day. l5 A gain, it should be taken in conjunction with an analgesic for the best effect. As an alternative to diazepam, meprobamate may be used in a dosage of 400 mg three times a day.’ The use of drugs with only muscle relaxant properties and no sedative or tranquilizing effects, such as carisoprodol (Soma) or methocarbama1 (Robaxin), have generally not been successful for the treatment of MPD syndrome. Patients with long-standing MPD syndrome and proven depression may benefit from the use of an antidepressant drug. l6 These drugs have many autonomic side effects that may discourage the patient from

78

Diagnostic

features

Fever; swelling; positive x-ray findings; tooth tender to percussion; pain relieved and movement improved with dental anesthesia Fever; swelling; negative dental findings on x-ray; dental anesthesia may not relieve pain or improve jaw movement Sudden onset; movement associated with pain; areas of muscle tenderness; usually no fever Palpable nodules seen as radio-opaque areas on x-ray; involvement of nonmasticatory muscles Palpable mass; regional nodes may be enlarged; may have paresthesia; x-ray may show bone involvement Skin hard and atrophic; mask-like faces; paresthesias; arthritic joint pain; widening of periodontal ligament Sudden onset after psychological trauma; no physical findings; jaw opens easily under general anesthesia Recent wound; stiffness of neck; difficulty swallowing; spasm of facial muscles; headache Patient on antipsychotic drug or phenothiazine tranquilizer; hypertonic movement; lip smacking; spontaneous chewing motions History of trauma; facial depression; positive x-ray findings Gradual limitation; jaw may deviate to unaffected side; possible clicking sound on jaw movement; positive x-ray findings

taking them. The most commonly used antidepressant drugs are the tricyclic antidepressants, of which amitriptyline (Elavil) is the best example. It is generally prescribed in an initial dose of 25 mg at bedtime and gradually increased to 75 mg at bedtime. The beneficial effects are derived from mood elevation and the drug’s analgesic properties. It should be used for at least 2 months because it may take as long as a month to reach its maximum therapeutic effect. If it is necessary to continue beyond this time, it is often better to place the patient under a physician’s care for the depression. Because there are a variety of side effects that may accompany the use of the antianxiety and antidepressant drugs, as well as various medical contraindications to their use, they should not be prescribed without familiarity with these potential hazards. Splint therapy. When the previously described forms of home therapy have not been completely successful, or there is a history or suspicion of a tooth clenching or grinding habit, splint therapy should be considered. Numerous types have been used but the Hawley-type

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Table III. Differential Disorder Agenesis

OF MPD

SYNDROME

diagnosis

of temporomandibular Pain

Limitation

No

Yes

Condylar

hypoplasia

No

No

Condylar

hyperplasia

No

No

Possible

Yes

Yes

No

Yes

Yes

Yes

Yes

Degenerative arthritis

Yes

Yes

Ankylosis

No

Yes

Internal disk derangement

Yes

Yes

Neoplasia

Infectious

arthritis

Rheumatoid

Traumatic

arthritis

arthritis

upper anterior splint is probably the most effective because it prevents occlusion of the posterior teeth and thereby prevents most forms of parafunctional activity. The anterior platform should be flat and nonguiding and should produce minimal separation of the occlusal surfaces (approximately 2 mm). The splint should not be worn continuously since supereruption of the posterior teeth can occur. Generally, it is worn at night and for 5 to 6 hours during the day. The specific periods of use

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joint disease Diagnostic features Congenital; usually unilateral; mandible deviates to affected side; unaffected side long and flat; severe malocclusion; often ear abnormalities; x-ray shows iondylar deficiency Congenital or acquired; affected side has short mandibular body and ra,mus. fullness of face, deviation of chin; body of mandible elongated and face fl,lt on unaffected side; malocclusion; x-ray shows condylar deformity, antegonial notching Facial asymmetry with deviation of chin to unaffected side; cross-bite malocclusion; prognathic appearance; lower border of mandible often convex on affected side; x-ray shows symmetrical enlargement of condyle Mandible may deviate to affected side; x-rays show enlarged, irregularly shaped condyle or bone destruction depending on type of tumor; unilateral condition Signs of infection; may be part of systemic disease; x-ray may be negative early, later can show bone destruction; fluctuance may be present; pus may be obtained on aspiration; usually unilateral Signs of inflammation; findings in other joints (hands, wrists, feet, elbows, ankles); pos.1tive laboratory tests; retarded mandibular growth in children; anterior open bite in adults; x-rav shows bone destruction; usually bilateral History of trauma; x-ray negative except for possible widening of joint space; local tenderness; usually unilateral Unilateral joint tenderness; often crepitus; TM1 may be only joint involved, x-ray may be negative or show condylar flattening, lipping, spurring, or erosion Usually unilateral but can be bilateral; may be history of trauma; young patient may show retarded mandibular growth; x-rays show loss of normal joint architecture Pain exacerbated by function; clicking on opening, or opening limited to under 25 mm with no click; positive arthrographic findings; may be history of trauma: usually uni :ateral

during the daytime hours depends on the history of the symptoms. Usually it is worn in the afternoon and early evening. The patient should be instructed not to dench against the splint and to rest the teeth lightly against the platform only when necessary. When a Class 11 malocclusion exists, it will be necessary to u.se a maxillary splint with full occlusal coverage. This type of splint can also be used in patients who grind but do not clench their teeth or in those who

79

LASKIN

must wear a splint 24 hours a day, because the occlusion will remain stable. The platform must be flat so as not to lock or guide the mandible into either an anterior or retruded position. This is not a functional splint and should not be worn during eating. All splints must be adjusted periodically during treatment to eliminate premature tooth contacts that may occur as the masticatory muscles relax and return the jaw and teeth to a more normal relationship. Physical therapy. The various forms of physical therapy recommended for use in patients with MPD syndrome are directed at reducing muscle tension and spasm and improving jaw function, and include ultrasound, electrogalvanic stimulation, and cryotherapy.” Ultrasound produces vibrations within the tissue that cause particle collision and the release of energy. This energy reaction results in the production of heat.” The physiologic effect of this deep heat and vibration is a reduction in muscle tension and an increase in tissue elasticity. There are also mild analgesic and antiinflammatory actions as a result of improved circulation. In MPD syndrome the treatment is used over the masseter and the temporalis muscles. The sound head is moved slowly to avoid excessive heat build up. A maximal tolerable level is recommended and this is adjusted according to the area of application. A tolerance will develop during the treatment and greater intensities may then be applied. The applications last 10 to 15 minutes and can be given twice daily. Muscle tenderness usually resolves in 1 to 2 weeks. Care must be taken not to apply this therapy when there is acute inflammation, and it must not be used in patients with vascular insufficiency, over malignant areas, over metallic implants, or in patients with cardiac pacemakers. High voltage electrogalvanic stimulation involves the use of a monophasic, pulsed direct current applied through an electrode placed on the skin over the involved muscle. The muscle can be activated at frequencies ranging from 4 to 80 pulses per second. Treatment is usually applied for 10 to 15 minutes 2 to 3 times a week. The electrical stimulation of the muscle increases circulation, reduces pain and spasm, and increases resistance to fatigue. It has been shown to be effective in improving the range of motion and diminishing pain in patients with MPD syndrome.19 The use of cold (cryotherapy) reduces tissue temperature, causes local analgesia, has anti-inflammatory effects, and can diminish muscle spasm. The analgesic effects are due to a decrease in end organ activity and pain fiber conduction. In addition, the cold-mediating nerve fiber input creates increased activity at,the spinal gate and reduces the influence of the pain fibers. The cooling effect also creates vasoconstriction and reduces myoneural transmission and neuromuscular activity. 80

AND

BLOCK

The use of cold, or cryotherapy, in the treatment of MPD syndrome is useful in the acute phases of the disorder. A vapor-coolant svay (ethyl chloride or fluorimethane) is applied over the involved masticatory muscles. Because of the volatile nature of the sprays, care must be taken to protect the eyes and ears. The bottle is held 1 to 1% feet away from the target muscle and the spray is applied in a circular motion for 10 seconds. The spray is stopped when slight frosting appears on the skin. Immediately after the application, a red area will be present. The procedure is repeated two more times, with a lo-second interval in between. The mandible is then mobilized by gently stretching to the maximal tolerated opening. Care should be taken not to produce excessive pain during this exercise. The mandibular range of motion should improve and the patient should experience less pain and stiffness after the treatment. The application should be repeated twice daily for 2 to 3 days. If no improvement is noted in this period, cryotherapy should be discontinued. Ice packs can also be beneficial in the acute phase of MPD syndrome. The cold applications are used for 10 to 15 minutes, removed, and reapplied after 5 to 10 minutes. This can be repeated 3 to 4 times daily. Moderate stretching exercise is instituted after the treatment. As with the vapor-coolant sprays, the use of ice packs also helps reduce pain and stiffness. Relaxation therapy. Because MPD syndrome is basically a problem related to increased muscle tension and spasm, any technique designed to induce muscle relaxation should be helpful. Among the modalities that have proven to be effective are biofeedback,‘2,20 conditioned relaxation,2’x 22and hypnosis.23s24 Electromyographic biofeedback involves supplying the patient with visual or auditory information about the moment-to-moment contractile status of the muscle being monitored. The patient then concentrates on relaxing the muscle and, if effective, this is reflected by a corresponding reduction in the level of the graphic representation or the audible sound. The patient thus learns to produce muscle relaxation. Although the procedure concentrates on only one muscle at a time, learning to reduce its activity has a generalized relaxing effect. The auditory electromyographic biofeedback unit is used by placing an electrode over the affected masticatory muscle. The patient sits comfortably in a semireclining position. Earphones are placed on the patient and the machine is adjusted to a beginning level. When the patient clenches or tenses the masticatory muscles, the EMG activity increases causing a louder audible response. The patient is then instructed to relax, creating a reduction in EMG activity that is reflected by a lowering of the sound. The sensitivity of the machine is increased gradually and the patient has to achieve a greater state of relaxation to maintain or reduce the JULY 1986

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audible feedback. The biofeedback is used for two 30-minute sessions each week for 6 weeks. The patient is instructed to practice the relaxed state at home each night for the same length of time. This therapy requires continued practice to maintain the reduced muscle activity. Patient response to biofeedback is generally good as a feeling of self-control and positive motivation becomes apparent. Conditioned relaxation is similar to biofeedback in its end result but differs in that the patient does not have the benefit of a feedback indicator. This is actually an advantage because the person does not become dependent upon a machine to indicate relaxation, but instead develops a definite awareness of how the state of relaxation actually feels. The patients are taught to contract and relax the various muscles of the body, including the muscles of mastication, learning to appreciate the contrast between the two states. Conditioned relaxation can be taught by the clinician, or the patient can learn it by using instructional audiocassette tapes. In the latter instance, the patient should still have personal instruction initially to assure that the instructions are understood. The use of an altered state of consciousness to induce relaxation, such as produced by hypnosis, transcendental meditation (TM), and yoga, can also be useful in the treatment of MPD syndrome. Although TM and yoga can be self-taught, altered consciousness definitely requires instruction from a trained hypnotherapist. Hypnosis may not only aid in the reduction of tension, but can also be used to eliminate parafunctional habits such as fingernail biting, lip or cheek biting, and bruxism Anesthetic injections. The injection of local anesthetics into the tender and painful areas in the masticatory and cervical muscles has been used for diagnostic (establishing the source of the pain) and therapeutic (relieving myospasm) purposes in patients with MPD syndrome.*’ Essential in the use of this technique is a thorough knowledge of the anatomy of the region to be injected. The local anesthetic should not contain epinephrine or other vasoconstrictors. The injection is done under aseptic conditions and with the use of proper aspiration technique. Generally, no more than 0.5 cc is injected in each region. Care must be taken to avoid the main branches of the facial nerve, and the patient should be warned that a temporary (2 to 3 hour) paresis or paralysis of some of the facial muscles may occur despite all precautions. If the diagnosis is correct, the local anesthetic injection will relieve the pain and reduce the muscle spasm. During this time, the mandible can be gently exercised to stretch the muscles and improve mobility. Massage is also helpful in producing muscle relaxation. The procedure can be repeated several times within a week, if THE JOURNAL

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effective; thereafter other, less invasive forms of treatment such as ultrasound or cryotherapy should be used to reduce the myospasm because too frequent injection can be injurious to the muscle.‘6 Transcutaneous electrical nerve stimulation. The use of transcutaneous electrical nerve stimulation (TENS) is based on the concept that stimulation of the cutaneous branches of the fifth nerve creates an inhibitory effect on the trigeminal spinal tract nucleus and thereby not only reduces awareness of pain but also helps indirectly to induce muscle relaxat ion.:‘, ” Patients are treated by placing the electrode directly over the area of most discomfort (care in avoiding main branches of the facial nerve will reduce the twitching effect). Therapy sessions last 30 minutes and should be repeated daily. Patients can be taught to use portable units at home and may then perform several treatments each day. Analgesics may be used to aid in further reducing periods of discomfort between sessions. Final explanation

of the problem

When patients with MPD syndrome begin to show improvement of their symptoms and have gained confidence in the doctor’s ability to deal with their problem, it is advisable to discuss with them the relationship between stress and muscular pain-dysfunction symptoms. Five concepts should be presented to the patient in this discussion. First, they must realize that MPD syndrome is a psychophysiologic disease. Second, they must be made to understand that this does not imply that their symptoms are imaginary, but that psychologic stress can cause physical disorders. The gastric ulcer is another example of a psychophysiologic disease that is easily understood by the patiem. Third, they must understand that stress can be related to pleasant as well as unpleasant life situations. Realizing this often makes it easier for pa.tients to identify stress in their lives. It is not essential that the clinician be told about the patient’s problems; what is important is that the patient identifies them and makes an effort to cope with them in a healthy manner. Fourth, the patient should be told how stress can result in centrally generated increases in muscle activity and pa.rafunctional habits such ;IS clenching and grinding of the teeth, and how this ieads to muscle fatigue, spasm, pain, and dysfunction. Finally, patients should be made aware that it may not be possible to provide a permanent cure for the problem, but that they can learn to manage it in a satisfactory manner by controlling stress and by using the recommended forms of simple therapy at the first sign of recurrent symptoms. Psychologic

counseling

Each indivildual’s reaction to stress is related to the state of his emotional health. Most pa.tients are able to 81

LASKIN

Phase I (24 wke) Accurate diagnosis Initial explanation Home therapy Medications

Symptoms

eliminated

BLOCK

1

I

I

I

AND

Phase cut therapy Final explanation Instructions for self-management Follow-up appointment

4

Symptoms

persist

Symptoms Continue

home therapy

Symptom,5

persist

L

I

I

I

I

I

Phase III (4-6 wks) Continue home therapy and medications Reevaluate splint Initiate physical therapy Initiate relaxation therapy

Symptomf

eliminated

and medications

Symptoms

eliminated

I

persist

*I

1 Psychological counseling I

1

Consultation

Referral

to center

Fig. 2. Management of MPD syndrome. understand the relationship of stress to physical illness, can identify stressful situations in their lives, and are able to cope effectively with these stresses once an explanation has been provided. A few patients, however, either are unable to recognize stressful conditions or are unable to cope with them in an appropriate manner. There are also some who have sufficient psychological gain from their illness to consciously or unconsciously not wish to get well. Such patients will be refractory to all forms of treatment. Referral of these individuals to a qualified psychologist or psychiatrist for counseling is in order.29s30During this time, however, the dentist should also continue treatment so that the patient does not get the impression that the problem has only a psychological component. Specific

treatment

plan (Fig. 2)

Once a definitive diagnosis of MPD syndrome has been made, the patient begins the first phase of therapy. In mild cases this period, which can last from 2 to 4 weeks, involves an initial explanation of the problem and the initiation of therapy at home. In more severe cases, an analgesic drug and a muscle relaxant are added to the regime. If the patient responds favorably, first the 82

analgesic and then the muscle relaxant are discontinued. Depending on the history of when the symptoms are worse, the drugs are initially decreased either at night or during the daytime. Home therapy is also gradually eliminated. The patient is given a full explanation regarding suspected etiology of the problem and instructions for further self-management. The patient should be told to return for care if symptoms recur and cannot be quickly controlled by the previously used procedures. In addition, a specific appointment for future follow-up should be given. If the initial therapy fails and reevaluation confirms the original diagnosis and indicates that the patient has been compliant, treatment is escalated to the second phase, which consists of the introduction of a splint in addition to continuation of the previous treatment modalities. This phase can last as long as 4 weeks. If the regimen is successful, medications are gradually reduced and then stopped, and use of the splint is also gradually eliminated. If the patient’s symptoms had been worse in the morning upon awaking, the splint is now worn only at night; if the symptoms had increased as the day progressed, the splint is worn only in the daytime. Unless the patient is engaging in excessive parafunctionJULY 1966

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SYNDROME

al activity while asleep, it should be possible to gradually eliminate use of the splint entirely. Bruxism patients, however, may need to continue using the splint indefinitely in order to remain asymptomatic. Before dismissal, the same instructions given to those successfully managed in the first phase of treatment are given to these patients. Most patients will respond favorably to the second phase of therapy; for those who do not, however, further escalation of treatment is indicated. In the third phase of treatment, which may last from 4 to 6 weeks, the splint should be reevaluated to be sure that it has been properly adjusted to the occlusion and that the correct vertical opening has been established. If these procedures fail, the anterior splint can be converted to provide full occlusal coverage. Although the splint may not prevent clenching, it does provide greater stability for the mandible. Physical therapy and relaxation therapy are introduced, and home therapy and medications are continued. If the symptoms subside, medications are stopped first, then the physical therapy, and then the use of the splint. Finally, the restrictions of home therapy are discontinued, but the patient may need to continue practicing his relaxation technique for an indefinite period. The same final explanation and instructions described for patients successfully treated in phase one are given before dismissal. If all of the previous approaches fail, and there is no question about the diagnosis, psychologic counseling should be recommended. If there is doubt about the prognosis, the patient should first be referred for appropriate consultation and reevaluation. Possible consultants may include the oral and maxillofacial surgeon, the neurologist, and the otolaryngologist. Another alternative is to refer patients with recalcitrant MPD syndromes to a TMJ center or pain clinic because they generally require a multidisciplinary approach for successful management. SUMMARY The successful management of patients with MPD syndrome is dependent on establishing an accurate diagnosis and using proper therapy based on an understanding of the etiology of the disorder. Establishing an accurate diagnosis is accomplished by taking a careful history, doing a thorough examination, and having a knowledge of the various other conditions that can produce signs and symptoms similar to those of MPD syndrome. Using proper therapy is related to recognition that MPD syndrome is a stress-induced psychophysiologic disease originating in the muscles of mastication and not an organic disease arising in the temporomandibular joint. Thus, therapy should be directed at reducing stress, relaxing tense jaw muscles, and creating an awareness by the patient of the causes of the problem, THE JOURNAL

OF PROSTHETIC

DENTISTRY

rather than at analyzing occlusion, measuring joint spaces, and producing irreversible structural changes in the dentition and the articulation. Because good results can be achieved with these uncomplicated, reversible forms of therapy,3’, 32it is important that the clinician does not succumb to an unproven fad or use of an irreversible procedure that will not achieve better results. REFERENCES 1. Laskin DM: Etiology of the pain-dvstunt ira,n ryndrorne. J Am Dent Assoc 79:147, 1969. 2. Greene CS: Myofascial pain-dysfunction :;yndrome. ‘l’he evolution of concepts. In Sarnat BG, Laskin Dhl, eds: The Temporomandibular Joint, ed 3. Springfield. Ii! 1979, Charles C Thomas, Pub], pp 277-288. 3. Yemm R: Tmemporomandibular dysfunction .md masseur muscle response to (experimental stress. Br Dent J 127~508, 1969, 4. Yemm R: A comparison of the electrical actwitv of masseter and temporal muscles of human wbjrrts durincr vxperimcntal stress. Arch Oral Viol l&269, 1971. 5. Carlsson GE, Magnusson T, Wedel A. SCI wry of panents seen at a department of Stomatognathlc Physiiv!oc?;v,Swed Dent J 69:115, 1976. 6. Butler JH. Folke LE, Brandt CL.: A desc->pi\e survry of signs and symptoms associated with the myofasc~al pain-dvsfunction syndrome. J Am Dent Assoc 9Oz62.5,f97!1. 7. Helms CA, Katzberg RW, Manzione JV: Computed tomography. In Helms CA, Katzberg RW, Dolw:tk MF, eds: Internal Derangements of the Temporomandibular Joint. San Francisco, 1983, Radiology Research and Education boundation. 8. Goldstein HA, Bloom CY: Detection of deqcnerative disease of the temporomandibular joint bv bone stin~ircr,~phy. J Nwl Med 21:928, 1980. 9. Greene CS, Laskin DM: Meprobamate therapy for the myofascial pain-dysfunction (MPD) syndromt: A double-blind waluation. J Am Dent Assoc 82587, 1971 10. Greene CS. Laskin DM: Splint therap\ I’OI thr myofascial pain-dysfunction (MPD) svndromr I\ ~miwtalive study. J Am Dent Assoc 84642, 1972. 11. Goodman P, Greene CS, Laskin DM: Response of patients with myofascial pain-dysfunction syndrome to mock equilibration. J Am Dent Assoc 92:755, 1976. 12. Dohrmann II, Laskin DM: An evaluation of rlcctromyographic biofeedback in the treatment ot myofasri.-11 pain-dysfunction syndrome. J Am Dent Assoc 96:656. 197?,. 13. Laskin DM, Greene CS: Influence of the doctor-patienr relationship on placebo therapy for patient< wirh rnyofascial paindysfunction (MPD) syndrome. J Am I !cn~ Assoc 85:892, 1972. 14. Greene CS: Myofascial pain-dysfunction syndrome: Nonsurgical treatment. In Sarnat BG, Laskin DM, editors: The Temporomandibular Joint. ed 3. Springfield. I I 1’179, Charles C Thomas, pub], pp 315-334. 15. Greene CS, Laskin DM: Therapeutic c-ltects of diazepam (Valium) and sodium salicylate in myofw ial pain-dysfunction (MPD) patients. 1972 (IADR abstr No. IQ?). 16. Gessel AH: Electromyographic biofeedback :md tricyclic antidepressants in myofascial pain-dysfunction syndrome: Psychological predicators of outcome. J Am Dent Awrc 91:1048, 1975. 17. Kraus HT: Muscle tension and the trmpl)r~)mandibular joint. J PROSTHET DENT 13:950. 1963. 18. Lehman .JF. De Lateur B~J, Warrw (‘r ;. Stonebridge JB: 83

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Heating of joint structures by ultrasound. Arch Phys Med Rehabil 49:28, 1968. 19. Eisen RG, Kaufman A, Greene CS: Evaluation of physical therapy for MPD syndrome patients. J Dent Res 63(Special issue):344, 1984. 20. Carlsson SG, Gale EN, ohman A: Treatment of temporomandibular joint syndrome with biofeedback training. J Am Dent Assoc 91:602, 1975. 21. Gessel AH, Alderman MM: Management of myofascial paindysfunction syndrome of the temporomandibular joint by tension control training. Psychosomatics 12:302, 1971. 22. Olson RE, Greene CS, Solar S: Comparison of two relaxation methods for the treatment of MPD syndrome. J Dent Res 59(Special issue A):518, 1980 (Abstr No. 996). 23. Price A, Stallard RE: Hypnotic therapy for MPD. J Dent Res 55128, 1974 (Abstr No. 296). 24. Tarte JS, Spiegel H: The role of hypnosis in the treatment of craniomandibular dysfunction. In Gelb H, editor: Clinical Management of Head, Neck and TMJ Pain and Dysfunction. Philadelphia, 1977, WB Saunders Co, pp 401-442. 25. Travel1 JG, Simons DG: Myofascial pain and dysfunction: The trigger point manual. Baltimore, 1983, Williams & Wilkins co. 26. Benoit PW, Belt WD: Some effects of local anesthetic agents on skeletal muscles. Exp Nemo1 34:264, 1972.

27.

28. 29.

30. 31.

32.

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BLOCK

Block SL, Laskin DM: The effectiveness of transcutaneous nerve stimulation (TNS) in the treatment of unilateral MPD syndrome. J Dent Res 59(Special issue):519, 1980 (Abstr No. 999). Gold N, Greene CS, Laskin DM: TENS therapy for treatment of MPD syndrome. J Dent Res 62~244, 1983. Pomp AM: Psychotherapy for the myofascial pain-dysfunction (MPD) syndrome: A study of factors coinciding with remission. J Am Dent Assoc 89:629, 1974. Marback JJ, Dworken SF: Chronic MPD, group therapy and psychodynamics. J Am Dent Assoc 90:827, 1975. Greene CS, Laskin DM: Long-term evaluation of conservative treatment of myofascial pain-dysfunction syndrome. J Am Dent Assoc 89:1365, 1974. Greene CS, Laskin DM: Long-term evaluation of conservative treatment of myofascial pain-dysfunction syndrome: A comparative analysis. J Am Dent Assoc 107:235, 1983.

Reprint requests to: DR. DANIEL M. LASKIN MEDICAL COLLEGE OF VIRGINIA SCHWL OF DENTISTRY

Discriminative ability of the TMJ Scale: Age and gender differences T. F. Lundeen, D.M.D., MS.,* S. R. Levitt, M.D., Ph.D.,** and M. W. McKinney, University of North Carolina, School of Dentistry, and North North Carolina Central University, Durham, N.C.

T

he concept of a single TMJ syndrome of temporomandibular joint disorder has been replaced with a series of diagnostic categories such as internal derangements, arthritic disorders, and muscle hyperactivity disorders. These diagnostic categories need to be carefully defined on the basis of clinical symptomatology and pathogenesis. A standardized assessment method is necessary to make useful comparisons between the different disorders as well as between different studies.’ Reliable and proved testing methods that provide standardized and *Associate Director, Pain Program, and Associate Professor, Department of Operative Dentistry, University of North Carolina, School of Dentistry. **Clinical Assistant Professor, Department of Psychiatry, University of North Carolina, School of Medicine, and Pain Resource Center, Inc., Durham, N.C. ***Professor, Department of Public Administration, North Carolina Central University, and Pain Resource Center, Inc., Durham, N.C. 84

Carolina

Memorial

Hospital,

Chapel

Ph.D.*** Hill,

N.C.,

and

quantitative methods for patient assessment have been developed in other disciplines, especially clinical psychology. We have used these methods to develop a diagnostic tool called the TM J Scale.‘, * The TM J Scale is a 974tem questionnaire developed specifically for the assessment of TMJ disorders (Pain Resource Center Inc., Durham, N.C.). The questionnaire produces scores on 10 clinically important symptom scales associated with TMJ disorders. There are five physical symptom scales, three psychosocial scales, a non-TMJ disorder scale, and a global scale. The five physical symptom scales include pain report, palpation pain, malocclusion, joint dysfunction, and range of motion limitation. The psychosocial scales include psychologic factors, stress, and chronicity. The non-TMJ scale is designed to detect the presence of other oral and facial problems. The global scale is a general predictor of the presence of a TMJ disorder. Each of the symptom scales functions independently. The global scale was JULY 1986

VOLUME

56

NUMBER

1