Pain in the masseter muscle

The chewing muscle (Musculus masseter) is considered one of the strongest muscles in the human body in terms of strength, despite its rather small size. It is capable of developing a force of up to 70-75 kilograms, taking part in chewing food, swallowing, articulation, yawning, and also in facial expressions of emotions. Pain in the chewing muscle is its dysfunction caused by various reasons, the most important of which is constant, almost round-the-clock load, resulting in pathological muscle hypotrophy or spasm.

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Causes of pain in the chewing muscle

Recently, doctors have begun to pay well-deserved attention to muscle diseases in general, including myalgia of the face, as well as pain in the masticatory muscle within the framework of myofascial pain syndrome of the face or myofascial prosopalgia, which is being very actively studied.

The first detailed description of facial pain as a symptom complex, including joint and muscle manifestations, was given in the 1930s by American doctors Goodfried and Costen. A little later, the concept of "bruxism" was introduced, which became the starting point for explaining the causes of pain in the masticatory muscle.

Despite almost half a century of history, the etiology of facial muscle syndromes has not been fully studied, an example of which is the contradiction in the various terms and the lack of a single classification of causes. Pain in the masticatory muscles can be called myofascial prosopalgia, craniomandibular dysfunction, muscular-tonic facial syndrome, and so on.

Currently, all previous studies are being reviewed more thoroughly, it is noteworthy that the most promising hypothesis is about the myofascial cause of the pain symptom in the masticatory muscle. Although many doctors still consider the cause of pain in the Musculus masseter (masticatory muscle) to be the collective term TMJ syndrome (temporomandibular joint syndrome). There are other, no less reasoned studies, confirmed by the results of diagnostic examinations in the field of mental disorders, in the category of ENT pathologies, vertebrogenic dysfunctions.

Sometimes a painful symptom in the masticatory apparatus can have a very simple explanation. If a person is a pessimist by nature, constantly frowns, gets angry, he unconsciously clenches his jaws and this becomes a habit. It would seem that this character trait is not associated with a muscle disease, but quite often psychological reasons are the basis for many diseases in principle, including in the face.

Also, professional activity, especially sports, can cause tension. Divers, scuba divers who have to squeeze the mouthpiece, heavy weightlifters who lift weights in a roar are at risk of TMJ damage and pain in the chewing muscle.

Possible factors and causes of pain in the area of the masticatory muscles are very diverse and may be as follows:

• Dental treatment, manipulations.
• Malocclusion (occlusion, teeth closure).
• Dysfunction, degenerative process in the temporomandibular joint, TMJ syndrome, Costen syndrome.
• Maxillofacial injuries.
• Osteochondrosis of the cervicothoracic spine.
• Anatomical abnormalities of the spine, asymmetry of the shoulder girdle, uneven leg length (shortening).
• Stressful situations.
• Psychogenic factor, hysteria.

Practicing doctors claim that the leading cause of hypertonicity of the masticatory muscle is a violation of occlusion, the closing of the teeth, which in turn is provoked by the following factors:

• Poor quality prosthetics, orthodontic therapy.
• Chronic psycho-emotional stress, especially in people working in responsible positions.
• Neurotic diseases.

Occlusion dysfunctions lead to reflex hypertonicity of the facial muscles, the most vulnerable in this sense is the chewing muscle. If the bite is not corrected in a timely manner, and in 75-80% of cases this happens, a secondary syndrome develops - myofascial, while the function of the TMJ, facial muscles is impaired, and a persistent psychovegetative symptom complex gradually forms. The patient can visit doctors for a long time, presenting purely neurological complaints, the treatment is ineffective, since the symptoms of pain in the face, in the chewing muscle were not determined with due accuracy.

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Symptoms of pain in the chewing muscle

It should be noted that the chewing muscles, like other facial muscles, are characterized by the fact that they do not have fascia, perhaps this causes the atypical nature of the pain - it is unbearable, very intense and causes a lot of suffering to a person. In addition, pain can be reflected in an atypical place - in the back of the head, upper neck, near the ear. Therefore, it is extremely important to identify the exact characteristics that the symptoms of pain in the chewing muscle have.

Myofascial pain syndrome in the facial area develops according to a certain pattern:

• The provoking factor causes tension, contraction of the masticatory muscle; if the factor is not eliminated, hypertonicity becomes permanent.
• Chronic muscle tension progresses to the spasm stage, which is often clinically manifested as trismus.
• Constant pain and spasms exhaust the muscle, it becomes weak, its tone is significantly reduced.
• Against the background of hypotonia, weakness of the affected masticatory muscle on the opposite side, new muscle tension develops as a compensatory functional phenomenon. The muscle involved in the myofascial process does not hurt at first.

The most typical signs of pain syndrome of the masticatory muscle include the following manifestations:

• Pain in the area of the chewing muscle, increasing with any movement of the lower jaw.
• Limitation of the volume of movement of the lower jaw to 10-20 millimeters between the teeth.
• The sensation and sound of a click in the joint, crepitus.
• Typical zigzag deviation of the jaw (in the shape of the letter S) - forward or to the side.
• Bruxism (grinding of teeth), especially at night.
• Painful sensations during muscle palpation.
• Tension, hypertrophy of the muscle, determined by palpation.
• Facial asymmetry is possible.

Symptoms of pain in the chewing muscle can be felt in the upper jaw, in the area of the superciliary arches, in the sinuses, and also in the ear, often in the form of an annoying, constant “ringing”.

Diagnosis of pain in the masticatory muscle

The masticatory muscles of the face are the only group of muscle tissue in this area that can exhibit all the typical, diagnostically reliable myofascial pains. This is due to the fact that the masticatory muscle bears an extremely intense static and kinetic load, which in turn creates all the conditions for the formation of characteristic myofascial pain bundles - trigger zones. However, diagnosing pain in the masticatory muscle can be difficult, since the patient can be treated for a long time by a neurologist, psychotherapist, ENT doctor, the symptoms are smoothed out, often the clinical picture is significantly distorted up to the development of such a complex syndrome as oromandibular dystonia of the face (focal muscular dystonia). Therefore, a very important and dominant method after the initial survey and examination is palpation of the facial muscles. In a clinical sense, the following can be considered signs that determine myofascial syndrome:

• Patient posture and head position.
• Range of motion of the neck.
• Facial expressions (facial muscles, symmetry).
• Muscle condition during conversation.
• Swallowing reflex and muscle condition during swallowing.
• Presence or absence of blepharospasm.
• Eye closure reflex (corneal reflex).
• The state of the muscles when clenching the teeth and closing the jaw.
• Activity of movement, range of motion of the lower jaw.
• The distance between the teeth (incisors) when the mouth is open.
• Trajectory of movement of the lower jaw in relation to the upper jaw (S-symptom).
• Bechterew's reflex (mandibular reflex).
• Mimic activity of the brow ridges.
• Condition of the facial nerve (Chvostek's symptom).
• Determination of possible biomechanical disorders of the spine, which are manifested visually – scoliosis, asymmetry of the shoulder girdle, other deformities.

The main diagnostic method, palpation, reveals localized tense areas, often in the form of trismus. The characteristic features of trigger myofascial points are reflected pain sensations within the spasmodic zone, the "jump" symptom, when the patient shudders during palpation of the muscle. Palpation is performed from the outside of the face, as well as inside, from the side of the mucous membrane, the three-phalangeal method has been considered the gold standard of palpation for many years.

When examining the masticatory muscle, tension points give reflected pain downwards, into the jaw, into the teeth, less often upwards – into the forehead, into the area of the superciliary arches, into the upper gum, into the temple. If the muscle is toned in the deep layers, the symptom may manifest itself in the ear, legs not as pain, but as sound, noise.

In addition to palpation, diagnosis of pain in the masticatory muscle includes the following stages of examination:

• Measuring the bite – occlusiogram.
• Measuring the dynamics and statics of the bite.
• X-ray of the TMJ (temporomandibular joint).
• OPTG – orthopantomogram or panoramic x-ray of the jaw.
• Electromyography of the masticatory muscle and other muscles of the masticatory apparatus, and, if necessary, the facial muscles as a whole.

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Treatment of pain in the chewing muscle

Treatment of pain in the masticatory muscle, as well as therapy for any other type of myofascial syndrome, depends on many factors, but primarily on the results of diagnostics. Quite often there are cases when pain in the facial muscles, in the masticatory apparatus, has a polyetiology, for example, occlusion disorder in combination with TMJ dysfunction, aggravated by inflammation of the facial nerve. This entire complex is accompanied by a depressive state, pathologically provoking new spasms of the masticatory muscles. In addition, the cause or secondary symptom may be spasm of the neck muscles and persistent headache - TH (tension headache).

The doctor faces a difficult task – where to start treatment? Only a thorough analysis of the etiological factors and determination of their significance in the pathogenesis of myofascial pain can give the correct direction to the therapeutic strategy.

Complex treatment may begin with relieving the main pain symptom, but in general it includes the following actions:

• Correction of abnormal occlusion (bite), restoration of normal occlusal height.
• Dental prosthetics if necessary.
• Avoiding any stress-provoking factors – chewing hard food, chewing gum, the habit of chewing on a pencil or pen, and others.
• The identified trigger pain points are subjected to anesthetic blockade (novocaine, dry puncture).
• Post-isometric therapy, relaxation of toned muscles.
• Gentle manual facial massage.
• Physiotherapy procedures.
• Acupuncture.
• Compresses with dimexide on the temple area, in the area of the chewing muscle.

Drug treatment of pain in the masticatory apparatus may include the prescription of muscle relaxants (mydocalm, baclofen, tizanidine), antidepressants, sedatives, tranquilizers. Less frequently, NSAIDs are prescribed - non-steroidal anti-inflammatory drugs, much more effective is the intake of a vitamin complex, including the entire group of vitamin B.

How to prevent pain in the chewing muscle?

Obviously, prevention of pain in the masticatory muscle, based on the main causes, consists of oral care and regular dental check-ups. Emotional balance and mental health also play an important role in reducing the risk of pain, which is especially relevant in our age of speed and stressful situations.

Also, the possibility of developing hypertonicity in the masticatory muscle is eliminated by getting rid of banal habits - gnawing pencils, pens, these actions that have become commonplace are completely unnoticed by people, they are performed unconsciously and constantly. Chronic load on the masticatory apparatus only worsens, in addition, such habits themselves are signs of neurotic disorders and a reason to take care of your mental balance.

If the pain symptom has developed, it has been persistently treated, for prevention and reduction of the risk of relapse it is necessary to follow a certain diet, excluding the use of coarse, hard food. Each dish should be chewed thoroughly, and to reduce the load on the muscles it is necessary to cook food in a steamed, crushed form. Regular facial massages also give a good effect, especially with night bruxism. Relaxation techniques with the help of autogenic training, periodic intake of herbal soothing infusions, homeopathy will help to avoid pain, muscle spasms.

Pain in the masticatory muscle of the face is a common symptom that is often not diagnosed and treated in a timely manner. Self-medication, delaying a visit to the doctor, especially if it is a dentist, can lead to chronic headaches, depression, aesthetic problems - facial asymmetry and a decrease in the quality of life in general. In order not to give pain a single chance and "save face" in every sense of this expression, you need to monitor the condition of the muscular system, avoid excessive tension of the facial muscles and not be afraid to seek help from a doctor. The sooner the symptom is detected, the faster and more successfully its treatment will be.