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Temporomandibular joint (TMJ) disorders in children are relatively
rare. They can be divided into extra-articular and intra-articular types,
which can occur alone or together.
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The most common TMJ problem is myofascial pain, which is extra-articular
in origin. The muscles of mastication can have a high resting tone,
and they are often in spasm because of muscle hyperfunction or parafunction
due to daytime and nocturnal jaw clenching (bruxism). Myofascial
pain is more common in the morning and is often associated with
a decrease in function. Related symptoms include headache, ear pain,
joint noises, closed or open lock, difficulty chewing, and limited
mouth opening.1
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Intra-articular TMJ disorders that result from an abnormal relationship
between the condyle and mandibular disk are also often associated
with symptoms of myofascial pain.2 Spasm of the
lateral pterygoid muscle, which inserts into the disk, can displace
the disk anterior to the condyle.3 Anterior displacement
with reduction occurs when the condyle moves under the displaced
disk into a normal relationship and the opening movement occurs
without impediment. This is usually associated with a midopening
click, which can be audible and/or palpable. Anterior displacement
without reduction is often the result of adverse loading of the
TMJ or sudden trauma to the joint. When there is tearing and scarring
of the retrodiscal tissues, the displacement is likely to be permanent
and results in the disk losing its shape and becoming rounder, blocking
the condyle from normal movement. When this occurs, the patient
can only rotate, which limits opening to the 25-mm range.
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Treatment of myofascial pain is focused on diminishing muscle
hyperactivity. The goals of therapy include eliminating behavior
that is noxious to the muscles and joints; decreasing the frequency,
duration, and intensity of pain episodes; providing support and
counseling about stress reduction and other psychologic concerns;
and establishing a functional and adequate jaw opening. Nonsurgical management
is used to treat myofascial pain, and most patients respond well
to this treatment.
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Some of the nonsurgical treatment modalities include a soft diet
with elimination of hard/chewy foods, thereby reducing
the loading forces on the joint and decreasing muscle activity.
Physical therapy to increase range of joint motion and muscle relaxation,
massage of the muscles of mastication, and cold or hot compresses
applied before and after exercises may also be helpful.4,5 Ultrasound
can deliver heat to a depth of about 5 cm, and when done in combination
with stretching, it can alter the elastic properties of connective
tissue.6
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Splint therapy with the use of a flat plane acrylic appliance
that fits onto the dentition and disoccludes the teeth and jaws
diminishes the loading forces on the discal tissue. Additionally,
the splint distracts the condyle slightly out of the fossa and reduces
pressure on the intracapsular tissues. Interrupting the normal proprioception
of the masticatory system reduces muscle activity.7,8 Splints ...