The Temporomandibular Joint And Internaldislodgementa. The temporomandibular joints (TMJ) are among some of the most frequently used joints in the body. b. it allowing us to talk, chew, yawn, swallow and sneeze. c. The two bones that form the TMJ are the mandible (jaw) located inferiorly, and the temporal bone of the skull (located more superiorly). d.The articular fossa. Between these two bony components is the joint disc or meniscus, which is made of cartilage. This disc allows for smooth function and aids as a cushion between the condyle and the articular fossa.Ligaments support and stabilize the disc and condyle and together with the surrounding muscles allow for proper movement of the lower jaw during functions such as chewing,

speaking and swallowing.

fig2

Tmj are located on both sides of the face in front of the ears, connecting the jawbone (mandible) to the skull (temporal bone). They're the most complicated joints in the human body, providing rotation (pivoting) movement like all joints, as well as sliding movement, called translation. It serve as shock absorbers, protecting the bones from hitting each other.

MOVEMENT OF TMJ:Both TMJ must work in coordination in order to allow normal movement to occur. The TMJ allow us to open and close the mouth, protrude, retract, and laterally move the jaw (mandible) right and left. Normally, opening of the mouth should be 35-40mm.

Muscles Acting on the TMJ are muscles of mastication, allowing the mandible to move for the purpose of chewing and speaking. The primary muscles involved are the following: temporalis, masseter, medial pterygoid, and lateral pterygoid . The muscles of each TMJ must work together. Dysfunction occurs

when the Muscle are out of the synchrony leading to muscle spasm, pain and inflammation of the TMJ. When in a state of muscle imbalance, subluxation of the joint is also possible.

Nerves present around the tmj:

Temporomandibular Joint Dysfunction:

The mostcommon dysfunctions associated with the tmj inflammation,muscle imbalances, hypomobility, and hypermobilty. The synovium, retrodiscal tissue and the capsule are some of the tissues that can become inflamed in the TMJ.

Possible causes for TMJ dysfunction:

1. Trauma to the joint–blow to the jaw or head

2. Excessive stress to the joint from gum chewing, fingernail biting, yawning, chewing on a pen, chewing on ice, and grinding teeth

3. Jaw abnormalities, missing teeth, poor bite (malocclusion) 4. Resting the head in the hand 5. Arthritis of the TMJ 6. Dislocation of the disc 7. Myofascial pain dysfunction 8. Postural abnormalities, especially with a forward head posture 9. Whiplash injury 10.Prolonged mouth and upper respiratory breathing 11.Thumb sucking 12.Ligamentous laxity 13.Birth/Congenital trauma

 

Common signs and symptoms of TMJ dysfunction :1.Clicking or popping with o Pain at rest or with opening/closing of jaw

2.Decreased ability to open the jaw (hypomobility)

3.Neck pain

4.Tooth sensitivity

5.Dry or burning sensation in mouth

6.Uncomfortable bite

7.Forehead or temple headache

8.Buzzing or ringing in ears

9.Hearing loss

Self-care for Management of Symptoms:

1. Habit Modification: Try to avoid the activity that is causing the increased stress to the joint such as nail biting, gum chewing, and ice biting.

2. Diet Modification: Eat a diet of soft foods in addition to chewing evenly. 3. Pharmacological: Anti-inflammatory medications such as aspirin or ibuprofen

can help to decrease pain and inflammation. 4. Hot compresses: Use a washcloth soaked in warm water or a commercial moist

hot pack over the area of pain or tenderness. This will help reduce any muscle spasm which may be experiencing.

5. Dental Appliances: some type of intra-oral splint, nightguard or other appliance. This may help to stabilize the TMJ so the muscles, teeth, and joints work together without adding additional strain to the TMJ.

6. Cold packs: These can be used to help reduce any swelling, pain and muscle spasm.

7. Stress Management: Stress is a common contributing factor to TMJ dysfunction. In this, condition deep relaxation training, breathing, meditation or biofeedback are of great benefit.

8. Posture: A forward head posture is a big contributor to TMD. Try to practice good posture, especially when sitting for long periods of time.

9. Massage: Try to gentle massage over and around the area of discomfort. This helps in relieving any muscle spasm.

When to seek professional help? If your symptoms last for more than 2-3 weeks, you should seek professional assistance. For a true diagnosis of TMJ dysfunction, a comprehensive history and physical exam along with other diagnostic procedures such as a x-ray and lab

tests are necessary.CT and MRI scan are taken.

∙TMJ disorders are separated into two main categories based on the anatomic origin of the problem: 1.Articular disorders: include the articular surface, intra-articular disk, or articulating bones. 2.Masticatory muscle disorders: are problems within the muscles surrounding the TMJ.

TMJ Evalution and examination: In order to make a proper diagnosis, information is obtained in three ways.

1. Medical History2. Clinical Examination3. Radiographic Examination.

Medical history: This examination begins with a detailed review of the history of the presenting problem. This includes the onset, duration, location and character of the pain or dysfunction.

Clinical examination: A physical examination involving the head, neck and TMJ regions would follow to further evaluate the degree of dysfunction.

Radiographic examination:In some cases it is necessary to order a specific test to confirm diagnosis of a TMJ disorder.

1.Imaging Tests: Imaging Tests help show parts of the face, neck and head that can't be seen during a physical exam. 2.CT Scan: Shows slices of the jaw joint. The images can be used to diagnose arthritis, injuries and fractures. 3.Magnetic resonance imaging (MRI): Creates images of soft tissue, muscles, disc and ligaments of the jaw and head. 4.Panoramic x-ray: provides a wide view of the jaws, including the teeth and their roo

orthopantomogram demonstrating bilateral temporo-mandibular joint dislocation (red circle).

Tmj mild dislocation

Indications for surgery: FAILURE TO RESPOND TO CONSERVATIVE MEASURES:

¨ Internal joint derangement

¨ Degenerative and inflammatory joint disease

¨ Recurrent dislocation

¨ Ankylosis

¨ Fracture dislocation of neck of condyle

¨ Neoplasia

Chronic recurrent dislocations

In the long term, however, surgery in the form of enlarging the eminence by osteotomy, or grafting bone to stop the condyle slipping over it. A capsulorrhapy (tightening the capsule) can also be of help to such patient

DIAGNOSIS:

All TMJ Dysfunction patients should be divided into two basis

classifications. These are internal derangement cases and

external derangement cases.

The Internal derangement means that there is a mechanical

problem within the T.M.J. capsule.

The external derangement indicates that there is a problem within

the muscle-skeletal system outside of the T.M.J. capsule.

Internal Derangement:it can be 2 types 1.slef reducing

2.non reducing.

1.self reducing internal derangement:The self-reducing anterior

displacement of the meniscus means that as the patient begins to open

their mouth the mandibular condyle is trapped distal to the meniscus

relative to the articular surface of the glenoid fossa. As the patient

continues to open, tension builds within the joint capsule. At some point in

the opening process, the tension within the capsule is sufficient to pull the

head of the mandibular condyle into its correct position upon the

meniscus. From that point onward, the T.M.J. function is normal because

the condyle and meniscus are operating correctly as a unit.

There are two basic clinical observations that confirm the diagnosis of a

self-reducing anterior displacement of the meniscus.

1.First, there is an opening deviation of the mandible ipsilateral to the

joint problem. As the condyle relocates itself properly upon the meniscus,

the mandibular deviation returns to normal. When the problem is bilateral,

the opening deviation of the mandible is sigmoid deviating from side to

side and returning to correct alignment, depending upon which joint

complex returns to normal function first.

2.The second very diagnostic clinical characteristic is an audible

pronounced sound within the joint capsule which usually presents itself as

a “click”. This sound is generated by the mandibular condyle relocating

itself correctly upon the meniscus.

The self reducing anterior displacement of the meniscus will have a full

range of normal motion. Very simply, at some stage in the opening cycle,

one or both mandibular condyles return to their correct relationship with

the meniscus, and from that point onward, function is totally normal.

2.non reducing internal derangement:

If the damage to the joint complex continues, most patients advance into

what is called a non-reducing anterior displacement of the meniscus. This

means that no matter how hard the patient attempts to open their mouth,

or manipulate their mandible, the mandibular condyles remain trapped

distal to the meniscus.

The patient will have an opening deviation of the mandible ipsilateral to

the problem with no return to a normal skeletal midline. When the

problem is bilateral, there is no significant opening or closing deviation of

the mandible, but the patient will have limited vertical opening.

Another key diagnostic test is to align the skeletal midlines and check the

patient´s lateral motion. There will be limited lateral excursion to the side

contralateral to the non- reducing anterior displacement of the meniscus.

There is no joint noise when the patient has the nonreducing anterior

displacement of the meniscus since the condyle is unable to “snap” into

its correct position on the meniscus.

The non-reducing anterior displacement of the meniscus is usually best

treated with a pivot-splint. The pivot splint must be placed upon the lower

arch.

PHARMACOLOGIC INTERVENTION: Acetaminophen and non-steroidal anti-inflammatory drugs can help with acute and chronic pain. For muscle spasm and chronic bruxism, muscle relaxants or benzodiazepines may be necessary if conservative relaxation techniques fail.

INTRA-ARTICULAR INJECTIONS

Intra-articular injections of the TMJ with local anesthetics or corticosteroids can be used for the treatment of inflammation within the TMJ capsule. Intra-articular injection should only be used for severe acute exacerbations or after conservative therapies have been unsuccessful.

DENTAL OCCLUSION THERAPY

Dental occlusal splinting and permanent occlusal adjustment have been the mainstays of TMJ disorder treatment for years, although there is no clear evidence that malocclusion of the upper and lower teeth causes TMJ pain. Two main types of splinting are available: occluding and nonoccluding.

PreventionTMJ dislocation can continue to happen in people with loose TMJ ligaments. To keep this from happening too often, dentists recommend that people limit the range of motion of their jaws, Conservative surgical treatments can help to prevent the problem from returning. Some people have their jaws are wired shut for a period of time, which causes

the ligaments to become less flexible and restricts their movement. In certain cases, surgery may be necessary. One procedure, called an eminectomy, removes the articular eminence so the ball of the joint no longer gets stuck in front of it. General TMJ (Disorder) TreatmentDentists use a variety of treatment modalities which may be divided into Phase I, Phase II and Phase III Therapy.Phase I Treatment. Phase I treatment for TMJ is conservative treatment.. Generally, the use of an intra oral splint, sometimes medication is required.Phase II Treatment. Phase II treatment is, by definition of the American Dental Association, non-reversible, invasive therapy. This is done when the patient have been evaluated and released of Phase I treatment. Some of the recommendations are; adjustment of the occlusion (adjusting the "bite") which is done by painlessly filing each tooth until there is a precisely even and comfortable fit. It is rare but surgery of all types may be necessary and most certainly produce changes which can't be reversed. Therefore, it is most important that no one undergoes Phase II Treatment until a correct diagnosis is established and proven as the cause of the symptoms.Phase III Treatment. Phase III treatment is the long term management of a patient following successfully completing Phase I and Phase II treatment. Phase III (the maintenance phase) involves the use of a night time/stress splint. Regular personal TMJ therapy and cautious use of the jaw to avoid new and additional injury to the jaw joints and muscles.