TMJ and Causes of TMD

The temporomandibular joints are among the most utilized joints in the body, due to their prolonged use during chewing, talking, singing, yawning, etc. Jaw dysfunction (TM dysfunction) means that the lower jaw is not in its proper relationship to the upper jaw. This frequently results in a dislocation of the protective disc anteriorly as the lower jaw assumes a position further back than normal.

Some of the most common causes of TMD

Lower Jaw Too Far Back

• Deep dental overbite
• Upper front teeth tipped backwards
• Back teeth missing
  • Result: causes dislocation of the protective disc anteriorly

Unbalanced Muscles

• Clenching or grinding habits
• Bad posture

Trauma

• Automobile accidents
• Whiplash injury
• Intubation procedures in hospitals
• Trauma to the head or jaw

Condyles Too Far Back: The Main Cause of TMD

Normal Joint	Dislocated Jaw Joint - Disc Displaced Anteriorly

The temporomandibular joint is affected like no other joint in the body. Behind the condyle (top of lower jaw), there are several structures that affect the health of the jaw joint itself. One is the posterior ligament which acts as a rubber band to pull the disc backward during closing of the jaw. Like all joints, the TM joints contain a large amount of nerves and blood vessels that on a subconscious level give the brain information about the position and condition of the joint. When the jaw is closed, the disc, which has no feeling, acts as a shock absorber to prevent the nerves and blood vessels from being compressed. When the mouth opens and the condyle and the disc move forward, the blood vessels expand to fill the vacated space. When the condyle is pushed too far backwards in the joint, it can slip off the cartilage disc and into these nerves and blood vessels. When nerves and blood vessels are compressed, the whole structure is unbalanced, affecting the nerves, the ligaments and the muscles of the head, neck and face. This dislocated jaw causes pain and other symptoms, which affect health and a person's quality of life.

Dislocated Jaw Joint, Disc Displaced Anteriorly

The treatment of choice for a patient with a dislocated jaw due to the lower jaw (condyle) being positioned too far back would be to use a lower splint, orthotic or functional jaw orthopedic appliance to reposition the lower jaw forward.

Unbalanced Muscles

Unbalanced muscles can be a result of clenching or grinding of the teeth. If a muscle is overworked or becomes fatigued due to a structural imbalance, other muscles must compensate. This compensation causes the body to adjust to an abnormal postural state. Compensation means the body adapts to a state that is unhealthy. The body will start to experience symptoms on a mild level, such as occasional headaches. Slowly the symptoms start to occur on a more frequent level until eventually you are experiencing pain on a daily basis.

Whether you have a slightly displaced disc, a dislocated disc, unfavorable head posture or body posture, the abnormal forces and strain produced by tired, spastic muscles can refer pain into the neck, face or head. These muscle tension headaches can be so severe that they are confused with migraine headaches. Unfortunately, patients are often not examined for TMJ disorder and the "migraine" treatment works poorly.

The treatment for patients with migraine headaches is often the prescribing of pain medications such as Imitrex. This medication is ineffective in solving problems relating to dislocated jaw joints (TM dysfunction). Patients are advised to contact a dentist who utilizes appliances designed to reposition the lower jaw forward or to control parafunctional habits to try and solve the problem as early as it is diagnosed.

An overwhelming majority of patients who sustain whiplash injuries in motor vehicle accidents (MVA) also dislocated one or both temporomandibular joints at the same time without having impacted their face or head against the steering wheel, door column, windshield or other parts of the car.

Whiplash typically occurs if the head is thrown backward and forward while riding in a car that is hit from behind or the side. Extensive research has well documented the fact that most flexion-extension injuries occur following what is called "minor head injuries." This means that it is not necessary to suffer a fracture or even a direct head impact. In fact, most patients report that their head was simply snapped backward and forward or side to side. This motion causes damage to the muscles and ligaments which support the jaw joint. When these muscles and ligaments are injured, this can cause an anterior displacement of the protective disc and result in a dislocated jaw joint on one or both sides.

Intubation Procedures

Patients that undergo surgical procedures with general anesthetic are usually intubated through the mouth. Intubation is the procedure by which a tube is placed down the throat to keep the airway open during surgical procedures. Occasionally, the jaw can be dislocated during this procedure due to the forced opening of the mouth and the hyperextension of the ligaments and tissues in order to insert the tube. Some patients may experience clicking in the jaw, limited opening of the mouth, facial pain, and headaches post surgically. Those patients who have already been diagnosed with a TM disorder should advise the anesthetist that they wish to be intubated through the nose during any surgical procedure to prevent further damage to the joint and its surrounding structures.

Trauma to the head and jaw

A severe blow the head or the jaw can cause the disc to be dislocated due to the force of the impact on the jaw. Patients may experience swelling, limited opening and clicking in the joint. Patients with this acute injury should seek emergency treatment immediately to avoid further damage to the joint.

Food and drinks known to aggravate headaches for some patients

• Alcohol
• Tobacco
• Caffeine Coffee,tea, soft drinks, chocolate
• M.S.G. Flavor enhancer user to preserve foods
• Artificial Sweeteners Aspartame, Nutrasweet
• Vegetable Oil Fried or greasy foods should be avoided
• Milk and Cheese
• Nuts
• Raw Beans
• Pork

Treatment of TMD

Discussion and examination take place at the initial consultation appointment when the patient reports time of onset, duration and intensity of pain in the affected area. The examination explores the pattern of jaw movement to detect sounds and tenderness to gentle pressure.

Further diagnostic testing is indicated the presence of jaw joint dysfunction is suspected. Further testing is designed to properly diagnose the patient's problem and to try to reduce the signs and symptoms of the dysfunction. To determine if the lower jaw and the disc of the TM joints are in the correct position, the following diagnostic tests are used:

• Medical and Dental History as well as an examination of the teeth and the dental arches
• TMJ Health Questionnaire
  Patients are asked questions regarding possible TM dysfunction symptoms. If the patient answers "yes" to any of the symptoms and "yes" to clenching and bruxing, then further tests are required to confirm the presence of a jaw joint problem (TM disorder).
• Range of Motion
  Patients are checked for how wide they can open, slide left and right, move the jaw forward, and whether or not there is a deviation or deflection of the jaw upon opening. If there is a problem achieving normal range of motion, there is usually a structural problem within the joint.
• Muscle Palpation
  Excessive muscle contractions and trigger points indicate a problem with the chewing muscles of mastication. This causes the muscles of the head and neck to be sore when pressed by the dentist. This usually means that the lower jaw is not in the correct position.
• TMJ X-Rays
  TMJ x-rays are important to see if the condyles (top of the lower jaw bone) are too far back where they would be impinging on the nerves and blood vessels at the back of the socket where the jaw bone fits into the skull. In cases where the lower jaw is too far back, dentists find a significant reduction in the signs and symptoms of TM disorders when the jaw is repositioned forward with a splint or a functional orthopedic appliance.
• Computerized Joint Vibration Analysis: (JVA)
  This is specialized equipment used to take readings of the noises or vibrations occurring within the jaw joints upon opening and closing movements. The JVA is simply a 3-minute, non-invasive test where headphones are placed on both jaw joints and the patient is instructed to open and close six times. An abnormal or dislocated joint has distinctive vibrations which can be analyzed to help diagnose the seriousness of the problem.

There are basically 5 stages of disc displacement. Ideally, if there is a jaw problem you would hope that the patient is in Stage 1 or Stage 2 where the disc can be recaptured. If the JVA reveals that the patient is in Stage 3, 4 or 5, this is a much more serious problem and the prognosis is not as good for resolution of all the symptoms.

Our office has the knowledge and experience needed for proper, thorough diagnosis and treatment of temporomandibular joint dysfunction.

Treatment

Since the teeth, jaw joints and muscles can all be involved, treatment for this condition varies. Typically, treatment will involve several phases. The first goal is to relieve the muscle spasm and pain as well as establish normal range of motion of the lower jaw. Then, your dentist must correct the way the teeth fit together. Often a temporary device known as an orthotic or splint is worn over the teeth until the bite is stabilized. Permanent correction may involve selective reshaping of the teeth, building crowns on the teeth, orthodontics or a permanent appliance to cover the teeth. If the jaw joint itself is damaged, it must be specifically treated. Although infrequent, surgery is sometimes required to correct a damaged joint. Ultimately, your dentist will stabilize your bite so that the teeth, muscles and joints all work together without strain.

Once a thorough diagnosis has been made, the dentist will begin a personalized treatment program. Patients benefit from the non-surgical, conservative treatment our office provides. Individualized therapy will include muscle spasm reduction treatments in conjunction with an easy to wear, comfortable dental orthotic, referred to as a splint. The orthotic covers the lower teeth holding the jaw in proper alignment, reducing tension in the muscles of the jaw joint, allowing healing to take place. Once pain is controlled and the jaw joint is stabilized, the bite is balanced so the teeth, muscles and joints all work together in harmony.

It is important to assess the posture of each patient to determine whether or not the shoulders, pelvis and hips are level. Photos are taken of each patient to check for the above as well as to check for forward head posture. If there is a problem with the shoulders, hips or pelvis or if one leg is longer than the other, then a referral to a chiropractor would be necessary.

To solve the problem of forward head posture which can cause cervical (neck) problems, referral to a dentist or orthodontist who uses functional jaw orthopedic appliances should be made. These appliances such as the Twin Block, MARA or Herbst Appliance successfully reposition the lower jaw forward and eliminate the forward head posture.

For most patients, treatment is divided into two stages:

• Phase I Diagnostic Phase - Temporary Solution
  • Diagnostic Splints

• Phase II Treatment Phase - Permanent Solution
  • Orthodontics
  • Crown & Bridge
  • Prosthetics
  • Full Dentures
  • Partial Dentures
  • Composite buildups posterior teeth

Phase I Diagnostic Phase (Temporary Solution)

Diagnostic Splints

If there is an improper relationship between the upper and lower jaws and/or the upper and lower teeth, the patient will be required to wear temporary oral appliances (orthotic or splint). This TMJ splint is usually worn over the lower teeth until the bite and position of the lower jaw is stabilized. The objective of the lower splint is to try and establish the correct position of the mandible to the maxilla in three dimensions; namely, transverse, sagittal and vertical. The goal is to try and find a comfortable position for the lower jaw so that the patient can get some relief from the pain and muscle spasms. If the patient has a denture or a partial denture, the splint may be constructed over them similar to the method with natural teeth.

Lower Day Splint	Upper Night Appliance

Homecare of Splint

Since most head, neck and shoulder pain originates from muscle instability or swelling and inflammation of the joints, we may employ various physical modalities to treat and help normalize these structures. This includes such things as transcutaneous electrical nerve stimulation (TENS), moist heat therapy, vapor coolant sprays, and infrared treatments. These joints often get very tight in people with dysfunctions and various types of mobilization or stretching techniques are employed to gain normal function of these tissues.

TMJ

The temporomandibular joint (TMJ) is the joint connecting the lower jaw (mandible) to the skull (temporal bone). The lower jaw and the skull are connected by a number of muscles and ligaments, which function in harmony with each other if the lower jaw is in the correct position. The head of the jaw bone (lower jaw) is called the condyle and it fits into the concavity of the temporal bone called the glenoid fossa. The TM joint resembles a ball and socket with the round condyle being the ball and the glenoid fossa of the temporal bone being the socket. For normal joint function to occur, a piece of cartilage called an articular disc acts as a cushion or shock absorber between the two bones.

Normal Jaw Joint

When the lower jaw opens and closes, the disc stays between the condyle and the glenoid fossa of the temporal bone at all times. When this happens, this is a normal healthy TMJ and the patient can open wide without any discomfort and without any noise. With a normal opening, the patient should be able to get three fingers between the upper and lower front teeth when the mouth is open as wide as possible. In cases where the TM joint is functioning normally with the disc in the proper position, the muscles of the head, neck and shoulders function relatively pain-free.

What is TMD?

Temporomandibular disorder (TMD) is the condition referring to a joint that is not normal.

The position of your teeth can affect the position of your jaw joints. Each jaw joint is a ball and socket joint. When functioning properly, the ball and socket do not actually touch because a thin disc of cartilage rides between them. The disc acts as a cushion and allows the joint to move smoothly. Each disc is held in place and guided by muscles and ligaments. If your bite is not right, as in cases where the following may occur: deep overbite, lower jaw too far back, narrow upper jaw or upper front teeth crooked and tipped backwards, this can cause the jaw to become dislocated. Typically the disc is pulled forward. The lower jaw then has a tendency to go back too far and the top of the lower jaw, which resembles a ball (condyle), presses on the nerves and blood vessels at the back of the socket and causes pain.

Usually, the protective disc (cartilage) is displaced forward and no longer serves as a cushion between the condyle (lower jaw) and the bony socket (skull) and eventually this can lead to the condyle rubbing against the bony socket. This can cause a problem called osteoarthritis.

Mild displacements cause a clicking or popping sounds in the jaw joint.

When the disc becomes displaced, this is what causes the various noises within the jaw joints such as clicking and popping sounds. Patients must be aware that any noises or pain that occur during the opening and closing of the jaw is an indication that the jaw joints have become dislocated. Patients are advised to seek treatment as soon as possible to avoid allowing the problem to get worse.

More severe displacement can be very painful and eventually can cause permanent damage to the joint. An unstable bite can cause both jaw joint displacement and muscle strain and pain. Many seemingly unrelated symptoms results, which are collectively known as craniomandibular dysfunction. These symptoms include headaches, neck aches, ringing in the ears, stuffiness in the ears, pain behind the eyes, ear pain, shoulder and lower back pain, dizziness and fainting, difficulty swallowing, and tingling of the fingers and hands. These symptoms include:

• Headaches
• Neck aches
• Ringing in the ears
• Stuffiness in the ears
• Pain behind the eyes
• Ear pain
• Shoulder and lower back pain
• Dizziness and fainting
• Difficulty swallowing
• Tingling of the fingers and hands