What are TMJ disorders. How do they affect the jaw and overall health. What causes TMJ disorders. Who is most at risk for developing TMJ problems. How are TMJ disorders diagnosed and treated. What lifestyle changes can help manage TMJ symptoms. When should you see a doctor about jaw pain or discomfort.

What is the Temporomandibular Joint (TMJ)?

The temporomandibular joint, commonly referred to as TMJ, is a complex and crucial part of human anatomy. Located on both sides of the head, these joints connect the lower jaw (mandible) to the temporal bones of the skull. Their unique structure allows for a wide range of movements essential for everyday activities such as eating, speaking, and even breathing.

The TMJ is often overlooked when considering the body’s joints, yet it plays a vital role in our daily lives. Unlike other joints in the body, the TMJs work together as a unit, allowing for synchronized three-dimensional movements. This complexity makes the TMJ one of the most intricate joints in the human body.

Anatomy of the TMJ

The TMJ consists of several key components:

• Condyles: The rounded upper ends of the mandible
• Joint socket: Located at the base of the skull
• Articular disc: A soft tissue cushion between the condyle and socket
• Muscles: Attached to the mandible, controlling jaw movements

When you open your mouth, the condyles glide along the joint socket, returning to their original position when you close your mouth. The articular disc acts as a shock absorber, protecting the joint during various movements.

Understanding Temporomandibular Disorders (TMD)

Temporomandibular disorders, also known as TMD or TMJ disorders, encompass a range of conditions affecting the jaw joint and surrounding tissues. These disorders can cause significant pain and discomfort, often limiting jaw movements and impacting a person’s quality of life.

Recent research has revealed that TMJ disorders are more complex than previously thought. They are now recognized as multisystem conditions, affecting not only the jaw but also potentially involving the circulatory, digestive, endocrine, immune, muscular, nervous, reproductive, respiratory, and skeletal systems.

Comorbidities Associated with TMJ Disorders

Studies have shown that approximately 85% of patients with TMJ disorders also suffer from other conditions. These comorbidities include:

• Chronic fatigue syndrome
• Fibromyalgia
• Irritable bowel syndrome
• Chronic headaches
• Sleep disorders
• Neck and lower back pain
• Endometriosis
• Interstitial cystitis
• Vulvodynia

Additionally, certain autoimmune diseases and connective tissue disorders can affect the TMJ, including rheumatoid arthritis, Sjögren’s syndrome, and systemic lupus erythematosus.

Who is at Risk for Developing TMJ Disorders?

While TMJ disorders can affect anyone, certain groups are at higher risk. Understanding these risk factors can help in early detection and management of the condition.

Prevalence and Demographics

Estimating the exact prevalence of TMJ disorders in the United States is challenging due to data collection difficulties. However, current estimates suggest that between 10 to 35 million Americans are affected by TMJ disorders at any given time.

Interestingly, there is a significant gender disparity in the occurrence of severe TMJ symptoms:

• Women are more likely to experience severe symptoms than men
• The majority of severe cases occur in women of childbearing age
• The ratio of women to men increases with symptom severity, reaching up to 9:1 in cases with chronic pain and major jaw movement limitations

What Causes TMJ Disorders?

The etiology of TMJ disorders is multifaceted, with various factors contributing to their development. In some cases, the exact cause remains unknown, adding to the complexity of diagnosis and treatment.

Common Causes of TMJ Disorders

Some known causes of TMJ disorders include:

1. Autoimmune diseases: Conditions where the body’s immune system attacks healthy tissues
2. Infections: Bacterial or viral infections affecting the jaw area
3. Injuries: Trauma to the jaw or surrounding areas
4. Dental procedures: Prolonged mouth opening during dental work can strain the TMJ
5. Arthritis: Various forms of arthritis can affect the TMJ
6. Bruxism: Habitual teeth grinding or clenching
7. Stress: Emotional stress can lead to muscle tension in the jaw area
8. Hormonal changes: Fluctuations in hormone levels may contribute to TMJ disorders

Recognizing Symptoms of TMJ Disorders

TMJ disorders can manifest in various ways, affecting not only the jaw but also surrounding areas. Recognizing these symptoms is crucial for early diagnosis and treatment.

Common Symptoms of TMJ Disorders

Individuals with TMJ disorders may experience one or more of the following symptoms:

• Pain or tenderness in the jaw joint area
• Difficulty or pain when chewing
• Clicking, popping, or grating sounds when opening or closing the mouth
• Locking of the jaw joint, making it difficult to open or close the mouth
• Facial pain or ache
• Headaches, particularly in the temple area
• Earaches or ringing in the ears (tinnitus)
• Neck and shoulder pain
• Dizziness or balance problems
• Changes in the way the upper and lower teeth fit together

Is jaw pain always indicative of a TMJ disorder? Not necessarily. While jaw pain is a common symptom of TMJ disorders, it can also be caused by other conditions such as sinus problems, tooth infections, or even heart issues. It’s essential to consult a healthcare professional for an accurate diagnosis.

Diagnosing TMJ Disorders

Diagnosing TMJ disorders can be challenging due to the complexity of the condition and its overlapping symptoms with other health issues. Healthcare professionals typically use a combination of methods to reach a diagnosis.

Diagnostic Approaches for TMJ Disorders

The diagnostic process for TMJ disorders may include:

1. Medical history review: The healthcare provider will ask about symptoms, past injuries, and overall health
2. Physical examination: Checking jaw movement, listening for sounds, and assessing pain points
3. Imaging tests: X-rays, CT scans, or MRI may be used to visualize the jaw joint and surrounding structures
4. Bite analysis: Evaluating how the upper and lower teeth come together
5. TMJ arthroscopy: A minimally invasive procedure to directly view the joint

How long does it take to diagnose a TMJ disorder? The time to reach a diagnosis can vary depending on the complexity of the case. Some patients may receive a diagnosis after their initial consultation, while others might require multiple visits and tests over several weeks or months.

Treatment Options for TMJ Disorders

Treatment for TMJ disorders often involves a multidisciplinary approach, tailored to the individual’s specific symptoms and underlying causes. The goal is to alleviate pain, improve jaw function, and enhance overall quality of life.

Conservative Treatment Approaches

Initial treatment typically focuses on conservative, non-invasive methods:

• Physical therapy: Exercises to strengthen jaw muscles and improve mobility
• Medications: Pain relievers, anti-inflammatories, or muscle relaxants
• Oral appliances: Custom-fitted mouthguards or splints to reduce teeth grinding
• Stress management techniques: Relaxation exercises, mindfulness, or counseling
• Lifestyle modifications: Avoiding hard foods, limiting jaw movements
• Hot or cold therapy: Applying heat or ice packs to the affected area

Advanced Treatment Options

If conservative treatments don’t provide relief, more advanced options may be considered:

1. Botox injections: To relax overactive jaw muscles
2. Corticosteroid injections: To reduce inflammation in the joint
3. Arthrocentesis: A minimally invasive procedure to flush out the joint
4. Arthroscopy: A surgical procedure to repair or reposition the joint disc
5. Open joint surgery: Reserved for severe cases that don’t respond to other treatments

What is the success rate of TMJ disorder treatments? The success rate varies depending on the individual case and treatment approach. Many patients find relief with conservative methods, while others may require more advanced interventions. Long-term success often depends on a combination of professional treatment and self-care strategies.

Living with TMJ Disorders: Self-Care and Management

While professional treatment is crucial, self-care plays a significant role in managing TMJ disorders. Implementing certain lifestyle changes and home remedies can help alleviate symptoms and improve overall jaw health.

Effective Self-Care Strategies for TMJ Disorders

Consider incorporating these self-care techniques into your daily routine:

• Practice good posture: Maintain proper alignment of your head, neck, and spine
• Avoid overusing jaw muscles: Limit activities that strain the jaw, such as gum chewing or nail biting
• Use relaxation techniques: Practice deep breathing or meditation to reduce stress-related jaw tension
• Apply moist heat or ice packs: Use for 10-15 minutes at a time to relieve pain and stiffness
• Perform gentle jaw exercises: Follow your healthcare provider’s recommendations for stretching and strengthening exercises
• Maintain a soft diet: Choose foods that don’t require excessive chewing
• Practice good sleep hygiene: Ensure proper support for your head and neck while sleeping
• Be mindful of jaw clenching: Use reminders to relax your jaw throughout the day

Can lifestyle changes alone cure TMJ disorders? While lifestyle modifications can significantly improve symptoms for many individuals, they may not be sufficient to completely cure TMJ disorders in all cases. It’s essential to work with healthcare professionals to develop a comprehensive treatment plan that combines professional care with self-management strategies.

When to Seek Medical Help for TMJ Symptoms

While some TMJ symptoms may resolve on their own, certain signs indicate the need for professional medical attention. Knowing when to seek help can prevent the condition from worsening and ensure timely treatment.

Signs That Warrant Medical Attention

Consider consulting a healthcare provider if you experience:

1. Persistent jaw pain or tenderness
2. Inability to open or close your mouth fully
3. Jaw locking in an open or closed position
4. Significant changes in your bite alignment
5. Severe headaches or migraines associated with jaw pain
6. Difficulty eating or speaking due to jaw discomfort
7. Noticeable facial asymmetry or changes in facial appearance
8. Symptoms that significantly impact your quality of life

How urgent is it to see a doctor for TMJ symptoms? While TMJ disorders are rarely life-threatening, severe or persistent symptoms should be evaluated promptly. Early intervention can prevent the condition from progressing and improve treatment outcomes. If you experience sudden, severe pain or inability to open or close your jaw, seek immediate medical attention as these could indicate a more serious condition.

Future Directions in TMJ Disorder Research and Treatment

As our understanding of TMJ disorders continues to evolve, researchers are exploring new avenues for diagnosis, treatment, and prevention. These advancements hold promise for improved patient outcomes and quality of life.

Emerging Research and Potential Breakthroughs

Some areas of ongoing research in TMJ disorders include:

• Genetic factors: Identifying genetic markers associated with TMJ disorders
• Biomarkers: Developing blood tests or imaging techniques for early detection
• Regenerative medicine: Exploring stem cell therapies to repair damaged joint tissues
• Personalized medicine: Tailoring treatments based on individual genetic and environmental factors
• Advanced imaging techniques: Improving diagnostic accuracy and treatment planning
• Novel drug therapies: Developing targeted medications with fewer side effects
• Minimally invasive surgical techniques: Refining procedures for better outcomes and faster recovery

What potential breakthroughs are on the horizon for TMJ disorder treatment? While it’s difficult to predict specific breakthroughs, ongoing research in areas such as regenerative medicine and personalized treatments shows promise. These approaches could lead to more effective, less invasive treatments that address the root causes of TMJ disorders rather than just managing symptoms.

As research progresses, it’s likely that our understanding of TMJ disorders will continue to expand, leading to more targeted and effective treatments. Patients and healthcare providers alike can look forward to a future where TMJ disorders are better understood, more easily diagnosed, and more effectively managed.

TMJ Basics – The TMJ Association

What is the Temporomandibular Joint?

“Consider the joints of the human body. What might first come to mind are the hips and knees—the large joints that support us in our mobility—followed by the wrists, ankles, elbows, fingers, and toes. What can be overlooked, although clearly evident in the mirror, is one of the most used, most necessary, and perhaps most misunderstood set of joints—those of the jaw—which are critical to the vital work of human life, including eating, talking, kissing, and even breathing.” (2020 National Academy of Medicine Report on TMJ)

TMJ stands for Temporomandibular Joint, or jaw joint. The TMJs are the two joints in front of each ear. The joints connect the lower jaw bone (the mandible) to the temporal bones of the skull on each side of the head. The muscles controlling the joints are attached to the mandible and allow the jaw to move in three directions: up and down, side to side, and forward and back. When intact, they are the only joints in the human body that work together as a unit.

Anatomy of primary masticatory muscles and the temporomandibular joint. Souce: Mayo Clinic 2019

When you open your mouth, the rounded upper ends of the mandible on each side of the jaw (the condyles) glide along the joint socket at the base of the skull. They slide back to their original position when you close your mouth. To keep this motion working smoothly, a soft tissue disc lies between the condyle and the socket. The disc absorbs the shock to the joint from chewing and other movements.

The combination of synchronized, as well as three-dimensional movements of the TMJ, distinguishes the TMJ as the most complicated joint in the body. The TMJ also differs in biological composition from other weight-bearing joints, like the hip or knee.

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What are Temporomandibular Disorders?

Temporomandibular disorders, also commonly referred to as TMJ or TMD, are a complex, under-researched, and poorly understood set of conditions characterized by pain in the jaw joint and surrounding tissues frequently associated with limitation in jaw movements. Recent finds show that TMJ is a complex multisystems condition involving the circulatory, digestive, endocrine, exocrine, immune, muscular, nervous, reproductive, respiratory, and the skeletal system. TMJ is no longer seen as a condition confined solely to the areas of the jaws and teeth.

Scientists have found that 85% of patients with TMJ also suffer from other conditions – pain and non-pain conditions in other parts of the body. These conditions include allergies, chronic fatigue syndrome, chronic headache, endometriosis, fibromyalgia, interstitial cystitis, irritable bowel syndrome, neck and low back pain, sleep disorders, and vulvodynia.

In addition, connective tissue disorders and autoimmune diseases that can affect the TMJs include: rheumatoid arthritis, juvenile rheumatoid arthritis, juvenile idiopathic condylar resorption, psoriatic arthritis, ankylosing spondylitis, Sjogren’s syndrome, systemic lupus erythema, scleroderma, mixed connective tissue disease, etc.  As a result, multiple systems are usually involved.  

These other conditions are considered to be comorbid with TMJ because they occur together more often than by chance. In addition, the conditions share other features. These findings are stimulating research into common mechanisms underlying all of these comorbid conditions. Note that many of the comorbidities mentioned are more prevalent or occur exclusively in women.

The left, right or both components of the temporomandibular joint may be involved and, depending on the severity, can affect a person’s ability to speak, chew, swallow, make facial expressions, and even breathe. Jaw muscle disorders are also included as these may accompany jaw joint problems or occur independently.

Who is Affected?

The national prevalence of Temporomandibular Disorders is difficult to estimate due to challenges in collecting data, however estimates range from 10 to over 35 million people in the United States are affected by TMJ at any given time. Clearly, research to understand the prevalence of this condition desperately is needed.

While both men and women experience these disorders, the majority experiencing the most severe symptoms are women in their childbearing years. The ratio of women to men increases with the severity of symptoms, approaching nine women for every one man with major limitations in jaw movements and chronic, unrelenting pain.

What Causes TMJ Disorders?

Adding to the complexity of TMJ disorders is that there are multiple causes, including cases where no obvious cause can be found. Some known causes are the following:

• autoimmune diseases (in which the body’s immune cells attack healthy tissue)
• infections
• injuries to the jaw area
• dental procedures (even prolonged mouth opening)
• insertion of a breathing tube before surgery
• various forms of arthritis

Additionally, there are genetic, hormonal, and environmental factors that can increase the risk for TMJ. Studies have shown that genetic factors contribute to TMJ and are leading to the discovery of new ways of treating TMJ.

The observation that jaw problems are commonly found in women in the childbearing years has also led to research to determine the role of female sex hormones, particularly estrogen, in TMJ.

Symptoms

Symptoms can range from sounds in the joint to severe, debilitating pain and dysfunction. However, some people report no pain but still have problems moving their jaws. Symptoms may include the following:

• pain in the jaw muscles
• pain in the neck and shoulders
• chronic headaches
• jaw muscle stiffness
• limited movement or locking of the jaw
• ear pain, pressure, fullness, ringing in the ears (tinnitus)
• grating in the jaw joint when opening or closing the mouth
• a bite that feels “off”
• dizziness
• vision problems

Keep in mind that occasional clicking or discomfort in the jaw joint or chewing muscles is common and is not always a cause for concern. Often, the problem goes away on its own in several weeks to months.

Diagnosis

The patient’s medical history should not be restricted to the dentition (the teeth and their arrangement) or to the head and neck, but instead a far more comprehensive medical assessment of the patient is needed, which may reveal one or more of the comorbid conditions found to occur frequently in TMJ patients.

The OPPERA study found TMJ disorders are a widespread pain manifested outside the orofacial region with the presence of multiple comorbid persistent disorders in many patients. The most influential predictors of clinical TMJ are simple 20-checklists of comorbid health conditions and nonpainful orofacial symptoms.

Blood tests are sometimes recommended to rule out possible medical conditions as a cause of the problem which may mimic TMJ symptoms. Read more about this topic.

Comorbidities

Scientists have found that 85% of patients with TMJ disorder also suffer from both chronic pain and non-pain conditions in other parts of the body. These conditions are called “comorbid” because they occur together more often than chance can explain. In addition, the conditions share other features, such as similar risk factors, symptoms and underlying disease mechanisms.

These findings are stimulating research into common mechanisms underlying all of these comorbid conditions. Indeed, research indicates that TMJ disorders are a set of complex diseases like hypertension or diabetes involving genetic, environmental, behavioral, and sex-related factors.

Studies have shown that the following 30 health conditions can coexist with TMJ disorders.

• Ankylosing spondylitis in other body joints
• Asthma
• Back, neck, and joint pain
• Chronic fatigue syndrome
• Ehlers-Danlos syndrome
• Endometriosis
• Fibromyalgia
• Irritable bowel syndrome
• Headaches
• Heart disease
• Hypertension
• Interstitial cystitis/painful bladder syndrome
• Juvenile idiopathic arthritis in other body joints
• Neural/sensory conditions
• Osteoarthritis in other body joints
• Poor nutrition due to alerted jaw function and/or pain while chewing
• Psoriatic arthritis in other body joints
• Respiratory conditions (e. g., sinus trouble, allergies or hives, asthma, tuberculosis, breathing difficulties)
• Rheumatoid arthritis in other body joints
• Sinusitis
• Sjogren’s syndrome
• Sleep disorders (e.g., insomnia, poor sleep quality, longer sleep latency, lower sleep efficiency)
• Somatic and psychological symptoms (e.g., depression, anxiety and post-traumatic stress disorder)
• Systemic lupus erythematosus
• Tinnitus
• Vertigo
• Vulvodynia

Not everyone who develops one of these conditions will go on to develop more, however many people with TMJ disorders do, particularly women. Read more about this topic.

Treatments

Most people with TMJ problems have relatively mild or periodic symptoms which may improve on their own within weeks or months with simple home therapy. Self-care practices, such as eating soft foods, applying ice or moist heat, and avoiding extreme jaw movements (such as wide yawning, loud singing, and gum chewing) are helpful in easing symptoms.

According to the National Institutes of Health brochure on TMJ, it strongly recommends using the most conservative, reversible treatments possible. Conservative treatments do not invade the tissues of the face, jaw, or joint, or involve surgery. Reversible treatments do not cause permanent changes in the structure or position of the jaw or teeth. If TMJ issues become persistent and severe, moving toward aggressive treatments does not necessarily ensure improvement of the symptoms.

Clearly, more research is needed that will lead to the understanding of the condition and development of safe and effective TMJ treatments. As science learns more about the TMJ and its associated structures, many in the health care community are reassessing TMJ treatments and ways in which they were developed. Clearly, the various TMJ disorders are far more complex than previously believed. Read more about this topic.

Insurance Coverage

There are no standardized costs for TMJ treatments. Costs can vary from provider to provider and from state to state. Treatment costs can range from several hundred dollars up to hundreds of thousands of dollars. 

Many medical and dental insurance plans do not cover TMJ treatments or only pay for some procedures. Until there are scientifically validated, safe and effective treatments, insurance companies will not pay for treatments that have questionable outcomes. In some situations, your insurance company will not cover costs because TMJ is classified by many insurance companies as a dental and not a medical condition. Contact your insurance company to see if they will cover the cost of a treatment being recommended to you. Read more about this topic.

Who Treats TMJ Disorders?

Since 1936 TMJ has been primarily treated by dentists, however today, we know TMJ to be a complex condition with many biological systems (circulatory, digestive, endocrine, exocrine, immune, muscular, nervous, reproductive, respiratory, and skeletal) playing a role, indicating the need to bring the medical and other allied health professionals in research and patient care.

It’s important to first rule out other conditions that may mimic TMJ symptoms by consulting your medical doctor. For example facial pain can be a symptom or a result of conditions, such as:

• sinus or ear infections
• decayed or abscessed teeth
• various types of headache
• facial neuralgia (nerve-related facial pain)
• tumors
• connective tissue disorders such as Ehlers Danlos Syndrome
• Eagles syndrome
• Dystonia
• Lyme Disease
• Scleroderma

There are no formally developed standards of care for TMJ in clinical dentistry or medicine. Although a variety of health care providers advertise themselves as “TMJ specialists,” most of the more than 50 different treatments available today are not based on scientific evidence of safety and efficacy. These doctors practice according to one of many different schools of thought on how to best treat TMJ. 

The National Institutes of Health (NIH) advises patients to look for a health care provider who understands musculoskeletal disorders (affecting muscle, bone and joints) and who is trained in treating pain conditions. Pain clinics in hospitals and universities are often a good source of advice, particularly when pain becomes chronic and interferes with daily life.

Complex cases, often marked by chronic and severe pain, jaw dysfunction, comorbid conditions, and diminished quality of life, will likely require a team of doctors from fields such as neurology, rheumatology, pain management, and other specialties for diagnosis and treatment.

Stigma

The lack of credible information relayed to the public and professionals about the reality of impact that TMJ can have on one’s overall health and life results in patients continuing to suffer in silence and isolation because nobody – including family, friends, employers, etc. – can comprehend how multiple therapies, including years of treatments at exorbitant costs cannot fix or alleviate the problem but seem to worsen it. It is always the fault of the patient when things don’t work out like they were told it would, leaving the patient to question what they did wrong.     

Advertisements portray TMJ as a simple click and pop that can easily be fixed. TMJ is often trivialized by the dental and medical communities as an insignificant problem.

Adding to the stigma for many TMJ patients, are the physical changes to their face as a result of surgical “readjustments”, paralysis, etc. Many patients express despair that they don’t recognize themselves anymore. Patients have also told us that they are embarrassed to be seen or to eat in public, because chewing and swallowing are difficult, they choke, and/or food falls out of their mouths. Speaking and enunciating words properly is often difficult and also embarrassing. Facial paralysis and the inability to smile is often times misinterpreted as a foul personality. Read more about this topic.

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Surgery For TMJ | Everything You Need To Know [Guide]

Temporomandibular joint and muscle disorders, commonly called TMJ disorders, are a group of conditions that cause pain and dysfunction in the jaw joint and in the muscles that control jaw movement. There are several treatment options available, depending on the cause and severity of ffeefqqthe disorder. We look at the symptoms, causes, and what’s involved in corrective jaw surgery or TMJ surgery, if required.

What are the TMJs?

The temporo-mandibular joints (TMJs) attach the lower jaw (mandible) to the base of the skull. There are two joints (one on each side of the face), located in front of the ears and ear canals. 

The TMJs are unique in that they are “bimodal,” which means they allow both hinge rotation and translation sliding. They are also via a single bone—the lower jaw. The TMJs are controlled by numerous facial muscles that help control lower jaw movement, and guide the dental bite.

What is a TMJ disorder?

A TMJ disorder can produce pain, as well as reduce the movement of your jaw (limited mouth opening). Individuals may experience pain in different parts of the face, including in the jaw joints themselves, and in the muscles that control jaw movement (temples of the skull / ears / upper neck region / cheek bones). Pain is also most commonly one-sided (although it can be on both sides of the face). It is typically associated with reduced movement of the lower jaw and affects the ability of a patient to open their mouth (hence causing problems with eating and speech). 

Symptoms of TMJ disorder include:

• Persistent pain around the ears that is made worse with jaw movement
• Difficulty chewing a normal consistency diet
• Jaw stiffness with lack of mobility (reduced and/or painful mouth opening)
• Clicking or locking (open or closed) of the jaw
• The inability to completely use the jaw’s full range of movement, especially when yawning or laughing

What causes TMJ disorders?

The exact cause of a person’s TMJ disorder is often difficult to determine. Some people who have jaw pain also tend to clench, grind or gnash their teeth — a condition known as bruxism. Bruxism may not be evident (subconscious clenching of your teeth during sleep) or you may be aware (conscious bruxism) that you grind or clench your teeth during the day. Mild bruxism may not require treatment, however, if severe enough, it may lead to headaches, damaged teeth, and jaw disorders.

The temporomandibular joint combines a hinge action with sliding motions. The joint surfaces are covered with cartilage and separated by a small shock-absorbing cartilage disc, which normally keeps the movement smooth. Sometimes the cartilage disc moves out of position and leads to TMJ dysfunction.

TMJ disorders can also be due to: 

• Either damage to or displacement of the disc
• Connective tissue disorders that affect the temporomandibular joint
• The joint’s cartilage lining being damaged by arthritis, including osteoarthritis, rheumatoid arthritis or inflammatory arthritis
• The joint being damaged by injury such as a blow or other impact
• Malformation of the TMJ anatomy from birth (Genetic predisposition) 

What are the treatment options for TMJ disorders?

In 95% of cases, the pain and discomfort associated with TMJ disorders is temporary and can be relieved with self-managed care or non-surgical treatments. These include medication, physical therapy, or lifestyle changes. 

Surgery is typically a last resort after other measures have failed, although some people with TMJ disorders may benefit from surgical treatments. Non-invasive therapies include:  

• Joint rest—reducing jaw movements to within the range of mouth opening that is comfortable, and keeps your upper and lower jaw teeth apart when at rest.
• A soft-food diet—eating a pureed or softened diet that doesn’t exacerbate the pain.
• Medications to relieve jaw pain and/or relax muscles—including muscle relaxants, non-steroidal anti-inflammatory medications, or certain medications used to treat depression.
• Heat or cold packs—that relieve pain when applied directly to the site.
• TMJ physiotherapy—including acupuncture, relaxation exercises, posture improvement, neck treatment, TMJ joint mobilisation, TMJ movement pattern, timing correction, and TMJ stabilisation exercises.
• Wearing an occlusal splint or mouth guard—which can minimise jaw clenching or teeth grinding, especially at night.

What exercises can I do to improve my jaw function?

There are a range of exercises you can do yourself that may reduce jaw “clicking” and strengthen the muscles that pull your jaw backwards. They can also help relax the muscles that close your mouth and prevent the functioning of the muscles that pull the jaw forwards from side to side. This will reduce strain and allow your jaw to act more like a hinge. One of these involves:

• Setting aside two five-minute periods every day at a time when you are relaxed, for example, just before you go to bed or get up in the morning.
• Start by sitting upright in a chair.
• Close your mouth and make sure your teeth are touching but not “clenching”. Rest the tip of your tongue on your palate, just behind your upper front teeth.
• Keep your teeth together and run the tip of your tongue backwards towards your soft palate, as far as it will go.
• Force your tongue back to maintain contact with the soft palate and slowly open your mouth, but only until you feel your tongue being pulled away.
• Stay in this position for five seconds, then close your mouth and relax.
• Repeat the whole procedure slowly but firmly for the next five minutes.
• As you open your mouth, you should now feel tension in the back of your neck and under your chin.
• The first few times you perform the exercise, check in a mirror that your teeth move vertically downwards and do not deviate to either side.
• If you are performing the exercises correctly, there will be no noises like “clicks” from the joints. If there is, restart the exercise and continue practising until you don’t hear any clicking.
• It is recommended you don’t do these exercises for more than five minutes, twice a day for the first week.
• After that, do the exercises as often as you can. This will relax the muscles that close your mouth and help strengthen the ligaments around your jaw.
• You might find that TMJ dysfunction pain is worse for a while at first — this is because your body is unaccustomed to the movement. Over time this should subside.
• After two to three weeks, you should find that your muscles have been “re-trained,” and your jaw will open and close smoothly without clicking.
• If not, you should make an appointment with your Oral and Maxillofacial Surgeon for further advice.

Do I need jaw surgery for TMJ disorders?

Surgery is performed by an Oral and Maxillofacial Surgeon, preferably one with surgical experience and skills in TMJ surgery. Dr Tite, who works at our Gold Coast clinic, introduced TMJ surgery to the area almost 20 years ago and remains one of the most experienced providers of TMJ procedures to date.

TMJ surgery, including TMJ reconstruction surgery, may be recommended to correct your TMJ disorder if you experience:

• TMJ locking—the inability to fully open or close your mouth.
• Continuous facial pain and/or TMJ dysfunction—despite having trialled non-surgical therapies for at least six months.
• Intense pain—that is unable to be eased using analgesic medications.
• An inability or extreme difficulty eating or drinking—because of jaw pain or immobility.
• TMJ destruction via trauma—such as facial injuries after a car or motorbike accident.
• TMJ destruction via disease—such as rheumatoid and osteoarthritis or tumours involving the TMJ.
• Facial deformities that affect the development of the TMJs—including Hemi-facial microsomia, Goldenhar syndrome, and TMJ ankylosis.

When is surgery not recommended?

Your Specialist Oral and Maxillofacial Surgeon may advise against jaw surgery to fix TMJ if:

• Your TMJ symptoms respond to non-surgical therapies.
• Your symptoms are inconsistent, with painful symptoms one day and no pain the next (this may be simply a case of fatigue in your TMJ).
• You have a full (unrestricted) range of mouth opening.
• You aren’t medically fit enough to undergo a general anaesthetic for the surgery.

Types of jaw surgery for TMJ

The commonly performed procedures for treatment of TMJ disorders are:

• Arthroscopic jaw surgery
• Arthroplasty (Total joint replacement) jaw surgery

Arthroscopic jaw surgery

An arthroscopy is the most common and least invasive jaw surgery for TMJ. It is a same-day surgical procedure performed under general anaesthesia. During surgery, the Specialist Surgeon will make two small incisions in the skin in front of the ear overlying the TMJ. A narrow port (called a cannula) is inserted through the skin and directed into the joint. The joint can then be directly inspected (via an arthroscope or small camera), manipulated and instilled with medications (pain relief and steroids).

This detailed examination helps the surgeon understand the causes of TMJ pain and dysfunction, remove inflamed tissue, and encourage tissue healing which is typically assisted by TMJ medications. Recovery time is generally short (several days) as the pain and swelling subsides.

Arthroplasty (Total Joint Replacement) jaw surgery

Arthroplasty is a moderately invasive surgery for TMJ. This procedure replaces both the ball (mandibular condyle head and cartilage disc) and socket (glenoid fossa) of the TMJ with a new custom-made artificial TMJ constructed from titanium and high-density plastic. The surgery begins with an incision (above and below the ear) to expose and remove the defective TMJ. The artificial TMJ is then inserted.

During the surgery, the surgeon may remove bony growths, excess tissue or some of the diseased bone. This TMJ replacement allows the patient to regain comfortable, functional movement of the joint, including mouth opening. 

Stages of arthroplasty jaw surgery for TMJ

Stage 1 – Before jaw surgery

An initial comprehensive surgical assessment by your Specialist Oral and Maxillofacial Surgeon will confirm whether isolated TMJ replacement surgery is needed, or whether other adjunctive procedures (such as facial reconstructive surgery) are to be combined with the TMJ procedure.

To plan for your TMJ surgery, X-rays, three-dimensional CT scans and three-dimensional images of your teeth are taken. To achieve the most optimal result, the Specialist Surgeon will use computer-based virtual surgical planning techniques to create both a customised surgical plan and guides. This process improves the accuracy of the replacement TMJ appliance and reduces both operative time and surgical complications.

Stage 2 – Jaw surgery

After accessing the TMJ, the surgeon removes the diseased TMJ (using the surgical guides made in Stage 1), reshapes the bone, and then uses a secondary surgical guide to insert the TMJ replacement appliance. The new TMJ appliance is secured directly to the lower jaw with small titanium plates and screws.

Stage 3 – After jaw surgery

Following your surgery, your Specialist Oral and Maxillofacial Surgeon will provide you with guidelines to follow during your recovery from surgery. These include:

• Dietary guidelines—for the first few days, you will be restricted to a soft, semi-fluid and/or liquid-only diet.
• Oral hygiene guidelines—it is essential these are followed. They include keeping your mouth and teeth clean to support faster healing and decrease the risk of infection. After snacks, each meal and before bed, you should brush your teeth with a soft-bristled, child-size toothbrush. Use a circular motion and angle the brush at forty-five degrees toward the gum line. If brushing is impossible, wipe over your gums and tooth surfaces with a moistened cotton tip.
• Exercise guidelines—strenuous activity should be avoided. Your Oral and Maxillofacial Surgeon may also prescribe physical therapy and jaw exercises to help your jaw recover.
• Medication guidelines—your surgeon will advise you on medications to control pain and reduce inflammation.

It’s also worth mentioning that in contemporary practice, the wiring together of a patient’s jaws is virtually never needed. Occasionally, light elastic bands may be applied to your teeth to guide (but not lock together) your jaws and dental bite.

This surgery is reserved for severe cases of TMJ disorder where: 

• The joint or joint surfaces have degenerated from a traumatic injury or tumour involvement.
• The patient has severe osteoarthritis (age related joint dysfunction) or rheumatoid arthritis (auto-immune disease).
• Bone and tissue overgrowth prevents the joint from moving, including reduced mouth opening and ankylosis (the abnormal stiffening and immobility of a joint due to a fusion of the bones).

This is the most intensive surgery for TMJ and usually takes three to four hours to complete. The patient is under general anaesthetic and requires a three to five-day stay in hospital. In terms of recovery time, initial jaw healing typically takes around six weeks after surgery, but it will take more than a month before you can resume regular activity. Patients should plan a three to four week absence from work and complete healing can take up to twelve weeks.

Talk to the TMJ Specialists at Dental Implant and Specialist Centre to discuss surgical options for your TMJ, by contacting them on (07) 5503 1744.

References

• 2021, TMJ Disorders, Mayo Clinic
• 2021, Patient Information on Temporomandibular Joint (TMJ) Exercises, Melbourne ENT Group
• 2021, Bruxism (teeth grinding), Mayo Clinic

Pathology of the temporomandibular joint – symptoms and treatment in the Ilyinsky hospital.

Our task is to choose the type of therapeutic or
surgical treatment, which will allow a minimally traumatic way
restore the natural function of the temporomandibular joint and restore
patient a high quality of life.

• Our specialists

a diverse group of experts, each member of which has a deep theoretical
knowledge, filigree manual skills and extensive treatment experience
TMJ diseases. Our team has the best specialists who have achieved
maximum results in the treatment of the most complex and rare pathologies
TMJ. Oral and maxillofacial surgeons at the Ilyinsky Hospital work closely with
leading experts of the European Association for cranio-maxillo-facial surgeons EARMFS (European association for cranio-maxillo-facial surgeons), follow
current clinical guidelines and use only those methods of treatment, the effectiveness of which has been proven
international clinical trials.

• Emergency

go to a regular emergency room. We provide assistance around the clock
TMJ injuries and other emergencies. At the emergency department
Ilyinsky hospital has a 24-hour X-ray room and
computed tomography (CT). CT examination allows you to quickly
make an accurate diagnosis and choose the best treatment tactics, which is extremely important
in emergency situations. At any time of the day, a surgeon is on duty in the hospital with
Extensive experience in emergency surgery. If the injury
requires highly specialized care, for example, participation in a vascular operation
surgeon or neurosurgeon – such a specialist can arrive in the operating room at
within one hour. During this time, the surgeon on duty will revise the wound and
primary treatment, stop blood loss, prepare the patient for
specialized intervention. To know
more.

• Diagnosis

Gold standard for disease diagnosis
temporomandibular joint is a magnetic resonance imaging with
kinematics (MRI). The method does not carry a radiation load for the patient and represents
is a series of sequential pictures of the gradual opening of the patient’s mouth. MRI with
kinematics allows you to accurately determine the position by the dynamics of the opening of the mouth
head of the joint in relation to the articular surfaces and assess the position of the articular
disk. Based on the conclusion of this study and clinical examination
the final diagnosis is made and an individual plan is formed
treatment of this patient. Ilyinsky hospital is equipped with the most modern
magnetic resonance imaging. To learn more.

• Surgical treatment
  luxation of the articular disc

This pathology usually affects young people who
often do not understand the cause of their problem. They complain about clicks that
may be accompanied by impaired chewing function. Danger of dislocation
of the articular disc is that without timely treatment, the patient
idiopathic osteoresorption (destruction) of the joint head occurs, which
leads to a violation of the correct functioning of the lower jaw. Disk luxation treatment begins
with a consultation with an orthodontist. If indicated, surgical
treatment – surgery to reposition the disc and fix the head in an anatomically
correct position to avoid further resorption. This is an operation
open type, the surgeon performs a curly incision behind the earlobe – aesthetically
advantageous area. The operation does not disturb the appearance of the patient, does not
cosmetic discomfort. The surgeon then peels off an L-shaped skin flap, and
gains access to the joint. Washing out of inflammatory mediators (substances
that contribute to the maintenance of the inflammatory process). Performed if necessary
arthroplasty is the normalization of the anatomical shape of the head, which has been changed for
account of the pathological process, as well as fixation of the disk itself.

• Treatment of synovitis and
  TMJ arthritis

Synovitis of the temporomandibular joint is
inflammation of the synovial capsule of the joint, which is accompanied by the accumulation
fluid in its cavity, and a slight limitation of function. Also for arthritis
characterized by an inflammatory lesion of the joint, which, unlike synovitis,
significantly limits the function – the patient cannot fully open his mouth. Both
diseases respond well to conservative treatment with medications and physiotherapy
influences. In difficult cases, surgeons at the Ilyinsky hospital resort to
minimally invasive treatment through arthropuncture, that is, the introduction
drug into the joint cavity. Depending on individual
characteristics of the patient, it can be injections with the use of glucocorticoids
or a biopolymer gel that stimulates regeneration – restores
cartilage tissue of the joint. Also for the treatment of inflammatory diseases
TMJ arthrocentesis is used – this is lavage (drainage) of the upper articular
space with Ringer’s solution and a needle through which this solution
enters the joint and is excreted from it. Manipulation is carried out in outpatient clinics.
conditions under local anesthesia. The procedure allows you to stop the pain syndrome
and inflammation, washing away tissue breakdown products and mediators
inflammation (biologically active substances that support the inflammatory
process and are the cause of pain). It also allows the destruction of adhesions,
improve mobilization of the joint and articular disc.

• Treatment of arthrosis of the TMJ

Arthrosis is a degenerative-dystrophic
diseases that are characterized by gradual dystrophic changes
cartilage and bone tissue of the joint. The patient is worried about constant dull, aching
pain in the joint, the presence of a crunch and stiffness when opening the mouth. Main
therapeutic measures are aimed at restoring work
temporomandibular joint, and slowing down the progression of dystrophic
process. The task of the doctor is to transfer the disease to a state of stable remission.
This is possible through the use of modern drugs with
proven effectiveness, and conducting physiotherapy treatment in
combination with massage and special physiotherapy exercises.

• Arthroscopy

Arthroscopy belongs to the category of minor surgical
interventions, according to individual indications, it is used for diagnosis or
treatment of various TMJ pathologies. During the operation, the joint is not opened –
surgeons use a special navigation technique, all manipulations
carried out through punctures. Can be used for arthroscopy
local anesthesia, but more often the method of choice is intravenous sedation and endotracheal
anesthesia. The main criterion for choosing a method of anesthesia is comfortable
the patient’s well-being. Arthroscopy is less traumatic, favorably affects
long-term prognosis, recovery after the intervention is fast.

• Rehabilitation

modern methods of restoring functions after diseases and injuries of the TMJ. He
includes a special complex of exercise therapy, massage, various types of equipment
physiotherapy. For each patient, the rehabilitation specialists of the Ilyinsky hospital
a personalized program tailored to their needs and
individual characteristics. Rehabilitators of the Ilyinsky hospital in collaboration with
operating surgeon and general practitioners make the recovery process
as fast and efficient as possible. Rehabilitation can be carried out in conditions
inpatient and outpatient basis.

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Features of the structure and functioning of the temporomandibular joint in children

Pathology of the temporomandibular joint (TMJ) occupies a special place among dental diseases. The reason for this is the heterogeneity and polymorphism of the clinical picture, the progressive course, the variety of etiological factors and the presence of multiple, often mutually aggravating, pathogenetic links. Often, TMJ disorders are disguised as ENT pathologies, neuropathies, and psychosomatic diseases [1–4]. The debut of symptoms of TMJ diseases occurs at different ages (from newborn to the elderly), and there is also a different way out of the disease (persistent remission or progression and chronicity of the pathological process). A feature of TMJ diseases is also different tolerance to the same methods of treatment. Thus, the pathology of the TMJ is a special cluster of dental pathology, which, of course, affects the quality of life of the patient as a whole, and its dental component [5—8].

Diagnosis and treatment of TMJ pathology is impossible without a clear understanding of the anatomical structure of the joint. On the one hand, the TMJ as an anatomical complex is a stable unit of the human body as a whole, on the other hand, the elements of this complex undergo physiological changes throughout life [2, 7]. The TMJ refers to complex formations both in terms of anatomical structure and function. The structure of the joint is closely related to the functional state of the entire complex of organs of the masticatory apparatus.

The purpose of this work was to study the structure and function of the TMJ in children in terms of age.

Material and methods

To study the morphological changes in the tissues of the TMJ, we analyzed the case histories of 20 children with various pathologies of the antenatal period of development and diseases of early age, and also examined sectional material.

Morphological studies were carried out on the basis of the pathoanatomical department of the Regional Children’s Clinical Hospital (headed by Ph.D. E.S. Patlusova) of Perm. After opening, the organs were fixed in a 10% formalin solution for 24 h, followed by passage using a Leica TP 1020 histoprocessor for 18 h using alcohols of increasing strength and embedding in paraffin in a Histostar filling station from Thermoscientific. Sections with a thickness of 3 μm were made from ready-made paraffin blocks on a Microtom Hm 325 semi-automatic microtome with a given cut thickness. Staining was carried out with hematoxylin and eosin for a review technique and according to Van Gieson to assess the degree of scleroplastic changes.

Morphometric study of organs was used as an additional method. In this section, the thickness of the epithelial layer, the severity of perivascular edema, the thickness of the vascular walls and the width of the vascular lumens were assessed in order to assess the degree of emerging vascular disorders that can cause secondary changes in the organs of the oral cavity over time.

Morphometric study of preparations was performed using an Axioskop 40 (´4, ×10, ×40) binocular light microscope with a ×10 eyepiece and a computer image analysis system. It included: a light microscope, an Infinity 1 color video camera, an IBM compatible computer and software. Images (using the Infinity Analyze program) were digitized and transferred for subsequent storage to a computer hard drive. Computer analysis of images was carried out using the Infinity Analyze program.

Results and discussion

The TMJ of a newborn is characterized by the absence of the articular tubercle and a flat, rounded fossa, the articular head is covered with a thick layer of cartilage and has no slope (Fig. 1). The articular disc is a soft fibrous layer between the articular head and the future articular tubercle (Fig. 2). The articular disc, together with the articular cone, acts as a shock absorber, protecting the organs located in the border areas from injury. Protective value is also adipose tissue, located in the form of lobules on the anterior and posterior surfaces of the joint (Fig. 3). In infancy, the lower jaw occupies a distal position, in which the articular head is located in the posterior part of the articular cavity, i.e., the entire articular fossa functions.

Rice. 1. Temporomandibular joint. Cartilaginous elements in the articular head. Stained with hematoxylin and eosin, ×10.

Rice. 2. Fibrous elements in the area of ​​the articular disc. Stained with hematoxylin and eosin, ×4.

Rice. 3. Temporomandibular joint. Adipose tissue around the joint. Stained with hematoxylin and eosin, ×10.

After teething, the structure and shape of the TMJ elements change. In a child aged 1.5 years, who eats food of a denser consistency, the temporomandibular joint changes: the articular tubercle acquires a pronounced bulge, the articular fossa deepens, the articular disc acquires a biconcave shape, and the restructuring of the articular cone begins. In connection with the eruption of temporary molars and an increase in the height of the bite, there is a further movement of the articular head anteriorly.

The period of tooth change is characterized by intensive growth of the entire masticatory apparatus and differentiation of the elements of the TMJ. In connection with the second increase in the height of the occlusion, there is a further movement of the articular head anteriorly, as a result of which it is located in the center of the glenoid fossa. In this case, the articular disc acquires the final biconcave shape; its lower surface corresponds in shape to the articular head, and the upper surface to the articular tubercle. There is an anterior inclination of the articular head.

With the third physiological increase in the height of the occlusion, the translational movement of the articular head anteriorly is completed and in the position of central occlusion it reaches the base of the posterior slope of the articular tubercle. Due to the increase in functional load, the central part of the articular disc becomes somewhat thinner, while its peripheral parts remain thickened. The functional area of ​​the articular fossa decreases, the joint capsule takes the form of a truncated cone.

The TMJ has a complex system of blood supply and innervation – there is a wide network of vascular anastomoses (Fig. 4). This feature of the TMJ at the same time creates favorable conditions for the spread of infection from the border areas to the joint and vice versa. Nerve elements are numerous, located around the joint in a loose, fibrous stroma, often perivascular (Fig. 5).

Rice. 4. Temporomandibular joint. A wide network of vascular anastomoses in the soft tissues of the periarticular region. Stained with hematoxylin and eosin, ×4.

Rice. 5. Temporomandibular joint. Nerve trunk in soft tissues perivascular. Stained with hematoxylin and eosin, ×10.

A characteristic feature of the TMJ is the presence of outgrowths (villi) on the synovial membrane, which are the focus of interoreception. Villi are reactive structures having club-shaped and leaf-shaped forms, located in certain areas of the synovial membrane of the joint. They are absent in the fetus and newborns. Up to 1-2 years, only a small amount of villi appears. At the age of 3-6 years, due to an increase in the functional load, the number of villi increases significantly. In children 10-14 years old, villi of a complicated form are found, and at an older age they are located in large numbers not only in the posterior sections of both cavities, but also on their outer walls. With age comes the involution of the villi, which undergo degenerative changes.

TMJ is also characterized by anatomical and functional features inherent only to it. Both joints are a closed kinematic chain. Movements in one joint lead to a change in the position of the articular head in the other. The joint is biaxial, incongruent, “muscular” type. Musculature determines both the relationship of the elements of the joint, and the main phases of articular movements. The unilateral attachment of the muscle to the disc, which is characteristic only for the TMJ, prevents the disc from slipping back with a strong closure of the jaws and forward with a wide opening of the mouth (Fig. 6).

Rice. 6. Temporomandibular joint. Unilateral attachment of the muscle to the articular disc. Stained with hematoxylin and eosin, ×10.

Studies conducted by many authors have shown that the dentition is a very complex physiological system with characteristic features. This system goes through a peculiar way of development and functional differentiation, which can be traced in dynamics both on individual links of the articulatory chain and on the entire masticatory apparatus as a whole. A vivid example of the peculiar development of the dentoalveolar system is the complete replacement of morphologically and functionally complete organs – temporary teeth with permanent teeth. Such a replacement of organs does not occur in any physiological system, as well as the laying of organs after birth.

The presence of large common arteries and a complex, double intraorgan network of anastomoses characteristic of each masseter muscle, as well as numerous extraorgan anastomoses of the arteries feeding these muscles, ensures a full blood supply to both individual sections of each muscle and the entire complex of masticatory muscles during their differentiated and joint functioning (Fig. 7).

Rice. 7. Temporomandibular joint. Intramuscular vascular anastomoses. Stained with hematoxylin and eosin, ×40.

The organic relationship between the chewing muscles is manifested not only in the commonality of the arteries that feed them, but also in the direct connection of these muscles with all structures of the dentoalveolar system. In this regard, morphological changes in one of the links of the articulatory chain entail changes in the entire chain. Thus, the eruption of temporary teeth is accompanied by the growth of the alveolar processes of the jaws in height and width, as a result of which a new bite height is established, which in turn leads to an increased growth of the entire masticatory muscles. In addition, morphological changes in the elements of the TMJ occur, the relationship between them improves. In this case, the articular head moves from the distal extreme position to the center of the glenoid fossa. Such a functional and morphological connection is observed not only with the normal, harmonious development of the masticatory apparatus, but also with pathological changes in one or more links of the articulatory chain. For example, the defeat and destruction of the second temporary molars due to complicated caries lead to a violation of the formation of the height of the central occlusion, a decrease in masticatory function, a slow growth of the alveolar processes of the jaws and the formation of the roots of permanent teeth, their belated eruption, intraosseous movement of the crowns of permanent teeth and often the formation of occlusal disorders.