Do you have a displaced or perforated TMJ disc? (or worried you have?)
Today's post is for you.
Not sure what TMJ is?
TMJ stands for temporomandibular joint dysfunction.
The temporomandibular joint is one of the most frequently used joints in the whole body. So it just makes sense that this joint could develop any number of dysfunctions over the course of a person's life.
In this article, learn about TMJ disc displacement and perforation, what it is, how it happens, warning signs and symptoms, diagnostic and treatment options.
What is the temporomandibular joint?
The temporomandibular joint is the joint that connects the upper jaw to the lower jaw. It sits just in front and slightly above the ear on each side of the head.
This is a particularly powerful joint that acts more like a sliding hinge than a true joint, permitting the jaw to move in ways that most joints could not accommodate.
There are three unique aspects to this joint that makes it unlike any other joint in the body.
1. It is actually a double joint.
According to the American Academy of Craniofacial Pain (AACP), the reason for this is because the temporomandibular joint is not just a single joint but actually is two joints (one on each side of the head) connected together by the jawbone.
2. The two joints are fused together.
A second unique facet of the temporomandibular joint is that the connecting jawbone acts to fuse one joint to the other, meaning when one of the pair moves, the other must move as well.
When the teeth move, both joints must move in such a way to promote optimal bite alignment, which can throw one or both joints into a situation of stress and strain.
3. There is a cushioning disc inside each joint.
This disc sits in the midst of the joint but can move on its own. Because it can move independently but is connected to each joint in multiple ways, it can also get pushed out of place, which the AACD calls "internal derangement."
What is TMJ disc displacement and perforation?
Understanding what makes the temporomandibular joint itself unique as well as unusually complex can shed light on how TMJ disc perforation and displacement occurs.
TMJ Displacement and perforation is one type of internal derangement of the TMJ disc.
There are two aspects to this disorder: displacement and perforation.
As was briefly alluded to earlier, disc displacement can occur when the temporomandibular joint is forced to move in ways that override the stability of the joint structure itself (such as when there is a bite misalignment).
This, then, can force the cushioning disc to be displaced. There are two types of displacement: with reduction and without reduction.
When the disc is displaced to the rear of the head (anterior position) the condition is called displacement without reduction.
When the disc is displaced towards the front of the head and just at the front edge of the condyle, the "ball" end of the lower jawbone, the condition is called displacement with reduction.
Disc thinning can in time lead to perforation, as can misuse of the joint itself and some health conditions.
Disc perforation is considered a later-stage manifestation of disc displacement that is often triggered by unaddressed or inadequately addressed displacement issues.
In some cases, prior attempts at surgical correction that led to formation of scar tissue damaged and weakened the disc, leading to perforation.
In other cases, displacement with reduction created thinning of the disc over time which then led to tearing or perforation.
Often, symptoms can last for months or years before the patient is properly diagnosed. This is because many of the symptoms of disc displacement and perforation can be mistaken for other health conditions (migraine headaches can be a particularly confounding symptom for patients and care providers alike).
What causes TMJ perforation and disc discplacement?
A number of issues and health conditions may cause disc perforation and/or disc displacement either with or without reduction.
In some cases, misuse of the joint over time can lead to displacement and/or perforation. In other cases, there may be an underlying genetic health condition that is a contributing factor to displacement or degradation of the joint.
These are the most common known causes for disc perforation and/or displacement:
Trauma or injury
This can be particularly common when the patient plays contact sports. Any kind of blow to the head can injure the jaw joint and its fragile disc.
Whiplash, such as the kind sustained from amusement park rides or vehicle incidents, can also impact the temporomandibular joint.
TMJ disorders can be genetic (heritable). Patients may discover that one or more close relatives also has joint or joint disc issues.
Arthritis can cause improper function and derangement of the jaw joint over time. Genetic (heritable) forms of arthritis such as rheumatoid arthritis and osteoarthritis are more frequently linked to cases of TMJ displacement and perforation.
Diseases of the connective tissue.
Certain diseases that trigger chronic inflammation of the connective tissues of the body can also have an impact on the jaw joint, causing symptoms of displacement and perforation.
This is particularly the case where the connective tissues are slow to repair, are looser than normal or are predisposed to scar tissue buildup after trauma.
Bruxism, or jaw clenching and/or teeth grinding, often occurs at night while the patient is asleep. For this reason, it can be particularly difficult to link bruxism with disc displacement and perforation until the condition is already well underway.
Often bruxism is first noticed by the patient's dental care provider. Chronic bruxism can cause tooth wear and bite misalignment which can then lead to joint pain, popping and derangement.
What are the symptoms and warning signs?
The symptoms and warning signs of TMJ displacement and perforation can span the gamut from painless clicking to severe and chronic migraines.
These are the most common patient-reported signs and symptoms of TMJ disc issues from mild to severe. Some symptoms may be intermittent while others, such as the popping sound and inflammation of surrounding tissues, is more likely to be chronic.
Symptoms can affect both joints (left, right) or just a single joint.
Sounds of popping or clicking when the jaw joint is moved, with or without pain.
Pain while chewing (sometimes only with hard foods).
Limited jaw mobility.
Jaw joint "locks" in the closed or open position.
Inflammation in the surrounding tissues that causes swelling, tenderness, pain.
Morning jaw locking or freezing.
Muscle spasms around either joint or both joints.
Facial pain or pain above the ear or earaches.
Pre-existing bruxism (grinding or clenching jaw at night).
Toothaches (often also associated with bruxism).
Shoulder or neck pain.
How is disc perforation or displacement diagnosed?
For many patients, their family doctor or dental care provider is the first to notice the signs of disc displacement and perforation and put all the pieces of the puzzle together.
There are a number of tests that can be done to confirm the diagnosis.
Patient-reported symptoms represent an important part of the diagnostic process.
While a wide range of symptoms exist, certain symptoms tend to be present in the majority of cases of disc displacement and perforation, including joint pain, popping sounds and pain while chewing harder foods.
Individual and family medical history.
Trained providers will first take a thorough individual and family medical history, looking for evidence of heritable TMJ disorders, related co-occurring medical conditions, jaw joint use habits (including night time bruxism) and matching symptoms.
Hands-on physical exam.
The next step in the diagnostic process is typically a hands-on physical exam.
The provider will have the patient perform basic jaw movements, including opening and closing the mouth, moving the jaw from side to side, pressure tests to identify pain points and inflammation and listening for the sounds of popping or clicking when the joint is moved.
A number of different diagnostic tests can be helpful in arriving at a conclusive diagnosis.
The most popular tests including imaging (X-rays), MRI and CT scan and arthroscopy.
Imaging: X-ray images clearly show the teeth and jaw and can reveal small fractures or cracks caused by bruxism.
CT scan: CT scans are most useful to deliver fine detail about the bones of the jaw joint itself.
MRI: The MRI test can offer more detail about trauma or damage to soft tissues like muscles, tendons and the soft disc inside each jaw joint.
Arthroscopy: Arthroscopy makes use of endoscopic technology to insert a small tube equipped with an even smaller camera into the interior of the jaw joint itself. This gives the provider the ability to view the actual area and identify areas that have been damaged.
What treatment options exist?
A variety of treatment options exist depending on the nature of the diagnosis.
Watch and wait.
In very mild cases of displacement or perforation, it may be possible to adopt a "watch and wait" approach to see if the jaw joint will heal itself.
In this case, the patient is often directed to make use of over-the-counter NSAID anti-inflammatories and pain medications and some prescription medications, such as muscle relaxants and prescription-grade anti-inflammatory corticosteroid drugs.
Non-surgical treatment frequently makes use of all of the above with the addition of prosthetics such as night bite guards and oral splints.
Other helps can include gentle massage, physical therapy, lifestyle modification and even botox.
NOTE: We shared a few of our personal favorite options on our TMJ resources page too.
Surgical treatment can be effective but is often reserved as a last-resort type of treatment.
Minimally-invasive surgery can drain excess fluid away from the joint area to reduce inflammation and pain. Corticosteroid or botulism toxin injections into the joint can also help ease inflammation and pain, although these are temporary solutions that may need to be repeated periodically.
More invasive corrective measures using arthroscopy or open-joint surgery on the mandible or joint may be required if the joint locks persistently and other treatments do not resolve TMJ disc perforation or displacement.
In some cases where disc perforation and displacement is triggered by another known or previously undiagnosed underlying health condition, taking steps to treat that condition may resolve some or all of the symptoms the patient is experiencing.
By understanding the typical causes, symptoms, diagnostic process and treatment options, patients can avoid delaying treatment and inadvertently causing more harm to the sensitive and delicate temporomandibular joint.
Early detection and diagnosis can mean less invasive treatment is required, which can lead to an improved prognosis long-term.