Medically reviewed by Brittany Ferri, PhD
“Is teeth grinding considered TMJ?”
“Are bruxism and TMJ the same?”
“Is my teeth grinding causing TMJ?”
These are questions that many people ask when they experience discomfort or hear clicking sounds in their jaw, and have been told by their dentists that these likely happen because they grind their teeth. But while the terms “teeth grinding” and “TMJ” are often used interchangeably, they refer to very different issues related to jaw health.
Teeth grinding, or bruxism, is a condition where a person grinds, gnashes, or clenches their teeth, either unconsciously while they sleep or subconsciously while awake. TMJ, on the other hand, stands for temporomandibular joint disorder (more accurately abbreviated TMD), which affects the joint that connects your jawbone to your skull, leading to pain and dysfunction in the jaw joint and the muscles that control jaw movement.
In this article, we will delve into the distinctions between bruxism and TMJ disorder, explore how teeth grinding can contribute to TMJ disorder, and discuss effective management strategies for TMJ pain.
What are TMJ disorders?
Temporomandibular disorders (TMJ disorders or TMD) encompass a range of conditions impacting the joints connecting the jawbone to the skull and the muscles that facilitate jaw movement. These disorders are marked by pain around the face and in front of the ear, restricted jaw movement, and locking/popping sounds from the joints during movement.
TMJ disorders primarily manifest as pain-related issues, including muscle pain, headaches linked to the TMJ, and joint pain, as well as mechanical problems like disc displacements and joint degeneration. These conditions can affect one or both sides of the jaw joint and vary in severity, potentially affecting one’s ability to speak, chew, swallow, yawn, and breathe.
What is Bruxism?
Bruxism is a behavior characterized by the involuntary teeth grinding, jaw clenching, jaw bracing (tensing up jaw muscles without teeth touching each other), and thrusting of the jaw (holding the jaw in a forward position).
These unconscious jaw behaviors can occur during sleep (sleep bruxism, or SB) or while awake (awake bruxism, or AB). Both conditions, though related, manifest differently and have distinct triggers.
Sleep bruxism occurs unconsciously during sleep and is often linked to arousals or disruptions in sleep patterns, primarily characterized by teeth grinding or clenching. On the other hand, awake bruxism happens while the person is awake and is usually associated with stress, anxiety, or concentration. It involves a wider range of activities—not just grinding and clenching but also nail-biting, excessive gum chewing, tooth tapping, tooth pressing, tongue pushing, tongue sucking, chewing on the inside of cheeks, lip biting, biting on pens or other hard objects, jaw bracing, and thrusting of the jaw.
Does bruxism cause TMJ disorders?
Because both TMJ disorders and bruxism affect similar anatomy, share common symptoms (jaw pain, facial pain, and headaches) and have many of the same risk factors (smoking, poor sleep quality, sleep-related breathing disturbances, and stress), it’s easy to assume that bruxism directly causes TMJ disorders. The idea is that chronic grinding and clenching put pressure on the jaw joints and muscles, potentially causing strain over time.
Another theory is that the repeated muscle contractions from bruxism can lead to muscle fatigue and discomfort, often manifesting as facial pain. Many dentists and TMJ specialists also believe that teeth grinding is a significant causal factor in developing TMJ, advising patients that their teeth grinding behavior contributes to their TMJ symptoms. However, the direct causal links between the two are not as straightforward as you think.
So far, observational studies show that bruxism does not cause TMJ disorders although it can worsen TMD symptoms. It also seems there’s a stronger relationship between awake bruxism and TMJ disorders than there is between sleep bruxism and TMJ disorders.
Not all individuals with sleep bruxism experience pain, or end up developing TMJ disorders. Conversely, not all TMD patients have a history of sleep bruxism. In studies that kept track of participants’ jaw behavior and muscle activities during sleep, people with TMD pain do not always show higher muscle activity or more frequent teeth grinding episodes during sleep compared to healthy individuals.
On the other hand, there is more supporting evidence that the parafunctional habits associated with awake bruxism (teeth grinding / clenching during the day, excessive gum chewing, clenching, tooth tapping, tooth pressing, tongue pushing, tongue sucking, lip biting, jaw bracing, and jaw tension) are strongly linked to chronic, painful TMJ disorders. People with these behaviors are about 17 times more likely to have chronic, painful TMJ disorders compared to those without these habits.
Furthermore, symptoms of TMD (pain, mechanical issues, and stress/anxiety) might also cause more awake bruxism behaviors. For example, jaw pain on one side might cause someone to chew more on the other side or at an awkward angle, causing strain and increasing the risk of further TMJ disorders.
This is why one of the suggested interventions for TMJ disorders is behavioral and physical therapy to become more aware of oral behaviors and positions that tend to exacerbate TMD, relearn behaviors to put the jaw in a relaxed position, and develop confidence to move the jaw in a more natural way.
In short, understanding the nuanced relationship between bruxism and TMJ disorders is crucial for effective management and treatment. While bruxism, especially awake bruxism, can exacerbate TMD symptoms, it is not a direct cause of TMJ disorders. Addressing comorbid conditions such as allergies, chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, and sleep disorders (which are all strong predictors of TMJ disorders) can provide a more comprehensive approach to managing the disorders. By considering the broader range of contributing factors and incorporating behavioral and physical therapy, individuals can achieve better jaw health and overall well-being.
What to do if you have TMJ disorders?
If you’re grappling with TMD, you might wonder if addressing your bruxism could resolve the issue. While mitigating bruxism can alleviate some symptoms due to the interconnected nature of these conditions, it is not a standalone cure.
Most individuals with TMD experience mild or sporadic symptoms that often resolve naturally over time. And there are shared strategies beneficial for both bruxism and TMJ disorders. These include being mindful of habits and emotional states that exacerbate TMD symptoms. Implementing self-care routines to ease jaw tension and pain can also significantly reduce symptoms associated with both conditions.
Below, we explore some of the most prevalent treatment options available.
*Note: For more information, the TMJ association has some helpful guide which can be found here: https://tmj.org/living-with-tmj/treatments/*
Self-Care
Temporarily eating soft or blended foods, applying hot or cold compresses, self-massage, and taking over-the-counter NSAIDs (non-steroidal anti-inflammatory drugs) may help ease the symptoms of TMJ disorders.
Physical Therapy
Therapeutic jaw exercises, that is, physical therapy focusing on the jaw, neck, head and shoulders can improve coordination, muscle strength, and mobility. Passive stretching may improve muscle strength and TMJ range of movement and, in addition, may also help overcome fear of moving your jaws. These exercises, often part of self-care programs, help reduce pain and improve jaw function and mobility.
Behavioral Therapies
Behavioral therapies, including biofeedback, cognitive behavioral therapy (CBT), habit reversal, and relaxation techniques, are increasingly being integrated with self-care practices to address parafunctional oral habits such as clenching, grinding, and biting objects, which can aggravate temporomandibular disorders (TMDs). These therapies are designed to enhance awareness of these habits and their triggers, facilitating the adoption of a relaxed jaw position as an alternative.
For instance, patients are taught to recognize that their teeth should only make contact during eating or swallowing, and that constantly bracing the teeth can lead to significant damage. A useful mantra for patients is “lips together, teeth apart,” which they are encouraged to repeat to themselves when they catch themselves engaging in their old habits. To reinforce this practice, reminder Post-It notes bearing this phrase can be placed in high-stress areas such as their car, work desk, or computer. These reminders have proven effective, especially when supplemented with random alerts set on their smartphones to periodically check their jaw position.
However, the management of these disorders extends beyond simply learning to relax the jaw muscles. More comprehensive approaches such as broad-based relaxation skills or mindfulness training have been shown to be highly effective in managing chronic pain and can significantly enhance the treatment of these specific behaviors.
Occlusal Appliance (splints, mouthguards)
Occlusal appliances, including stabilization splints and mouthguards, are frequently recommended for managing TMD pain. These devices are non-invasive, reversible, and can help relax jaw muscles and lessen strain on the temporomandibular joints. There is substantial evidence suggesting that these appliances offer moderate effectiveness in relieving TMD pain in the short-term, primarily by enhancing the wearer’s awareness of their jaw positions and behaviors. Given what we know about the relationship between TMD and awake bruxism, these splints might have to be worn during the day as well to increase their effectiveness.
The National Institutes of Health (NIH) brochure on TMJ advises that if a splint is used, it should be for a limited period and should not permanently alter the bite. And if the splint leads to increased pain, it is recommended to discontinue its use and consult a healthcare provider.
Similar to bruxism, studies found no evidence that occlusal adjustments (orthodontic procedures to change the way your teeth and jaws are aligned) are effective in the treatment of TMD. Therefore, orthodontic procedures for treatment of TMD is not recommended, especially since this therapy can be non-reversible.
For more information on various types of mouthguards and their appropriateness for TMD-related issues, please refer to this detailed article from the TMJ Association.
Surgery
Currently, there is a lack of long-term clinical trials evaluating the safety and efficacy of these surgical options (arthroscopic surgery, arthrocentesis). Furthermore, there are no clear guidelines and evidence to determine which patients might benefit most from surgery. Given the mixed outcomes—where some patients experience relief while others see no improvement or even a worsening of symptoms—and the often irreversible nature of these procedures, surgery should generally be considered a last resort. Lack of response to conservative treatments does not necessarily justify the decision to undergo surgery. This is why the NIH advises TMD patients that “[S]urgical treatments are controversial, often irreversible, and should be avoided where possible.”
Conclusion
The question of whether bruxism directly causes pain and TMJ disorders does not have a simple answer. While bruxism can contribute to and exacerbate these conditions, it is typically not the sole culprit. Understanding the multifactorial causes of bruxism, pain, and TMJ disorders is crucial for effective diagnosis and treatment. As research continues to evolve, it is hoped that clearer connections can be drawn to aid in better management strategies for those affected by these challenging conditions.
