What is TMJ pain?

20 Oct 2018



First things first. TMJ stands for Temporo-Mandibular Joint. When referring to TMJ pain, this usually means pain at the temporo-mandibular joint. TMJ pain can also be labelled TMD or TMJD meaning temporo-mandibular dysfunction/disorder or temporo-mandibular joint dysfunction/disorder respectively. Ok, so for the rest of this article I will use TMJ to mean the joint and TMJD to mean the dysfunction or pain. People will often just say they have TMJ (meaning pain), but technically if someone says “I have TMJ” you could easily say, “yes, and so does every other human and most mammals (i think)”, as this just means they have a temporo-mandibular joint. But that is being really pedantic and annoying… moving right along.  


TMJD is a very common condition that we treat all the time. It would be one of the most common reasons people come to our clinic. Jaw clenching and grinding tend to be the most common causes of this pain and as most people clench or grind in their sleep at night, they usually don't have a sense of why they are getting pain in the first place. 


TMJD can be debilitating and at its worst can mean you can't chew solid food without pain. There are many different causes and some underlying issues that can be at the root cause, making this a tricky injury to treat and manage. 





Let’s start with the basics. What is the TMJ? This is where the temporal bone (side of the skull) meets the mandible (jaw bone). Where the mandible and temporal bones come together is a synovial joint. This joint actually has a disc just like our spine. This disc absorbs pressure as without this disc the pressure of chewing food would damage this joint.


The skull or cranium is actually made up of 8 bones. These bones are held together with sutures or connective tissue when we are born, to help the skull be more malleable so the head can fit through the birth canal. The sutures then fuse at around the age of 2 to become one solid bone. The 8 cranial bones are the ethmoid bone, frontal bone, occipital bone, parietal bone, sphenoid bone and 2 temporal bones (see picture). 






The muscles of the jaw:



Temporalis: This is the biggest of the jaw muscles and takes up a good portion of the side of your head. This muscle controls closing the mouth (elevation of mandible) and pulling it in (retraction of mandible).


Masseter: this is the muscle right on the side of your jaw bone or mandible (also involved in closing your mouth and retracting it). This is one of the most painful of the jaw muscles to be massaged.  

Pterygoids: these muscles live inside your mouth and are mostly only accessible from inside, using a glove. There are 2 pterygoids, the medial and lateral.  They control lateral deviation (side to side movement) and protraction (pushing the bottom teeth forward. 



Digastrics: these are located under your chin and connect the jaw to the base of the skull (mastoid process). They open the jaw (depress) as well as retract and deviate the jaw. 


Platysma: a big sheet of muscle that covers your throat and connects to your chest. They help to open your mouth. 


Mylohyoid: under the chin. They help to open the mouth (depression).


There are some other muscles that also help with jaw movement. 


What is TMJD?

TMJD (temporo-mandibular joint disorder/dysfunction) can be a complicated condition as there are many different presentations of TMJD. 


The symptoms of TMJD can include:

  • Pain in the TMJ

  • Pain in the muscles of the masseter (side of jaw), temporalis (side of head) or pain inside the mouth (pterygoids). 

  • Pain in the teeth - especially after dental work as the mouth can often be held open for extended periods of time and can aggravate the jaw. 

  • Clicking or clunking of the joint when chewing or opening the mouth. 

  • Difficulty chewing

  • Dislocation or locking of the jaw.

  • Headaches/migraines

  • Neck pain

  • Ringing or clicking in the ears


Some people may just have one of these symptoms, a few or all of them. When all the symptoms are present it is more serious and tricky to work on. 



Causes of TMJD?

There are many causes of TMJD and the assessment and treatment of this will be different depending on the cause. 

The most common causes are:

  • Grinding teeth or clenching teeth (bruxism) - usually at night while asleep. 

  • Misaligned teeth or jaw (malocclusion)

  • Always chewing on one side of the mouth - this can often happen after having tooth pain. You chew on the good side to avoid pain and then become accustomed to it. 

  • Osteoarthritis in the TMJ.

  • Disc damage to the TMJ. The TMJ has a disc just like in the spine, which has many. The 

  • Trigeminal neuralgia - a very painful issue with one of the cranial nerves that causes severe pain in the cheek and jaw. 

  • Fracture of the jaw leading to jaw dysfunction. 

  • Poor posture


What can be done?

The first step is figuring out what is going on with the jaw and what is causing the issue. 


Grinding or clenching: if your issue stems from grinding then remedial massage, active release techniques and dry needling can be beneficially to reduce the tension and pain. Long term though you will need to address the stress. Self massage and stretching can help to keep the tension and pain from building up. 


Misaligned jaw: rebalancing the jaw is key here. Releasing the tight muscles and strengthening the weaker ones can help to realign the jaw. If your jaw clicks on the left side, often the jaw is slightly coming out of the joint on the left. This could be because the muscles on the right side are pulling the jaw that way when you open it. Releasing the right side and then strengthening up the left side to prevent the jaw from deviating will be crucial to preventing the clicking. This can be a long road as it takes time to rebalance muscles. You can’t just do an exercise once and think it will magically fix it. 


Severe clicking or locking: if your jaw if locking up regularly or clicking and catching then there may be an issue with the joint. The TMJ, like any joint, can become degenerated. This is generally age related wear and tear, meaning this will happen to everyone. If you have had a trauma to the jaw or have a long history of clenching then you may have prematurely damaged this joint. Having X-rays and seeing a specialist dentist such as an orthodontist or neuromuscular dentist will be essential to rule this out. 


Osteoarthritis: Unfortunately at this point in history there isn’t a miracle cure for osteoarthritis, which is basically just wear and tear of the joints as we age. It can also be caused by a misaligned jaw, as it will keep running on the joint and degenerate it. There are lots of claims that injections such as Platelet Rich Plasma (PRP) or stem cells are the next generation of treating osteoarthritis, but at this stage it is very hit and miss. 


Managing the symptoms is key here. Massage and dry needling can help to loosen up the muscles and take pressure off the joint. Exercises for the jaw are also important as this can help to realign the jaw and also take pressure off the TMJ. We always asked about supplements like glucosamine and chondroitin, which have failed to win over scientists and researches and have negligible effects at best, especially on severe osteoarthritis.


Therapeutic Botox is becoming more popular for chronic jaw pain. Botox is injected into the main jaw muscles which basically paralyses the muscles temporarily. This can work wonders, but will only last for a few months before you will need a top up. Getting to the root cause and fixing it is always better than covering it up with bandaids. Botox is a toxin, it hasn’t been tested over long periods, it’s expensive (can be $1000’s if you get it through a specialist and not the local beautician) and if you do go to someone who isn’t medically trained in it then there is a risk of more serious side effects. 


In the worst case, surgery can be indicated, but like most surgeries there is a risk that it may not work and may actually make things worse. Once the jaw is modified it is hard to go back to the way it was and it can take years to get under control again.