Longtime BBC radio 2 broadcaster Zoe Ball revealed on Instagram recently that she suffers from a painful jaw condition which causes her to “wake most days with awful headaches from tension and jaw clenching”.
The condition Ball suffers from affects her temporomandibular joint (TMJ). Although Ball refers to the condition as “TMJ” in her post, the medical name for this condition is actually temporomandibular joint disorder (TMD). It commonly causes headaches, pain and clicking in the jaw.
TMD is relatively common, affecting up to 12% of the population – although there’s variation across continents, with South America showing the highest prevalence at 47%.
The TMJ is a joint on either side of the skull that provides movement between the mandible and the temporal bone of the skull. It’s controlled by muscles and is used in talking, facial expressions and chewing. Due to its use in several processes, it’s susceptible to overuse and injury – leading to TMD.
One of the main causes of TMD is bruxism (clenching or grinding your teeth). This can happen during the day or while sleeping. Around 22% of the population experiences bruxism – though there’s significant regional variation here as well, with North Americans experiencing the highest prevalence of sleep bruxism (affecting around 31% of people).
Other causes of TMD include erosion and misalignment of the discs that cushion jaw movements – leading to clicking and popping. The cartilage within the joint can also be damaged by arthritis. TMD is typically seen in women over the age of 50.
Trauma to the joint from falls or while playing contact sports can also lead to TMJ. In fact, studies show between 38-57% of people who have TMD have a history of trauma to the jaw. Contact sport athletes (such as boxers) have extremely high rates of TMD – as high as 77% in some cases.
TMD is about two times more common in women – although men who develop the condition tend to experience symptoms at a younger age compared to women.
It’s not entirely clear why TMD is more common in women, but researchers have proposed a couple of possible mechanisms. Studies have shown that women create higher pressures in their TMJ compared to men, which might partly explain the higher incidence. Researchers have also proposed that hormones, such as oestrogen, may have a role in the condition.
There’s also a genetic link for developing TMDs – but it appears this isn’t the only cause. Whether or not a person with a gene for TMD develops the condition depends on whether they’ve had a previous injury to the joint, their hormone levels and lifestyle.
Some studies have also linked TMD to certain occupations, such as musicians, dentists, office workers and people working highly demanding jobs. Research also potentially suggests that work-related stress may also be a cause – though more research is needed to prove his link.
Many different symptoms can be indicative of TMD. The most common are headaches, the jaw clicking, popping or locking with pain, limited range of mouth movement, muscle tenderness, dizziness, as well as pain which can spread behind the eyes, in the face, down into the neck, shoulder and back.
One of the reasons TMD can be so painful is because the nerves in this region are highly sensitive. There’s also evidence that the fascia (the connective tissue that envelops the muscles and bones) are also implicated in TMD. Fascia has the second highest number of nerves in the body, after the skin, so the pain can be excruciating.
Imaging studies have shown there are changes in the nerves that sense pain in people with TMD. These nerves show increased sensitivity, as well as changes in their structure which impacts the muscles they control. People with TMD also show changes in brain areas that modulate pain. These functional changes correlated to pain duration, intensity and unpleasantness.
People with TMD may also experience wider central nervous dysfunction – with the nerves that control other body process becoming implicated. This may be one reason why people with TMD have a higher likelihood of having conditions such as IBS.
For many people, the symptoms and pain of TMD will disappear on their own – particularly if the trigger (such as stress) is identified and treated.
Pain can also be managed with painkillers (such as paracetamol or ibuprofen). You may also want to eat soft food or avoid chewing gum to reduce the stresses on the TMJ. For more severe pain and symptoms, stronger prescription medications (such as benzodiazepine, amitriptyline or gabapentin) may be helpful depending on the underlying cause.
In more severe cases, you may be given splints or night-guards to help stabilise the jaw and reduce tension on the TMJ. These treatments can be very beneficial.
Botox can also be used in cases where the muscles are the underlying cause or source of pain. This will help reduce the strains the muscles are putting on the TMJ. However, Botox isn’t effective in all cases, one study suggests 15% don’t report improvement. Cognitive behavioural therapy can also be beneficial in helping with pain and negative thoughts.
Surgical treatments are a last resort, usually done is cases where TMD is being caused by changes to the biting mechanics of the mouth. Approximately 5-10% of cases will require surgery. This permanent surgery replaces the cartilage disc with cartilage from the ear or nearby muscle. People who have had surgery show good symptomatic improvement.
TMD can be an annoying condition – but for most people, the pains are only temporary. If you’re finding your symptoms last more than a few days, it’s sensible to get them professionally checked.
Adam Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
