The Temporomandibular joint (TMJ) is a hinge joint that connects your jaw bone to the skull. This allows for movement during talking, eating and chewing. Unsurprisingly this makes it the most used joint in the body.
Constant use and abuse of the joint can lead to inflammation and pain and this presents as a variety of symptoms and signs which are all characterised under Temporomandibular Joint Dysfunction (TMD). It is a common condition which appear in 60-70% of the population. 1 Women are at least four times as likely to suffer from the disorder.1 The dentist is well equipped with conservatively dealing with and managing pain in the jaws.
What Is the TMJ?
The TMJ is a special type of joint that works similar to a hinge as well as a ball and socket joint at the same time. This joint primarily is made up of the round upper end of the lower jaw called the ‘condyle’ sitting in socket at the base of the skull called the ‘articular fossa’. Between the condyle and the fossa there is a disk of cartilage which acts as a shock absorber or cushion which allows the jaws to move freely. Surrounding the joint there are supporting structures such as muscles, tendons and ligaments which all work together to help with its function.2
What Causes TMJ and Jaw pain?
There are two types of TMJ pain. The first type is TMJ pain that is related to an acute injury which includes trauma to the jaw such as whiplash from a car accident or a blunt force to the jaw joint itself. Majority of the time, minor acute injuries to the jaw joint are self-resolving and pain usually subsidies after time is given for the joint to heal after the incident. Sometimes, surgery is required but only in severe cases. Ultimately, the joint would feel better after the initial trauma has been resolved.
The second type of TMJ pain is more chronic in nature. This is more commonly known as TMD which is a persistent disorder of the jaw joint, surrounding muscles and the nerves surrounding the area which all result in facial pain. Micro and minor trauma to the area generally doesn’t result in significant pain; however, over time, this accumulates to the point where the body reaches its limit and then it potentially causes a lot of grief.3 Some of the causes linked to TMD include:
- Teeth grinding
- Teeth clenching
- Poor posture
- Stress and anxiety
- Arthritis and other inflammatory musculoskeletal disorders
- Hormonal changes
- Misalignment of the teeth (crooked teeth)
- Malocclusion of the jaw (incorrect bite)
- Insufficient/incorrectly developed jaws
Its important to understand that the TMD is a multifactorial and complex issue and that simply addressing one of the causes may not necessarily help with resolving the pain. As an example, parafunctional behaviours such as bruxism, clenching and grinding may all contribute to muscular muscle pain spasm. This may in turn, result in internal derangement of the cartilage that is helping the jaw move freely.4 The cause of the parafunctional behaviour however, may be linked to cognitive and psychiatric problems such as depression and anxiety. Successful management and treatment of the jaw pain involves correctly identifying and managing all the contributing factors.
What are the symptoms of TMD?
As TMD is usually chronic in nature and has many different causes, it can have many different presentations ranging from mild and sporadic pain to severe consistent and debilitating pain. The most common symptoms of jaw pain include:5
- Jaw soreness and discomfort
- Soreness in around the ear during normal function
- Locking of the jaw during opening
- Inability to open the mouth
- Limited jaw mobility
- Clicking, popping or grating of the jaws
- Pain behind the eyes
- Shoulder/arm pain
- Earaches or ringing in the ears (tinnitus)
- Teeth soreness or sensitivity
How is TMD diagnosed?
A comprehensive examination and investigation are always needed to confirm and diagnose TMJ pain. It is important to understand the causes and factors that may be contributing to the onset of chronic facial pain so as to ensure effective and successful treatment and management of the issue.6
Comprehensive health history.
The more information documented about the pain history, medical history, dental history and social history, the more treatment can be tailored to the individual and the higher the chance of successfully managing the jaw pain. Due to the multifactorial nature of TMD, it is important to understand all the possible causes of the jaw pain before commencing treatment
Recordings and measurements of the range of movement of the jaw joint, a thorough muscle palpation to see areas of myofascial pain, examination of the teeth and surrounding oral structures are all required to diagnose TMJ pain
Full mouth xrays such as 3D Cone Beam Computed Tomography (3D CBCT) and Magnetic Resonance Imaging (MRI) may be required to view the jaw joint and surrounding structures
A polysomnogram or sleep study is a comprehensive test that electronically sends and records specific physical activities while you sleep. This is to screen for any sleep disorders which may have been undiagnosed previously. Sleep disorders have a big link to jaw issues and TMD
How do I manage jaw pain?
There are several conservative treatments for the successful management of jaw pain.7 Depending on the specific diagnosis these could include:
- Dental orthotics, nightguards and splints
- Dental restorative work
- Jaw massage/stretches
- Heat and cold packs
- Anti-inflammatory medications
- Stress reduction and management
- Behavioural changes
- Visit to the physiotherapist, osteopath, chiropractor, myologist, masseuse
- Botox injection, anti-inflammatory injection
- Diet changes
In order to treat and manage TMJ pain effectively, it is important to understand that treatment may incorporate some or all of the above treatment modalities to address all the contributing factors.
- Sharma S, Gupta DS, Pal US, Jurel SK. Etiological factors of temporomandibular joint disorders. Natl J Maxillofac Surg 2011;2(2):116–19. doi: 10.4103/0975-5950.94463. Search PubMed
- Ferreira LA, Grossmann E, Januzzi E, de Paula MV, Carvalho AC. Diagnosis of temporomandibular joint disorders: Indication on imaging exams. Braz J Otorhinolaryngol 2016;82(3):341–52. doi: 10.1016/j.bjorl.2015.06.010. Search PubMed
- Scrivani SJ, Keith DA, Kaban LB. Temporomandibular disorders. N Engl J Med 2008;359(25):2693–705. doi: 10.1056/NEJMra0802472. Search PubMed
- de Leeuw R, Klasser GD, editors. Orofacial pain: Guidelines for assessment, diagnosis, and management. 5th edn. Chicago: Quintessence Publishing, 2013. Search PubMed
- Speciali JG, Dach F. Temporomandibular dysfunction and headache disorder. Headache 2015;55(Supp 1):72–83. doi: 10.1111/head.12515. Search PubMed
- Vogl TJ, Lauer HC, Lehnert T, et al. The value of MRI in patients with temporomandibular joint dysfunction: Correlation of MRI and clinical findings. Eur J Radiol 2016;85(4):714–19. doi: 10.1016/j.ejrad.2016.02.001. Search PubMed
- Indresano A, Alpha C. Nonsurgical management of temporomandibular joint disorders. In: Fonseca RJ, Marciani RD, Turvey TA, editors. Oral and maxillofacial surgery. 2nd edn. St. Louis, MO: Saunders/Elsevier, 2009; p. 881–97. Search PubMed