Created By: Kendal Martin
TMJ, also known as TMD or temporomandibular disorder, is a pathology involving any or all of the following anatomical structures:1
- the temporomandibular joint
- muscles/ligaments/tendons surrounding the joint
- structures surrounding the joint such as the ears, neck, cervical spine, teeth, & face
Although TMJ technically refers to the joint itself, any pathology or disorder related to this region is often medically referred to as TMJ rather than TMD. TMJ is defined as any disease impacting the jaw joint, or the muscles responsible for dental occlusion and jaw mobility. Problems arise when an imbalance occurs within any of the structures in and around the temporomandibular joint. The typical TMJ disorders are specifically defined as: pain dysfunction syndrome, arthritis, dysfunction due to trauma, or internal derangement involving the articular disk. All of these disorders typically present with the same spectrum of symptoms and respond in the same manner to treatment. Patients with TMJ often present with symptoms related to the muscles of mastication and structures involved in joining the lower lower jaw (the mandible) to the skull ( the temporal bone). Many of these symptoms occur as a result of the physical stress on the structures around the joint.1,2
The most commonly involved structures are:2,3
- Cartilaginous disk within the joint
- Musculature of the Neck, face, and jaw
- Ligaments, nerves, and blood vessels surrounding the joint, mouth, and teeth
As identified in Magee's Orthopedic Physical Assessment4 there are 4 stages of Temporomandibular Dysfunction:4
Stage 1: Disk slightly anterior and medial on mandibular condyle; inconsistent clicking (may or may not be present); mild or no pain
Stage 2: Disk anterior and medial; reciprocal click present (early on opening, late on closing); severe, consistent pain
Stage 3: Reciprocal click present (later on opening, earlier on closing); most painful stage
Stage 4: Click is rare (disk no longer relocates); no pain
What is TMJ or Temporomandibular Joint Disorder
The Temporomandibular joint(s) is one of the most complex joints of the human anatomy. Like many of the joints in the body, it is a synovial, joint surrounded by synovial fluid for nutrition and lubrication. It is made up of a superior and inferior compartment created by the disk or meniscus within the joint cavity. The joint itself is comprised of 3 main structures: the articular or mandibular fossa of the temporal bone, the mandibular condyle, and an articular disk. The articular fibro-cartilaginous disk is strategically located in between the condyle of the mandible and the mandibular fossa of the temporal bone. In the healthy temporomandibular joint, the disk acts to absorb stress within the joint, as well as improve fluidity of jaw movement.3,4
Unlike many other joints, however, this bi-articular, hinge-type joint allows for rotation or pivoting movement, in addition to translation or sliding movements bilaterally within the jaw. In the upper compartment or cavity, translation, gliding or sliding movement occurs; therefore the rotation, or hinge movement takes place within the lower cavity. The rotation occurs first from the beginning to the midpoint of movement range. The lateral pyterygoid (upper head) muscle assists with this motion by pulling the disk anteriorly preparing for the rotation of the condyle. The rotation can then occur between the disks and the two condylar heads. This is where the disk becomes important in allowing for congruency and lubrication within the joint. The second type of movement at the TMJ is the gliding component. It occurs as a result of translational movement of the condyle and disk along the articular eminence of the temporal bone. Both rotation and gliding must occur for the jaw to fully open and close efficiently.2,3,4
One unique element of the TMJ is the type of end feel or limitation of movement created by the rigidity of the teeth at the point of occlusion. The resting, or open packed position, of the TMJ occurs when the mouth open, lips are closed, and the teeth are not in contact. The TMJ technically has two closed packed positions: a) with the teeth tightly clenched and with the mouth open to its widest point. As stated by David J Magee, author of Orthopedic Physical Assessment, the capsular pattern is the limitation of the mouth opening. Therefore, as the TMJ is often considered a "tri-joint complex" due to the role the teeth play, dental alignment is of vital importance in relation to the temporomandibular joint.4
Another reason the TMJ is such a unique and complex joint is that both sides of the jaw must work in combination with one another for the jaw to move properly. Due to the shape of the bones and cavities of the joint, the jaw may move up and down, side to side as well as protrude/retrude. Movement at the TMJ is a function of the ligaments and musculature surrounding the jaw region. As a result of the complexity of the TMJ, all involved structures (nerves, ligaments, bones, teeth, disks, connective tissue and musculature) must work in sync for maximal joint functionality.1,3
Patient history is an important element in assessing patients with suspected TMJ pathology. The following questions are ones that Magee4 suggests that all Physical Therapists should ask upon evaluation and subjective exam of these patients:
- Is there pain or restriction on opening or closing of the mouth?
- Is there pain on eating? Does the patient chew on the right or left? both sides equally?
- What movements of the jaw cause pain? do the symptoms change over a 24-hour period?
- Do any of these actions cause pain or discomfort: yawning? biting? chewing? swallowing? speaking? shouting?
- Does the patient breath through the nose or the mouth?
- Has the patient complained of any crepitus or clicking?
- Has the mouth or jaw ever locked?
- Does the patient have any habits that place stress on the TMJ, such as smoking pipes? cigarettes? leaning on the chin? chewing gum? biting the nails? chewing hair? pursing and chewing lips, continually moving the mouth? or any other nervous habits?
- Does the patient grind teeth or hold them tightly?
- Does there appear to be any related psychological problems (often accompany TMJ)?
- Are there any teeth missing or misaligned (causing grinding or altered closing of the jaw)? cross-bite/scissor-bite? overbite? under-bite?
- Are any teeth painful or sensitive?
- Does the patient have any difficulty swallowing?
- Are there any ear problems such as hearing loss, ringing in the ears, blocking of the ears, earache, or dizziness?
- Does the patient have any habitual head postures compacting or compressing on the TMJ (i.e. holding telephone on ear, reading or listing to someone while leaning on jaw)?
- Has the patient noticed any voice changes (can be caused by muscle spasm around TMJ)
- Does the patient have headaches?
- Does the patient ever feel dizzy or faint?
- Has the patient ever worn a dental splint?
- has the patient ever been seen by a periodontist, orthodontist, or endodontist?
If the answer to any or all of these questions is "YES", temporomandibular disorder is likely the cause of patient's symptoms.The next and most crucial step is to conduct a thorough examination of the tempormandibular joint and cervical spine1,4 [see VII. Diagnosis and VIII. Special orthopedic tests]
IV. Incidence/ Prevalence:
In the US alone, research shows that millions of people suffer from TMJ each year. It has even been suggested 20 to 25% of the United States population suffers from TMJ related symptoms, totaling some 30 million Americans diagnosed annually with TMJ disorders. Based on current research, it occurs most frequently in patients age 20 to 40 years old. It is more common in women more so than men, at an approximate ratio of 5:1. Some research has shown that sex hormones in the female gender can play a role in the occurence of TMJ3
The following chart is taken from a study conducted by Doctor of Dental Surgery, Barry C. Cooper1 assessing the commonality of symptoms within two large groups of patients with TMJ or TMD.
(in % of subject population)
|Symptom||Total Pop. (n=3681)||Treated Pop. (n=1182)|
|Any joint sounds||48.0||53.7|
|Pain in joint||52.4||56.9|
|Any local TMJ sxs||71.9||76.5|
|Otalgia (w/out Infection)||52.5||49.6|
|Any Ear symptoms||75.9||76.0|
|Pain in or behind eyes||37.7||36.7|
As paraphrased from the research conducted by Dr. Barry C Cooper’s1, these symptoms serve as an illustration of the typical symptoms occurring within the TMJ/TMD patient population
V. Clinical Presentation:
Some of the main symptoms and complaints associated with TMJ disorders may be any or all of the following:2,4
- Biting or chewing difficulty or discomfort
- Clicking, popping, or grating sound when opening or closing the mouth
- Bruxism (grinding of the teeth)
- Dull, aching pain in the face in and around joint
- Ear ache
- Frequent headaches
- Point tenderness of the jaw
- Hypertonicity of the jaw muscles
- Reduced ability to open or close the mouth
- Excessive movement of the jaw upon opening or closing the jaw
- Muffled hearing
- Neck or back pain
- "trigger points" (due to contracted muscles in jaw, head, and neck)
- Facial or dental pain
- Facial/jaw muscle fatigue and/or spasm
- Changes of dental structure
- Altered occlusion mechanics- cross-bite/scissor-bite, under-bite, over-bite
VI. Potential Etiologies:
For most people with temporomandibular joint disorders, the cause is unknown. Research has provided some potential causes for this condition, but they have not yet been consistently proven. These include:2,5
- Dental malocclusion or orthodontic braces
- Prolonged Stress and or tension
- Grinding or clinching of the teeth.
- Poor posture, i.e. forward head while working all day or looking at a computer for long periods of time
- Strain of face and neck muscles
- Having the mouth open for long periods of time
- Poor diet, eating habits, long term gum chewing
- Lack of sleep
- TMJ disk dislocation
- trauma or a blow to the face.
- subtle repeated traumas, like clenching the teeth or excessive gum chewing, nail biting or cradling a phone between your shoulder and the side of the head
- constant muscle spasm of jaw musculature
- developmental abnormalities of bones, joints, and/or muscles
Some causes have been proposed in relation to other conditions, but are not supported by research: rheumatoid or osteoarthritis, fractures, dislocations, and structural problems present since birth.2
VII. Diagnostic Tests:
Unfortunately, there currently are no evidence based testing available to formulate or support a valid diagnosis for TMJ disorders. One of the main reasons for this is the lack of clear causal factors of TMJ. Additionally, the particular symptoms present in all TMJ patients is unclear. Therefore, diagnosis and prognosis can be difficult to assess. As a result, many diagnoses are based upon several crucial elements of the patient's evaluation: the questionnaire previously discussed, subjective exam and description of symptoms, patient history, and a thorough exam of cervical spine, neck, head, face, and jaw.1,5If TMJ dysfunction is suspected, a thorough examination must be conducted to rule in or rule out these structures. There are many differential diagnosis that can cause some of the symptoms seen in TMJ patients however, so the exam is a crucial factor in ruling out all uninvolved structures and conditions.2,5
Some of the many pathologies that may mirror TMJ symptoms are as follows:
- facial pain due to muscle spasm/strain
- facial nerve pathology causing facial pain (facial-neuraglia)
- sinus or ear infections
- several types of headaches
- tumors around the head, cervical spine, and jaw
- systemic infections
Because TMJ is difficult to diagnose, referral may be necessary. Some of the types of doctors that may be used for referral are: primary care physicians, ear, nose, and throat doctors, dentists, neurologists, endocrinologist, chiropractors, TMJ specialists, rheumatologists, and chronic pain specialists. Patients may need to see more than one specialist to examine TMJ pain and symptoms present to attain a conclusive diagnosis; Health care providers that should be rather experienced with TMJ are: patient's primary care provider, a dentist, or an ear, nose, and throat (ENT) doctor, depending upon patient's symptoms.4,5
As a Physical Therapist, one must assess any and all structures surrounding the suspected area of pathology. Above, we previously discussed that the common areas of symptom referral within the TMJ are the cervical spine or teeth. Therefore, therapists must at least briefly examine the cervical range of motion, observing patients ability to perform movements actively, any deviations that occur, and if there is any abnormal movement of the the TMJ associated with cervical movement. 4
The next step is to assess the movement and range of the TMJ. To the left (Table 2) is an example of a physical exam used in a study assessing youth with TMJ complications.6 This should clearly be a more thorough exam than the cervical testing. PT should first assess the available movement of the mandible actively, observing all movements including: opening and closing, protrusion, retrusion, and lateral deviation or excursion. PT should then measure the mandible, assessing the distance from the posterior portion of the temporomandibular joint to the most distal aspect of the chin bilaterally, looking for any differences from right to left. Following measurement, Magee suggests testing the patient ability to swallow along with all other responses related to the 12 cranial nerves4.
Passive movement is not often performed within the temporomandibular joints, except for perhaps when assessing for end feel of the joint. The end feel upon opening should be tissue stretch, and upon closing, its a bony block provided by the teeth. Resisted isometric movements can be performed to assess the strength and quality of movement of the jaw. It may be difficult to perform these types of tests on the TMJ, but it can be done. The 3 types of resisted movement tests are a) opening or depression of the jaw, b) closing or elevation/occlusion of the jaw, and c) lateral deviation of the jaw to the right and left. 4
Another important aspect of diagnostic evaluation specific to the TMJ is an assessment of the patients ability to perform daily tasks and functions requiring use of the temporomandibular joint. This includes but is not limited to: chewing, swallowing, blowing, talking, and coughing. PT can mimic these tasks in the clinic, for example using a tongue depressor to have patient bite down in different locations, determining the location and severity of symptoms.1,4
The last and often most important element of the diagnostic exam is an evaluation of tjoint play. PT should first palpate the TMJ region to find the areas that are likely sources of pain. The main structures targeted with palpation should be the TMJs, the mandible, the teeth, hyoid bone (level of C2/C3), thyroid cartilage (level of C4/C5), the mastoid process, and the cervical spine. After palpating these areas to determine pain location(s), PT can then accurately assess the patients joint play of the TMJs. The movements commonly tested are: a) longitudinal cephalad and anterior glide, b) lateral glide of the mandible, c) medial glide of the mandible, and d) posterior glide of the mandible. Each of these should be done individually. After all of the previous elements of the examination have been completed, the PT should then be able to create a rather valid hypothesis regarding the patients diagnosis. 2,4
** NOTE: As TMJ is often difficult to diagnose, and there are not any research-supported causes of this condition, PTs or Primary Care physicians may refer the patient out for Diagnostic imaging such as film radiography or MRI to assess the joint contours and abnormalities to clarify the diagnosis **3,4
VIII. Evaluation/Special Orthopedic Tests:
Although there are not any valid research supported special tests used to diagnose TMJ patients, there are a few tests that can be used to support or negate a PT's Diagnosis:
This test is performed in patients with suspected TMJ in order to rule out a facial nerve pathology. It is typically performed in sitting, but can be performed in supine or standing. The PT simply taps on the masseter muscle and parotid gland with light pressure. A positive test defined by twitching of the facial muscles, specifically the masseter, indicating the presence of facial nerve pathology. One thing to note with this tes is the patients history, as low levels of calcium in the blood can also cause twitching of the facial muscles. This is something the PT must be aware of with a positive finding. As this could indicate a false positive, a positive finding mustn't be disregarded, but proves the decreased validity and reliability of Chvostek's sign.3,4
This test is conducted to assess the anterior dislocation of the disk. It is performed with patients seated in a chair in an erect position. The PT then places a cotton roll between the back teeth on the unaffected side. The patient is then instructed to bite down forcefully. If the patient experiences pain upon biting down, this indicates anterior disk location. If the patient experiences significant pain prior to this test, patient can be instructed to chew on the cotton roll rather than place significant stress on the joint by biting down. The modified chewing test is not as specific to anterior disk location but indicates TMJ involvement.
This tests is performed in the same position as the loading test. The PT stands in front of the patient, with his or her fifth digits in the patient's ears. The PT then instructs the patient to open and close the mouth while the therapist provides pressure anteriorly with pads of the fifth digit bilaterally. A positive test is noted by pain or discomfort upon opening and/or closing the mouth when pressure is applied by the therapist. A positive result is indicative of inflammation within the synovium of the TMJ.
IX. Conservative Treatment: 3,5,8,9
- NSAID's or low-dose try-cyclic medication for pain
- muscle relaxants
- Resting the joint
- Posture training and education
- jaw relaxation techniques
- stress relief techniques
- trigger point therapy/ischemic pressure for muscle spasm and pain
- Local anaesthetic injections into the joint
- TMJ mobilizations - dependent on findings of joint play assessment - i.e. distraction, lateral or anterior glides, etc.
- isometric exercises of the jaw
- Active Jaw muscle stretching
- Changes in diet & chewing mechanics education
- Education or purchase of maxillomandibular appliances(dental/bite guard, splint, or night guard, to prevent teeth grinding and correct bite)
- Avoidance of jaw movement at extreme ranges
- Light cervical mobilizations (based on the patient's sxs)
- Avoidance of chewy/sticky candy and chewing gum
Modalities are often only used for pain relief in patients that suffer from TMD. Research in this area of TMJ treatment is sparse. As pain is the main complaint of many patients with this disorder, the following treatments have shown up in current literature as possible therapy treatments to reduce pain in and around the Temporomandibular joint:
- Superficial or deep heat has shown to have an impact on some of the common symptoms of TMJ such as muscle tightness, inflammation, and limited opening of the jaw secondary to these complications. Heat packs and warm compresses can be used alone or in combination with physical therapy to minimize the complications of TMJ muscle tightness, and overuse. Thermotherapy can assist in allowing the muscles to relax. This not only allows for an increased range of motion of jaw musculature, but it can also improve mandibular symmetry.
- If TMJ symptoms occur as a result of trauma or acute injury, ice packs should be applied initially to decrease swelling and pain. Pain is the main complaint related to TMD and doesn't typically resolve immediately without surgery. As surgery is often a last resort, conservative therapy is optimal. Ice packs can be applied alone or in combination with physical therapy to reduce swelling and pain as symptoms persist.
As stated above, current available research has shown little evidence to support the use of other modalities in the conservative treatment of TMJ. An article published in 2007 in the American Family Physician Journal, states that there is evidence that both Iontophoresis and Phonophoresis are other valid options for pain control.11. Much of the research supporting their use was published in the late 1990's12, however futher research still needs to be conducted in order to prove the benefits of these modalities still hold true.
Based on Current Research, approximately 80% of TMJ patients can decrease or even alleviate symptoms with the application of conservative treatment. A thorough analysis of each patient is essential to determine the source of pain so that treatment can be individualized based on patients symptoms.8 Conservative management is always preferred over surgery as the TMJ is a small region and surgery is often difficult. However, if and only if conservative therapy fails, and no changes in symptoms are present at 2-3 weeks, there are several surgical solutions available.3,4
X. Surgery & post-op treatment:
- Arthrocentesis: the most basic type of surgical treatment for TMJ and is also the least invasive. There is very low risk with this type of procedure. Needles are inserted into the joint, flushing the joint with sterile fluids, attempting to free up the joint. On occasion, surgeons will also have to insert an instrument to free up the disk and allow for movement. This particular procedure is typical performed on patient that have restrictions in opening the jaw due to locking of the TMJ.^^3^
- Arthroscopy: the next option after atherocentesis. It is another means of placing the disk in its proper position. An incision is made directly in front of the ear. Through this incision, surgeons insert a unique piece of equipment containing a lens and a light. This technique allows the surgeon to assess the area in and around the TMJ. Depending on the patients symptoms the surgeon will either remove tissue that has become inflamed or align the disk and/or condyle causing alterations in movement. Sometimes just realigning the disk is not a permanent fix, so surgeons will often insert artificial ligaments and anchoring hardware into the jaw attaching it to the condyle. This is common surgical approach to TMJ. It has up to a 90% success rate, is said to have a significant impact on TMJ symptoms, and is an excellent approach for patients who face constant TMJ dislocation 3
- Discectomy: one of the surgical options for the most severe TMJ patients. The damaged portion of the joint, which is frequently the cause of dislocation, is removed, as it has been deemed irreplaceable. Once the disk is removed however, the patient may also experience decreased stress absorption within the joint, increasing the load or forces through the TMJ. There are no other allographic materials that are adequate replacements for the the removed portion of the joint, so typically it is left as is, simply without the articular disk; hence, increasing the liklihoood of degeneration in the future.3,8
- Condylar shave: the purpose of this type of surgery is to restructure the joint surface in temporomandibular joints that have begun the degeneration process. This is achieved by either reducing the growth plate, or removing osteophytes that have begun to form within the joint. As a secondary effect, the joint is also decompressed, but could potentially lead to further degeneration. There is no current research proving that this surgery is effective long-term. Some patients who receive this surgery may go on to need full joint replacement.3
- Joint Decompression: Most joint decompressions are performed via osteotomy of the condylar neck. This allows for symptom relief in patients with significant joint derangement. This surgery indirectly provides rest for the joint, and allows for the jaw to be realigned upon occlusion.8
- Joint Replacement (disk, condyle, fossa or total joint replacement):The part of the TMJ that has been damaged is completely removed. Depending upon the amount of damage, patients can receive either a partial or full joint replacement. In a partial replacement, either the fossa or the condyle is replaced. If the patient has had multiple surgeries or the joint is severely damaged then the surgeon will perform a full joint replacement, replacing both the condyle and the articular fossa. It is a rather safe procedure in which surgeons insert a prosthetic piece that replaces the previously damaged portion of the joint. Research states that all other non-surgical, conservative treatment options must have been attempted before surgery becomes an option.3
Post operative Care:3,10
- wound care
- ice and heat as directed
- liquid/puree diet involving little or no chewing
- bruxism control (prn)
- bite management
- limited movement until allowed to do so by surgeon
- active or passive activity as soon as patient is able in order to increase ROM and stretch muscles
- Follow up with doctor and surgeon as directed post-surgery
XI. Additional Web Based Resources:
- TMD/TMJ (temporomandibular disorders). American Dental Association Website. http://www.ada.org/public/topics/tmd_tmj.asp.
- Beuscher JJ. Temporomandibular joint disorders. Am Fam Physician. 2007;76(10):1477
- Hampton T. Improvements needed in management of temporomandibular joint disorders. JAMA. 2008;299(10):1119-1121.
- Scrivani SJ, Keith DA, Kaban LB. Temporomandibular disorders. N Engl J Med. 2008;359:2693-2705.
- TMJ Disorders. National Institute of Dental or Craniofacial Research. Published 2009. NIH Publications No. 06-3487. www.nidcr.nih.gov/OralHealth/Topics/TMJ/TMJDisorders.htm
XII. References (AMA format)
- Cooper BC. TMJ/TMD information. TMJ/TMD facial pain website. http://www.tmjtmd.com/information/. Published 2006. Accessed November 28, 2010.
- TMJ disorders. National Instititutes of Health MedlinePlus Website. http://www.nlm.nih.gov/medlineplus/ency/article/001227.htm. Updated 2010. Accessed November 29, 2010.
- Ingawale S, Goswami T. Temporomandibular joint: disorders, treatments, and biomechanics. Ann Biomed Eng. 2009; 37(5):976-96. http://www.springerlink.com.ezproxy.lib.vt.edu:8080/content/1864106v87hh3944/fulltext.pdf. Accessed November 26, 2010.
- Magee DJ. Chapter 4:Temporomandibular Joint. Orthopedic Physical Assessment. 5th ed. St. Louis, MO: Elsevier; 2008:203-230.
- Living with TMJD’s: a life-long challenge. TMJA: The TMJ association website. http://www.tmj.org/site/content/living-tmjds-lifelong-challenge. Published 2009. Updated 2010. Accessed Nov 30, 2010.
- Loddi PP, Ribeiro de Miranda AL, Vieira MM, et. al. Factors predisposing 6 to 11-year old children in the first stage of orthodontic treatment to temporomandibular disorders. Dental Press J Orthod. 2010; 15(3):87-93. http://www.scielo.br/pdf/dpjo/v15n3/en_11.pdf
- Konin JG, Wiksten DL, Isear Jr. JA, Brader H. Special tests for orthopedic examination: 3rd ed. Thorofare, NJ: SLACK Inc.; 2006:1-6.
- Sidebottom AJ. Current thinking in temporomandibular joint management. Br J Oral Maxillofac Surg. 2009; 47(2):91-4.
- Houle S, Descarreaux M. Conservative care of temporomandibular joint disorder in a 35-year-old patient with spinal muscular atrophy type III: a case study. J Chiropr Med. 2009; 8(4):187-92. http://www.ncbi.nlm.nih.gov.ezproxy.lib.vt.edu:8080/pmc/articles/PMC2786227/pdf/main.pdf. Accessed November 27, 2010.
- American Society of Temporomandibular Joint Surgeons. Guidelines for diagnosis and management of disorders involving the temporomandibular joint and related musculoskeletal structures. Cranio. 2003; 21(1):68-76.
- Buescher JJ. Temporomandibular joint disorders. Am Fam Physician. 2007; 76(10):1477-82.http://www.aafp.org.ezproxy.lib.vt.edu:8080/afp/2007/1115/p1477.html. Accessed March 13, 2011.
- Shin SM, Choi JK. Effect of indomethacin phonophoresis on the relief of temporomandibular joint pain. Cranio.1997; 15(4):345-8.