TMJ Disorders for Health Professionals


Temporomandibular Disorders generally fall into two broad categories:

  1. Intra-articular/TMJ pathology or
  2. Myofascial/muscular pathology 

There may be a psychogenic or a centralised element to the patient's pain as well. 

In spite of clear evidence of the difference between TMJ and myofacial pain, studies and "experts" continue to group these as one entity and may be due to some patients presenting with both. Currently, it is quite clear that the term TMD is an umbrella classification and not a specific diagnosis

The TMJ is an orthopedic joint like other joints in the body. It has synovium, a meniscus, is filled with synovial fluid and is prone to overuse and trauma. Despite many "expert" opinions regarding the TMJ behaving differently to other joints, any pathology that can affect other joints can affect the TMJ. Ie: arthritis, degenerative joint disease and disc perforations. 

This site will concentrate mainly on surgical conditions of the TMJ and their management. Internal Derangement and Osteoarthritis are the most common reasons for surgical referral. 

Below is one of many classification systems for TMDs which are all similar. 

  • Initial Diagnosis


    Specific TMD diagnosis is often difficult and challenging due to the diverse range of signs and symptoms but a good starting point is identifying and differentiating between an extra- and intra-articular disorder.

    A few questions to the patient can help differentiate this.

    Where is the pain?

    A good gauge in differentiating the primary pathology is the location of pain. If your patient points(with their finger) to the jaw joint, often the pathology will lie within the joint capsule. If your patients has difficulty localising the pain and uses there palm to locate the pain then often a myofacsial or combined problem exists. 

    Have you ever had locking of the jaw(closed or open lock)?

    These reported symptoms indicate internal derangement of the TMJ. The orthopedic and rheumatologic definition is any intra-articular condition that interferes with smooth joint function. The dental definition tends to focus on a displaced articular disc. 

    Limited mouth opening can indicate a displaced disc and chronic inflammation within the joint itself. An acute or chronic closed lock warrants surgical consultation and investigation. Studies have indicated that earlier intervention for anatomic derangements leads to better long term outcomes like other disease processes. 

    Has there ever been trauma to the face?

    Trauma to the TMJ is a common cause of internal derangment and can lead to post-traumatic arthritis. Chronic pain can develop if not addressed early. These are common occurences in our practice. Surreptitiously, a prolonged dental visit or general anaesthesia can also cause this with tearing and rupture of ligaments a possible cause. 

    Do you notice yourself clenching or has your partner told you that you grind your teeth at night?

    Microtrauma to the joint is also a common aetiologic factor in the TMJ disease. Clenching or bruxism can overload the joint and lead to chronic inflammation, synovitis, a displaced articular disc and degenerative joint disease. 

    Do you often have associated headaches with your jaw joint problem?

    Headaches and other vague symptoms are commonly associated with internal derangement and joint problems. 



    For the General Medical or Dental Practioner:

    Often the first imaging modality is an OPG. These can be used as a screening tool for ruling out dental caries and other gross pathology such as cysts and fractures. Occasionally, gross articular changes can be seen in the TMJ(See Figure). However, due to the limited amount of information available regarding the TMJ no soft tissue pathology nor subtle articular surface changes can be elicited. When possible, cone beam CT imaging should be requested which "includes TMJs and occlusion". 

    Gross Articular Changes in Right TMJ

    In this OPG, there are gross changes in the articular surface in the right TMJ. This represented a case of osteoarthritis. Often these changes are subtle and a CT or iCAT imaging is recommended. 

    Specialised Imaging Modalities: CT and MRI

    Cone Beam or Medical Grade CT: 

    Imaging of the TMJ with CT can elicit bony changes in the condyle. The classic signs of osteoarthritis are a decreased joint space, subchondral cysts and flattening of the articular surfaces. 

    This is a coronal CT section of a classic case of TMJ osteoarthritis with loss of joint space, flattening of the articular surfaces and subchondral sclerosis and cyst formation.

    MRI(Magnetic Resonance Imaging)

    This modality allows assessment of the disc position and amount of inflammatory change within the TMJ capsule itself. It also allows a dynamic assessment of the disc to observe whether it reduces or a "closed lock" is present. Other changes that can often be elicited are synovitis and joint effusion. 

    TMJ MRI demonstrating a bunched up and anteriorly displaced disc(dark area in centre of image)



    Most likely, specialist assessment will request these when appropriate. Various inflammatory markers and auto-antibody tests can be requested to complete the clinical picture. Some of these markers include ANA, Rheumatoid factors and CRP. 



    Various nerve blocks in the facial region are useful for ruling in or out an intra- or extra-articular problem. These can also elicit if central sensitisation may be present. Some diagnostic nerve blocks that are commonly used in our practice are:

    1) Intra-articular nerve blocks
    2) Muscular blocks
    3) Trigmeninal blocks including infra-orbital and the IAN in the case of neuralgias
    You should only undertake this if you are familiar with the anatomy you intend to examine. Intra-articular nerve blocks should remain within the realm of specialist practice. 
  • Referral Protocols


    A good starting point for patients wishing to seek specialist opinion, requiring diagnosis and initial non-surgical management would be Anita Nolan. She is the only medically registered(Medical Doctor) Oral Medicine Specialist in the South Island. She is our preferred choice due to her exceptional thoroughness, knowledge level and communication skills.  

    For patients requesting a surgical opinion, referral can be made via our website. Conditions that warrant surgical referral include a closed lock(mandibular opening of <35mm) and recurrent dislocations. 

    A detailed referral letter is always appreciated which should include patient symptoms, signs, medical history and previous therapy. 


  • Common Diagnosis


    Internal Derangement

    Internal Derangement is defined as any intra-articular condition that affect the smooth functioning of the joint. This can occur in isolation or with other TMDs. A common description taught in most dental schools is disc displacement with or without reduction. Although a simply definition, it gives the patient and clinican a basic understanding of joint mechanics. 


    The classic opening click occurs when the disc slips back onto the condylar head

    Disc displacement most likely occurs due to a traumatic event that leads an inflammatory response and displacement of the disc. This can be either microtrauma(ie: bruxism and clenching overloading the joint) or macrotrauma(ie: a fall or jaw injury). A small proportion of patients will have disease progression which can eventually lead to a "closed lock" and fibrosis of the joint.  


    Also known as degenerative joint disease. This occurrs when the internal derangement starts to erode the condylar surface affecting the bone structure. This can be due to wear and tear and commonly trauma. Crepitus is almost pathognomonic for OA. Pain can be constant and debilitating. This process is the same as osteoarthritis of the knee or hip. A total joint replacement may be a last resort treatment. 

    Myofascial Pain Dysfunction

    This affects the muscles of mastication. Clenching and bruxism are part of the syndrome which can lead to overloading of the TMJs. Myofascial pain dysfunction alone does not require surgical treatment. Often a pain management specialist can be of help if there is a pain syndrome. 

    Recurrent Dislocation

    This occurs when the condyle slips out of the glenoid fossa with the patient unable to relocate the joint with normal joint movements. Often the patient has to relocate the condyle physically with their hand or even needs this done in a medical facility. 

    Other entities include:

    • Condylar hyperplasia
    • Rheumatoid arthritis
    • Idiopathic condylar resorption
    • Tumours of the joint


  • Initial Non-Surgical Management


    Non-surgical treatment should be considered for all symptomatic patients with internal derangement or osteoarthritis. For mild or moderate pain and dysfunction, this treatment alone is often sufficient. Patients with severe pain and dysfunction may also be treated non-surgically, but if adequate reduction of symptoms does not occur within 2-3 weeks, surgical consultation is indicated. In instances of closed lock, regardless of the degree of pain, early surgical consultation is indicated.

    If non-surgical measures fail and little or no improvement occurs within 1 to 3 months, surgical consultation is warranted. Long term conservative measures are NOT CONSERVATIVE

    Non-surgical treatment has the following aims:

    1. Reduction of joint loading
    2. Maximizing joint mobility
    3. Reduction of inflammation
    4. Control of pain

    Baseline non-surgical therapies include the above which have varying degrees of success.

    Intra-oral Appliances

    We are underwhelmed by the success rates of intra-oral appliances in advanced internal derangement. These may help in cases of early internal derangement. Studies have indicated that appliances only acts as a placebo in a large proportion of patients. These work in theory by decreasing the load of the jaw joints and changing proprioceptive feedback. They do not correct or manage underlying pathology. However, some clinicians still believe they are the panacea for all facial pain. These must be prescribed selectively. 

    NSAIDs and Other Pharmaceuticals

    Joint pain is inflammatory. For pain management, NSAIDS can be added to the regime for a reduction in inflammation. Other pharmaceutical therapy can include Tricyclic Antidepressants which have an analgesic effect and aid disruptive sleep patterns. These should generally be administered by medically qualified personel. 


    Physiotherapy can also be used to treat functional issues and pain. It plays a major role in post operative rehabilitation. The physiotherapists we work with in Christchurch include:

    We also work with other physiotherapists in Auckland and Dunedin when necessary:

    Auckland:  About Faces 
    Dunedin:   Recovery Room

    Other modalities that can be employed in the non-surgical setting include but not limited to:

    • Trans-cutaneous electrical nerve stimulation(TENS)
    • Biofeedback with counselling and or psychological evaluation:
    • Muscle relaxants 
    • Behavior modification: Diet load reduction in the TMJ is achieved by modifying the patient’s diet to reduce joint loading from forces of mastication, ie: non-chewing diet such as liquid or pureed food.
    • Botox injections into the masseteric muscles has also been used to reduce clenching and bruxism

    Outcomes of Non-Surgical Management

    A summary of results of evidence-based studies on nonsurgical therapy for internal derangement[1] [2] [3] [4] [5] [6] is listed:

    • Most patients have improvement in signs and symptoms with time
    • Palliative care (NSAIDs, education, diet modification, exercises) seem to be as effective as more costly appliance therapy
    • Occlusal appliances do not change disc position
    • Occlusal stabilization appliances may reduce myalgia and arthralgia
    • Although patients with internal derangement improve with time, the length of time for symptoms to improve is not clearly identified
    • Treatments can have a powerful placebo effect

    A long-term evaluation of temporomandibular dysfunction patients; including myofascial problems, internal derangement, and combinations of both, showed comparable levels of successful treatment outcome with conservative measures and advice, or advice alone. A small proportion of these (12%), found no benefit from conservative measures or advice. These tended to be patients with more severe chronic symptoms and suggests that all patients should first be offered conservative measures, and those with little or no improvement should be considered for surgical intervention.  Ninety-percent of internal derangement patients improve with non-surgical measures, 8% will require surgical intervention and 2% develop chronic pain[7].

  • Surgical Treatment Modalities


    The following surgical procedures are accepted and effective methods for treatment of joints with ID/OA:

    1. Arthrocentesis/Arthroscopy
    2. Arthroplasty
    3. Total Joint Replacement

    Surgical Treatment

    Surgical Treatment for ID/OA has the advantages of effectiveness and rapid response. Surgical consultation should be offered to patients with documented ID/OA and in whom severe pain and dysfunction persists after a trial of non-surgical therapy. Early surgical consultation is especially important in cases of closed lock where delay in treatment can accelerate the progression of ID/OA.

    Acute closed lock/intra-articular hematoma/anchored discphenomenon is a TMJ “emergency”. Urgent arthrocentesis or arthroscopy is the mainstay of management. Patients tend to be younger and present with an acute severe restriction of opening. In roughly 90% the symptoms will resolve without further progression if they are dealt with early, otherwise they risk joint fibrosis if left untreated[8]

    Outcomes of Surgical Treatment

    Clinical research of surgical treatment results of internal derangement is summarized here6:

    • There are no prospective, randomized controlled or double-blinded trials. Only case series and comparison of preoperative and postoperative signs and symptoms are available.
    • Arthroscopy, arthrocentesis, discoplasty and discectomy have all been reported to have reasonably good success; with reduction in signs and symptoms in the range of 80% to 90%.
    • Surgical success is highest with the first surgery and each surgical procedure reduces the success rate.
    • Surgical failure is often caused by lack of control of causal factors such as joint overload.
    • When surgery is indicated, the least invasive approach is recommended.

    Arthroscopy and Arthrocentesis

    These procedures will usually take place under general anesthetic, usually as a day case, and can adequately deal with most cases that present with pain and restricted mouth opening. Most patients have disease in the upper joint space which is amenable to access with an arthroscope or arthrocentesis, and improves pain and mouth opening in over 80% of cases[9]. Both clearly have been shown to be useful procedures with low morbidity that can considerably improve patients’ reported pain and mouth opening. It is often the first line treatment when non-surgical measures have failed, unless an open procedure is deemed appropriate.

    Al-Moraissi et al in a meta-analysis and systematic review of arthroscopy and arthrocentesis suggested that arthroscopy yielded better results than arthrocentesis[10].

    Arthrocentesis requires less surgical skill but does not permit direct visualization or removal of pathologic tissue. Patients with symptoms of limited mouth opening for greater than three months often have intra-articular adhesions, and arthrocentesis is not as effective as arthroscopy, which permits removal of these adhesions6.

    Early vs Late Surgical Intervention

    Arthroscopic surgery should be considered early in the management of patients with inflammatory/degenerative TMJ disease[11].  Israel reviewed forty-four consecutive patients who met the criteria for operative arthroscopy. Patients were divided into early and late intervention groups. The time between the onset of symptoms and undertaking arthroscopy was used to determine entry into the early versus late intervention group. An average of 5.4 and 33 months was the time between onset of symptoms and treatment in the two groups. All groups were evaluated for changes in preoperative versus postoperative pain levels based on visual analog scale (VAS) scores and maximum inter-incisal opening distance. The early intervention group had better surgical outcomes than the late intervention group with an increased difference in the pain VAS scores and inter-incisal opening.  Arthroscopic surgery should be considered early in the management of patients with inflammatory/degenerative TMJ disease.

    How Successful is Arthroscopic Surgery?

    McCain publish a six-year multicentre study of 4831 joints that underwent arthroscopic surgery: 91.6% had excellent or good motion, 91.3% had good or excellent pain reduction, 90.6% had good or excellent ability to maintain a normal diet, and 92% had good or excellent reduction in disability. This is the largest study to date and similar results have been published since then. Arthroscopy is a safe, effective, and minimally invasive method for treating intra-articular pathology[12].

    Further Advantages of Arthroscopic Surgery:

    The ability to visualised and operate within the joint space is by far the major advantage of arthroscopy as evidence by this video: Arthroscopic Discopexy 


    Arthroscopic discopexy

    Suture Needle Through TMJ Articular Disc

    Recurrent dislocation of the TMJ can also be managed by injection of the upper joint space and surrounding tissues with autologous blood or a sclerosing agent via an arthroscope. Reduction of the eminence has been described arthroscopically together with induction of retrodiscal fibrosis using a laser[13].

    Open Joint Procedures

    The need for open operations has decreased with increased use of arthroscopy; however, indications still exist. Arthroscopy can adequately treat most patients that present with pain and restriction. However, there are certain patients were an open procedure is more feasible in the long term.

    Open Surgery for Internal Derangement and Osteoarthritis

    Discectomy is indicated for a grossly deformed disc or where there is a central perforation as the avascular disc is unable to heal. The disc is usually removed through an open joint approach, although it can be done arthroscopically with retrodiscal scarification and anterior release. The use of an interpositional graft is debatable, with evidence both for and against its use in terms of long-term benefit[14].  A hemiarthoplasty can also be considered, but the evidence supporting its benefit opposed to discectomy alone is limited and the patients may ultimately require a joint replacement because of condylar erosion when symptoms recur as the joint fails.

    Eminoplasty can be done when there is a prominent lateral eminence and evidence of lateral impingement syndrome[15]. Eminoplasty decompresses the joint space. As the eminence is not an extra-articular structure, eminoplasty can be done arthroscopically

    The use of bone anchors has been employed for many decades with variable results. Although controversial and being a procedure based on limited evidence, there is no evidence to suggest that it is ineffective. Opposition to its use is based on clinical preference and influenced by the ability to perform it or not[16].   The current evidence is based on reports of case series. The largest to date is of 105 patients by Mehra and Wolford demonstrating that the use of a Mitek® anchor significantly reduced pain and TMJ dysfunction in patients without previous surgery to the TMJ[17].

    Condylar hyperplasia

    This can be managed with a high condylar shave to stop facial asymmetry from evolving after diagnosis. Condylar hyperplasia is a clinical diagnosis by which the growth of the mandible/condyle complex is documented over time. Bone scans ban be inaccurate and should only be used as an adjunct. 

    Arthroscopy versus Open Surgery in ID and OA

    Open procedures for ID is a well-established treatment for patients who fail to respond to conservative treatment. Ideally, all patients who are surgical candidates should have a step wise treatment ladder starting with arthroscopic surgery. However, it would be more advantageous to identify those patients whom arthroscopic surgery would be of limited value in the long term. There are no standardised protocols for whom primary open surgery would benefit. A few authors suggest that higher Wilkes staging has less chance of improvement with arthroscopy[18].

    Total Joint Replacement with TMJ Concepts Prosthesis

    TMJ Concepts (Ventura, Ca, USA) manufactures a patient-fitted prosthesis for the reconstruction of the temporomandibular joint. Each prosthesis is individually fabricated for the unique anatomy of the patient. This is based on CT imaging and utilizes computer aided design and manufacturing. Precise implant components allow excellent adaptation, fixation and optimum function. All materials utilized for manufacturing (titanium, cobalt-chromium-molybdenum, and ultra-high-molecular-weight polyethylene) have several decades of successful clinical use in reconstruction of hip and knee prosthesis.DEVICE HISTORY
    TMJ Concepts (Ventura, CA) began manufacturing these implants under an FDA premarket notification in December 1997. Prior to this time, these implants were manufactured by Techmedica, Inc. from January 1989 to September 1993.

    A premarket approval [PMA] application was submitted on January 6, 1999. This PMA received FDA approval on July 2, 1999, allowing TMJ Concepts to continue providing these implants for TMJ patients.
    These devices have been successfully placed in patients for over twenty-five years. This is an FDA approved device.

    This is the only treatment that has been scientifically validated for end stage TMJ disease with high success rates over the long term. 


[1] Murakami K, Kaneshita S, Kanoh C, et al. Ten-year outcome of nonsurgical treatment for internal derangement

of the temporomandibular joint with closed lock. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94(5):572–5.

[2] Minakuchi H, Kuboki T, Matsuka Y, et al. Randomized controlled evaluation of non-surgical treatments for temporomandibular joint anterior disk displacement without reduction. J Dent Res 2001;80(3): 924–8.

[3] Lundh H, Westesson PL, Eriksson L, et al. Temporomandibular joint disk displacement without reduction. Treatment with flat occlusal splint versus no treatment. Oral Surg Oral Med Oral Pathol 1992; 73(6):655–8.

[4] Truelove E, Huggins KH, Mancl L, et al. The efficacy of traditional, low-cost and non-splint therapies for temporomandibular disorders: a randomized controlled trial. J Am Dent Assoc 2006;137(8): 1099–107.

[5] Clark G, Minakuchi H. Oral appliances. In: Laskin DM, Greene CS, Hylander WL, editors. Temporomandibular disorders: an evidenced based approach to diagnosis & treatment. Quintessence Publishing; 2006. p. 377–90.

[6] Scrivani SJ, Keith, Kaban LB. Temporomandibular disorders. N Engl J Med 2008;359:2693–705.

[7] 5. Randolph CS, Greene CS, Moretti R, et al: Conservative management of temporomandibular disorders: A post treatment comparison between patients from a university clinic and from private practice. Am J Orthod Dentofacial Orthop 98:77, 1990

[8] Yan YB, Liang SX, Shen J, et al. Current concepts in the pathogenesis of traumatic temporomandibular joint ankylosis. Head Face Med2014;10:35.33.

[9] Review Current thinking about the management of dysfunction of the temporomandibular joint: a reviews. Rajapakse, N. Ahmed, A.J. Sidebottom. British Journal of Oral and Maxillofacial Surgery 55 (2017) 351–356 2017

[10] Al-Moraissi EA. Arthroscopy versus arthrocentesis in the management of internal derangement of the temporomandibular joint: a systematic review and meta-analysis. Int J Oral Maxillofac Surg 2015; 44(4):104–12.

[11] Israel, Behrman, Friedman, Silberstein. J Oral Maxillofac Surg 68:2661-2667, 2010

[12]McCain JP1Sanders BKoslin MGQuinn JHPeters PBIndresano AT. Temporomandibular joint arthroscopy: a 6-year multicenter retrospective study of 4,831 joints. J Oral Maxillofac Surg. 1992 Sep;50(9):926-30.

[13] Ybema A, De Bont L, Spijkervet F. Arthroscopic cauterization of retrodiscal tissue as a successful minimal invasive therapy in habitual temporomandibular joint luxation. Int J Oral Maxillofac Surg2013;42:376–9.38.

[14] Dimitroulis G. The use of dermis grafts after discectomy for internal derangement of the temporomandibular joint. J Oral Maxillofac Surg 2005;63:173–8.39.

[15] W. S. Kirk Jr.: Lateral impingements of the temporomandibular joint: a classification system and MRI imaging characteristics. Int. J. Oral Maxillofac. Surg. 2013; 42: 223–228.

[16] Gonclaves et al, Does Disc Repositioning really work? Oral Maxillofacial Surg Clinics N America p85-107, 2015

[17] P Mehra L Wolford IJOMS 2001 30 497 - 503

[18] TzanidakisSidebottom AJ  Outcomes of open temporomandibular joint surgery following failure to improve after arthroscopy: is there an algorithm for success? Br J Oral Maxillofac Surg. 2013 Dec;51(8):818-21. doi: 10.1016/j.bjoms.2013.04.013. Epub 2013 May 20.