TMJ Disc Displacements

Original Editor - Andrea Reineke

Top Contributors - Abbey Wright, Lynda Chukwu, Kim Jackson, Andrea Reineke and George Prudden  

Introduction

Temperomandibular joint displacement, also known as internal disc derangement, is an abnormal relationship between the articular disc, the mandibular condyle and the mandibular fossa[1]. The most frequent displacement of the disc is anterior to the mandibular condyle however, in rare cases it can be posteriorly. The prognosis for these conditions is good and normally recover with minimal intervention or conservative management.[1]
Limited TMJ opening[2]
Imaging studies have demonstrated that a more anterior disc position is relatively common in the asymptomatic population.[3] It is also thought that in the majority of people the TMJ adapts to the disc position and rarely produces pain from being in a different position. [4]

Clinically Relevant Anatomy

See TMJ anatomy

Clinical Presentation

Symptoms

  • Pain or discomfort associated with anyone or combination of: chewing, yawning, talking, bruxism[5]
  • Headaches
  • Ear pain
  • TMJ range of movement may be restricted
  • Crepitus/clicking during movement of the jaw
  • Pain or discomfort can be acute or chronic that can fluctuate in intensity.
  • Emotional issues such as depression is commonly associated with TMJ pain

Duration of symptoms may vary from hours to days.

Red flags

  1. Neurological signs
  2. Swelling
  3. Nose bleeding
  4. Dysphagia or dysarthria
  5. Unexplained weight loss
  6. Auditory complaints
  7. Constant pain unrelated to jaw movement

Types of TMJ disc displacement

[6]
  1. Disc displacement with reduction (DDWR)[1][7]: The articular disc displaces anteriorly to the condylar head, when the mouth is opened the disc relocates on the the condylar head.
    • Hearing and palpating joint noises during opening and closing
    • Protrusive opening and closings stops the reciprocal click
    • There is unlikely to be any restriction in ROM due to the disc relocating when the mouth opens
  2. Disc displacement with reduction with intermittent locking[1][7]: identical to DDWR with the additional symptom of intermittent limited jaw opening. This occurs when the disc does not reduce.
  3. Disc displacement without reduction (DDwoR) with limited opening:[1][8] the articular disc displaces but does not reduce.
    • TMJ pain
    • Limited jaw range of movement <40mm
    • Clicking and popping 4. Disc displacement without reduction without limited opening: identical to DDwoR without limited ROM, although limited ROM must have occurred at some point.

These stages are under review and a new classification system is being trialled however at present it has only been trialled in adolescents.[9] This classification reports five stages of disc displacement based on MRI results.

Yang’s Classification of Juvenile TMJ Anterior Disc Displacement

stage Disc Condyle Marrow
Stage 0 Basic shape Normal condylar shape and height Normal volume and quality
Stage 1 Basic shape Mild and local condylar resorption, but normal condylar height Partially reduced on the top
Stage 2 Basic shape Moderate condylar resorption, reduced condylar height. Mildly reduced
Stage 3 Basic shape or distorted Severe condylar resorption Moderately reduced
3A Basic shape remains, or mildly distorted and shortened Small, but basic shape is present Moderately reduced
3B Severely distorted and shortened Small, but basic shape is present Moderately reduced
Stage 4 Basic shape or distorted Severe condylar resorption Moderately reduced with inflammatory changes, or severe reduced, or absent
4A Basic shape remains or distorted. Perforation is common Severe resorption, loss of integrity of cortical bone. Moderately reduced with severe inflammatory changes
4B Basic shape remains or distorted. Perforation is common Severe resorption, or complete resorption Severe reduced, or absent

[9]

Diagnostic Procedures

Assessment of disc displacement can be done via subjective assessment, objective assessment and radiography.[10]

Subjective assessment

The patient may have the history of:

  • Insidious or traumatic onset
  • Difficulty chewing food
  • Reduced mouth opening
  • Subjective clicking and popping

Objective Assessment

  • Pain on TMJ palpation[11]
  • Potential clicking on jaw opening
  • Reduced TMJ range of movement
  • Associated muscular tightness of cervical and facial muscles such as sternocleidomastoid, upper trapezius and masseter.

Radiography

  • XR[12]
  • Ultrasound can be useful in assessing the extent of disc derangement
  • MRI is considered gold standard

Management/Intervention

Disc displacement without reduction

The best treatment plan for disc displacement without reduction is still under discussion and requires more evidence as treatment is usually based on experience rather than evidence.[13][8]

Interventions can range from conservative management to surgical intervention. Although primary management for disc displacement should always be conservative.[14]

Conservative management (primarily physiotherapy)

  1. Education and self-management[8]
  2. Splinting
  3. Therapeutic exercise
  4. Joint mobilisation of the TMJ and cervical spine
  5. Active jaw exercises and strengthening
  6. Cognitive behavioural therapy
  7. NSAIDs and analgesia

Surgical intervention

  1. Arthrocentesis[15]
  2. Arthroscopy
  3. Open joint intervenetion

On analysis of the surgical interventions there was no change in outcomes (pain and TMJ range of movement) when compared with each other. [8]

Clinical bottom line

Regardless of intervention disc displacement without reduction has shown to improve over time, therefore the optimum treatment would be the least invasive and most cost effective i.e. education, self-management and early TMJ manipulation.[8] In some extreme cases surgical intervention may be required but should be treated as a last choice.

Differential Diagnosis

References

  1. 1.0 1.1 1.2 1.3 1.4 Young AL. Internal derangements of the temporomandibular joint: A review of the anatomy, diagnosis, and management. The Journal of the Indian Prosthodontic Society. 2015 Jan;15(1):2.
  2. Wright EF, North SL. Management and treatment of temporomandibular disorders: a clinical perspective. Journal of Manual & Manipulative Therapy. 2009 Dec 1;17(4):247-54.
  3. Kircos LT, Ortendahl DA, Mark AS, Arakawa M. Magnetic resonance imaging of the TMJ disc in asymptomatic volunteers. Journal of oral and maxillofacial surgery. 1987 Oct 1;45(10):852-4.
  4. Poluha RL, Canales GD, Costa YM, Grossmann E, Bonjardim LR, Conti PC. Temporomandibular joint disc displacement with reduction: a review of mechanisms and clinical presentation. Journal of Applied Oral Science. 2019;27.
  5. Canales GD, Guarda-Nardini L, Rizzatti-Barbosa CM, Conti PC, Manfredini D. Distribution of depression, somatization and pain-related impairment in patients with chronic temporomandibular disorders. Journal of Applied Oral Science. 2019;27.
  6. The Dentist! TMJ disc displacement. Available from: https://www.youtube.com/watch?v=IHl6WNeSXIk [last accessed: 11/8/2017]
  7. 7.0 7.1 Schiffman E, Ohrbach R, Truelove E, Look J, Anderson G, Goulet JP, List T, Svensson P. Diagnostic criteria for temporomandibular disorders (DC/TMD) for clinical and research applications: recommendations of the International RDC/TMD Consortium Network and Orofacial Pain Special Interest Group. Journal of oral & facial pain and headache. 2014;28(1):6.
  8. 8.0 8.1 8.2 8.3 8.4 Al-Baghdadi M, Durham J, Araujo-Soares V, Robalino S, Errington L, Steele J. TMJ disc displacement without reduction management: a systematic review. Journal of dental research. 2014 Jul;93(7_suppl):37S-51S.
  9. 9.0 9.1 Shen P, Xie Q, Ma Z, Abdelrehem A, Zhang S, Yang C. Yang’s Classification of Juvenile TMJ Anterior Disc Displacement Contributing to Treatment protocols. Scientific reports. 2019 Apr 4;9(1):1-8.
  10. 10.0 10.1 Wright EF, North SL. Management and treatment of temporomandibular disorders: a clinical perspective. Journal of Manual & Manipulative Therapy. 2009 Dec 1;17(4):247-54.
  11. Ali HM. Diagnostic Criteria for Temporomandibular joint Disorders: A physiotherapist's perspective. Physiotherapy. 2002 Jul 1;88(7):421-6.
  12. Razek AA, Al Belasy FA, Ahmed WM, Haggag MA. Assessment of articular disc displacement of temporomandibular joint with ultrasound. Journal of ultrasound. 2015 Jun 1;18(2):159-63.
  13. Haketa T, Kino K, Sugisaki M, Takaoka M, Ohta T. Randomized clinical trial of treatment for TMJ disc displacement. Journal of dental research. 2010 Nov;89(11):1259-63.
  14. Schiffman EL, Look JO, Hodges JS, Swift JQ, Decker KL, Hathaway KM, Templeton RB, Fricton JR. Randomized effectiveness study of four therapeutic strategies for TMJ closed lock. Journal of dental research. 2007 Jan;86(1):58-63.
  15. Monje-Gil F, Nitzan D, González-Garcia R. Temporomandibular joint arthrocentesis. Review of the literature. Medicina oral, patologia oral y cirugia bucal. 2012 Jul;17(4):e575.