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Updated: May 15, 2025

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
The temporomandibular joint disc: A complex fable about an elusive butterfly
Louis G Mercuri1, Charles S Greene2, Daniele Manfredini3
1Department of Orthopaedic Surgery, Rush University Medical Center, Chicago, IL, USA.
Introduction:
Discussions related to the diagnosis and management of temporomandibular joint (TMJ) disorders (TMDs) have always been interesting, and at times controversial, since they involve combinations of dental, medical, and surgical etiological theories and management strategies. Amongst the various recommendations that emerged over the years was that any dental and surgical procedures that are primarily focused on mandible repositioning and irreversible changes to dental occlusion should be avoided. This statement has important implications for appraising the validity of physiopathology concepts and treatment proposals centered around the evaluation of TMJ disc position, since they also generally lead to performing irreversible procedures.
Methods:
A review of the pertinent TMJ literature related to the articular disc position and its association with TMD symptoms was carried out by the authors.
Results:
For many practitioners, the position of the TMJ disc has been regarded as a primary cause of TMJ pain and dysfunction. For decades, incoordination between the TMJ disc, the condylar head and the articular eminence was indeed considered the main factor for the etiology of intracapsular TMD symptoms and consequently an important target for therapy. However, research has shown that synovitis is the more important variable in dealing with those conditions.
Conclusion:
In this commentary, the biological rationale to consider synovitis, rather than disc position, as the linchpin for clinical symptoms is presented in detail. Hopefully, this might contribute to putting the elusive butterfly characteristics of this topic finally to rest.
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