The role of ultrasonography in the diagnosis of temporomandibular joint disc displacement and intrarticular effusion

The aim of this work is to conduct a preliminary study to investigate the
usefulness of ultrasonography (US) in the study of temporomandibular joint (TMJ),
comparing ultrasonographic diagnosis of joint effusion and disc displacement with
those based on an accurate clinical examination. METHODS: Participants in this
study were 47 consecutive patients complaining for TMJ problems. All 94 TMJs were
evaluated to detect the presence of intra-articular effusion and disc
displacement by means of 2 diagnostic instruments: a standardized clinical
assessment based on the Research Diagnostic Criteria for Temporomandibular
Disorders (RDC-TMD) at the Section of Prosthetic Dentistry, and an
ultrasonographic investigation conducted by a blinded operator at the Operative
Unit of the Department of Rheumatology, Univesity of Pisa, Italy. Agreement
between the two diagnostic techniques has been evaluated by means of Cohen's K
test. RESULTS: Ultrasonography showed a good agreement with clinical assessment
for the diagnosis of both intra-articular effusion (percentage of agreement 80%;
K=0.611) and disc displacement (agreement 81.9%; K=0.572). CONCLUSION: When
compared to a standardized clinical assessment, ultrasonographic technique showed
a good diagnostic capability to detect TMJ intra-articular effusion and disc
displacement. Within all the limitations of this study, it can be suggested that
ultrasonography could represent a promising imaging technique in the study of
temporomandibular joint.