Temporomandibular joint involvement in rheumatoid arthritis; clinical, tomographic and magnetic resonance imaging study, a new MRI scoring system

ABSTRACT

The primary objective of this study was to create a new MRI scoring system for assessment of tembromandibular joints [TMJs] arthritic changes in rheumatoid arthritis [RA] based on the precise TMJ tomographic scoring system adopted in 2004[1]. The second aim was to assess the correlation and compare the sensitivity between the new MRI scoring system and the previously established tomographic one. Finally was to correlate the TMJ image findings with the RA clinical disease activity score and disease duration. Twenty RA patients represented forty TMJs were included in the study and recruited from the Rheumatology and Rehabilitation department, Cairo University Hospitals. Full history taking and thorough rheumatologic and intra oral clinical examination were carried out. The patients' disease activity score with three variables [DAS-3]; the Ritchie articular index [RAI], swollen joint count [0-44] and ESR, was recorded. Bilateral TMJ conventional tomography and MRI were done to all patients. Anew MRI scoring system for the severity of TMJ arthritic changes was created based on the TMJ tomographic scoring system[1]. This newly scoring system termed as RA-TMJ-MRI-S states for Rheumatoid Arthritis in TMJ by Magnetic Resonance Imaging Score. The new RA-TMJ-MRI-S not only showed a very high statistical correlation to tomographic scoring system [p = 0.0000] but also demonstrated a respectable sensitivity in early detection of the arthritic changes in TMJ. There was no correlation between the MRI or tomography findings and the DAS-3 or the disease duration. It is recommended to use the new RA-TMJ-MRI-S system; the first MRI scoring system of TMJ that was proved to be superior to the tomographic scoring system, when proper assessment and follow up of the TMJ in RA patients are needed