Abstract:

Objective To investigate the relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement (TMJID).Methods Oblique sagittal Tl weighted MR imaging at closed and open mouth and Oblique sagittal 12 weighted MR imaging at closed mouth were obtained from 88 joints of 44 patients suffering from TMD. Condylar marrow signal abnormalities were reviewed and classified into bone marrow edema pattern (hypo intense T1，hyperintense 712)，sclerosis pattern (hypointense TI and hypointense 12) and combined edema and sclerosis pattern. Results Of 88) joints，13(14.8%) joints showed condylar marrow signal abnormalities , among which II belonged to edema pattern and, 1 was sclerosis pattern and the other was the combined pattern. Of 13 joints with condylar marrow signal abnormalities, 11(84.6%)had TMJID. Of 75 joints with normal marrow signal, 25(33.3%)joints had TMJID. There was significant correlation between condylar marrow signal ab- normalities and TMJID(P<0.05).Condusion Disc displacement is one of the factors inducing condylar marrow signal abnormalities. The pathological process from disc displacement to osteonecrosis requires further study.

Key words: temporomandibularjointinternalderangement, condylarmarrowsignalabnormalities, magneticresonanceimaging,