Related Experiment Video
Updated: Jul 4, 2026
A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle
Published on: January 11, 2018
Muscular and condylar response to rapid maxillary expansion. Part 3: magnetic resonance assessment of condyle-disc
F Emel Arat1, Z Mirzen Arat, Bryan Tompson
1Department of Orthodontics, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada. femelarat@yahoo.com
Introduction:
The aim of this prospective study was to assess temporomandibular joint (TMJ) condyle-disc positions at the sagittal and coronal planes of magnetic resonance images (MRIs) before and after rapid maxillary expansion (RME).
Methods:
The study included 18 subjects (11 girls, 7 boys) with a mean age of 12.54 years with unilateral or bilateral posterior crossbite that included at least 3 posterior teeth. The clinical and radiographic assessments of the TMJ were done before (T1) and 18 weeks after (T2) RME. A Haas-type expansion appliance was used for an average treatment time of 3.5 weeks.
Results:
A visual MRI analysis of pretreatment condyle-disc positions showed that 8 TMJs had medial disc displacement, 3 had anteromedial disc displacement, and 2 had lateral disc displacement. The disc positions remained unchanged at T2 except in 1 subject, who developed unilateral anterior disc displacement. Unilateral joint sounds developed in 3 subjects without changes in the disc positions.
Conclusions:
Posterior crossbite can be considered a minor risk factor for temporomandibular disorder (TMD). RME is neither a risk factor nor a prevention for TMD. Coronal MRIs contribute complementary information for optimal diagnosis of TMD.
