PURPOSE: To assess the relationship between mandibular asymmetry and d
isorders of the temporomandibular joint. METHODS: We used advanced ima
ging of the temporomandibular joint to distinguish different causes of
mandibular asymmetry. MR imaging and arthrography were applied to the
temporomandibular joints of 11 patients presenting with mandibular as
ymmetry. RESULTS: Condyle hyperplasia was identified as the cause of t
he asymmetry in 5 patients. In the other 6 patients the mandibular con
dyle was normal on the long side, but the short side of the face demon
strated a small condyle head, short condyle neck associated with disk
displacement, internal derangement, and degenerative joint disease of
the temporomandibular joint. CONCLUSIONS: These observations suggest t
hat both condyle hyperplasia on the long side of the mandible and disk
displacement and degenerative joint disease of the temporomandibular
joint on the short side can cause mandibular asymmetry. It was conclud
ed that MR imaging or arthrography can be valuable for understanding t
he cause of mandibular asymmetry and be effective in treatment plannin
g.