Magnetic resonance images of the temporomandibular joints of patients with acquired open bite.
OBJECTIVE
Acquired anterior open bites were reported as the consequence of condylar collapse, which was associated with inflammatory TMJ disorders. However, we have seen such malocclusion patients whose condylar changes seemed to be related to TMJ degeneration associated with internal derangement. The aims of this study were to review the clinical history and to study the TMJ MRI of these patients.


METHODS
TMJ MRIs of patients, who had presented acquired anterior open bite at first visit, were retrieved from the image database for the analysis. Clinical histories focused on internal derangement were collected retrospectively. The soft tissue and hard tissue changes disclosed by MRI were also studied.


RESULTS
All patients had experienced common signs/symptoms of TMJ internal derangement. All affected TMJs had anteriorly displaced disks and degenerative changes. Horizontally destructed condylar forms were seen significantly more frequently in these patients.


CONCLUSIONS
TMJ degeneration associated with displaced disks might be a cause leading to the development of acquired anterior open bite.
Chen
Yunn-Jy
YJ
School of Dentistry, National Taiwan University, Medical College and Hospital, Taipei, Taiwan. chenyj@ha.mc.ntu.edu.tw <chenyj@ha.mc.ntu.edu.tw>
Shih
Tiffany Ting-Fang
TT
Wang
Juo-Song
JS
Wang
Huey-Yuan
HY
Shiau
Yuh-Yuan
YY
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000150:complications / Q000473:pathology; D008279:Magnetic Resonance Imaging; D017090:Occlusal Splints; D024343:Open Bite / Q000209:etiology* / Q000473:pathology; D010003:Osteoarthritis / Q000150:complications* / Q000473:pathology; D012189:Retrospective Studies; D013704:Temporomandibular Joint / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000150:complications* / Q000473:pathology