Condylar bony change and craniofacial morphology in orthodontic patients with temporomandibular disorders (TMD) symptoms: a pilot study using helical computed tomography and magnetic resonance imaging.
OBJECTIVE
To investigate how condylar bony changes relate to craniofacial morphology using helical CT and MRI.


METHODS
Craniofacial morphology of orthodontic patients with condylar bony changes was compared with Japanese standard.


METHODS
The Department of Orthodontics, Niigata University School of Dentistry, Twenty-nine subjects were selected from orthodontic patients (six males and 23 females, a mean age of 18.8 +/- 6.3 years) who were diagnosed by helical CT as having condylar bony changes.


METHODS
Subjects were divided into two groups: a unilateral condylar bony change group (unilateral group) (four males and nine females) and a bilateral condylar bony change group (bilateral group) (two males and 14 females).


METHODS
Condylar bony changes were evaluated on reconstructed coronal and sagittal CT scans. Disk positions were evaluated by MRI scans. Five linear and four angular measurements in lateral and posteroanterior cephalograms were compared with those of an age- and sex-matched 'standard population' from the Japanese standard.


RESULTS
In the bilateral group, osteophyte formation and erosion were the common bony changes and were present in adult as well as juvenile subjects. In the unilateral group, flattening was the most common features and erosion was only present in subjects below 19 years. Disk displacement without reduction was seen in 90.6% of the bilateral group, and in 76.9% of the unilateral group. Retrognathic mandibles were shown in the bilateral group. All subjects exhibited a lateral shift of the menton toward the condylar bony changed side in the unilateral group.


CONCLUSIONS
Condylar bony changes might be progressive and unstable in adults of the bilateral group as well as in juveniles of the both groups. It appears that condylar bony changes may be related to a lateral shift of the mandible and a retrognathic mandible in orthodontic patients with TMD symptoms.
Yamada
K
K
Department of Orthodontics, Niigata University School of Dentistry, Japan. kazuhiro@dent.niigata-u.ac.jp
Hiruma
Y
Y
Hanada
K
K
Hayashi
T
T
Koyama
J
J
Ito
J
J
D000293:Adolescent; D000328:Adult; D002508:Cephalometry; D002648:Child; D005146:Facial Asymmetry / Q000175:diagnosis / Q000209:etiology*; D005147:Facial Bones / Q000473:pathology; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000175:diagnosis / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008334:Mandible / Q000254:growth & development / Q000503:physiopathology*; D008335:Mandibular Condyle / Q000473:pathology*; D010865:Pilot Projects; D063173:Retrognathia / Q000209:etiology; D019224:Temporomandibular Joint Disc / Q000473:pathology; D013705:Temporomandibular Joint Disorders / Q000150:complications* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods