[Relationship between condyle movement and disc position in patients with Class II division 1 malocclusion]

To investigate the relationship between condyle movement and temporomandibular disorders (TMD) in patients with Class II division 1 malocclusion.Twenty patients (from 11 to 12 years old) with Class II division 1 malocclusion before treatment were collected. Computer aided diagnosis axiograph (CADIAX) and magnetic resonance images (MRI) were used to analyze the condyle movement between disc displacement and normal groups.The sensitive values were found in open/close process in patients with disc displacement: Y [Left: (0.32 +/- 0.10) mm, Right: (-0.91 +/- 0.49) mm ], Z [Left: (4.20 +/- 0.70) mm, Right: (3.44 +/- 0.21) mm], sagittal condylar inclination (SCI) [Left: (32.48 +/- 7.70) degrees , Right: (33.47 +/- 12.60) degrees ] and horizontal condylar inclination (TCI) [Left: (-2.60 +/- 2.02) degrees , R: (-9.23 +/- 5.58) degrees ], and those items showed significant difference between two groups.The side shift of condyle movement in maximum open/close process might be the inducement of disc displacement. It was revealed that the changes in condyle movement could give useful information in early stage of functional treatment.