It is very important for the ideal restorations of anterior openbite patients to record the mandibular movement and to harmonize mandibular movement with other organs is stomatognathic systems. This study was designed to compare the mandibular movement of anterior openbite patients with that of normal bite(Angle Class I) patients, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Saphon visi-trainer Model 3(Tokyo Shizisha Co. Japan) and Denar Pantronic (Denar Corp., U.S.A) were used to record mandibular movement. Pantronic survey was performed by using an arbitrary hinge axis according to
manufacturer’s direction. Twenty-eight adult who have physiologically normal occlusion(Angle Class I) and are free of TM dysfunction were selected as a control group(Group 1). Fifteen adult who are anterior openbite patient and have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). @ES The results are as follows: @EN 1. There was no statistically significant difference between the average immediate and progressive side shift of anterior openbite patients(0.54mm, 7.57°)and those of normal group(0.49mm, 5.96°). 2. The average protrusive and orbiting condylar inclination of anterior openbite patient(30.87°,32.27)were significantly lower than those of normal group(36.11°,39.04°)(P<0.05). 3. In the results of Visi-trainer recordings, the mean for the maximum protrusion, the maximum laterotruion, the angle of laterotrusion and the angle of protrusion in the horizontal trajectory between group 1 and 2 did not differ significantly. 4. The mean for the angle of protrusion, the maximum opening in the frontal trajectory, the ICP-RCP(A-P) distance and the angle of protrusion in the sagittal trajectory differ significantly p<0.05). 5. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.
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