Abstract
The range of jaw movements at the incisor point was recorded and analyzed three dimensionally. It was found, as the result, that 1) the range of movements was shown as a rhomboidal figure, and the angle of Gothic arch in the horizontal plane was approximately 120 degrees from the centric occlusion to the vertical dimension of 20 mm, 2) the posterior border opening and closing pathways were present a little forward to the apex of Gothic arch, and 3) the hinge movement was impossible in few cases.