Application of a geometric principle for locating the mandibular hinge axis through the use of a double recording stylus

The hinge axis of the mandible has been determined by using double recording styli at a distance of 2 to 4 inches from the estimated axis area. Visible arcs in pairs on a plain recording surface become the basis for a geometric construction by which the true axis of rotation can be identified. The theoretical basis for this method of axis location is sound and practical as applied and the clinical results indicate that the procedure is accurate.