A Biomechanical Study of the Human Facial Skeleton by Means of Strain-Sensitive Lacquer

Abstract

For the purpose of clarifying the orientation of the principal strains on the surface of the human facial skeleton produced by the masticatory action, an experiment was made by means of strain sensitive lacquer DILAR-B applied to macerated skulls which were subjected to a static condition approximated to that of the masticatory action. The results obtained are shown in Figs. 4 and 6 along with the results obtained from the experiment by means of wire strain gauge illustrated in Fig. 5. Rows of parallely arranged cracks showing the orientations of axes of principal strain appeared as follows : from the alveolus of the loaded tooth radiately upwards (compression); along the maxillozygomatic crest (compression); from the originating area of the masseter to medial part of the infraorbital region (tension); from the originating area of the masseter to the lateral part of the frontal process of the zygomatic bone (tension); on the nasal root roughly longitudinally (compression); in the supraorbital region obliquely (tension). There could be found no marked contradiction between both kinds of the results with respect to the rough orientation of the axes of principal strains distributed in the facial skeleton due to the masticatory action. © 1966, Editorial Board of Okajimas Folia Anatomica Japonica. All rights reserved.