[Analysis of human petrous bone for the purpose of measurements and observations of the course of collagen in polarized light].

Abstract

The values of the superior angle, height and cross sections of the petrous bone show a considerable variation which seems to be almost independent of the form and size of the skull. The cross section of the bone resembles more the positive part of a sinus curve than a triangle. The theoretical superior angle calculated by using cross section and height has a mean value of 87 degrees +/- 6 degrees. The values of height and cross sections are correlated in non-linear equation curve, the formula of which can be calculated as y = 0,59 x2 + 105,3. The values of height and the superior angle have a negative correlation and follow a tangent function. The values of the superior angle correlated to the cross section area as far as they belong to the same height also follow a tangent function. The angle between the plane of the greatest height of the petrous prism and the occlusal surface shows a mean of 32 degrees. The alignment of the collagen fibers analyzed by polarized light indicates a bending stress of the petrous bone. The histological findings and the simple correlations of the measured values suggest that form and structure of the petrous bone is adjusted by biomechanical factors.