A Study of the Relationship of the Dental Arch to its Supporting Structure

Abstract

Using 19 human caucasian skulls, a radiographic technique was developed to study the relationship of the dental arch to its supporting structure. All skulls were oriented to occlusal plane and x-rayed from a distance of five feet. The highest positive linear correlation recorded was between mandibular second molar width and apical base width in the second molar region. In the maxillary arch, high correlations were found to exist in both the cuspid and molar regions between dental arch width and apical base width. Correlations were lacking in the mandibular cuspid region between dental width and apical base width and between maxillary and mandibular dental and apical base depth. The central tendency and dispersion was calculated, as well as the standard error of the mean and coefficient of variation for all groups of measurements which included arch widths, apical base widths, arch depths and apical base depths. A generalized description of the position of the dentition to its supporting structure was presented; this indicated that the buccal segments in most cases showed less variation in their position over their supporting structure than the anterior segments. Each dental arch was descriptively classified using the terms ovoid, square, tapering and combinations of these.