An Investigation of Enamel Thickness in Human Lower Incisor Teeth

¹ Eastman Dental Dispensary, Rochester, New York

A technique has been described for the reproduction of any plane of section in any tooth, or any object, by the use of semiserial sections and a graphical reconstruction technique. This technique was applied to a study of enamel thickness distribution in a pooled sample of 27 lower incisor teeth. A graphical method was used to show that, while correlation between tooth size and enamel thickness was slight, there was a definite pattern of enamel distribution. For the incisal two-thirds of the tooth, the buccal enamel was thickest, followed in turn by the distal, mesial, and lingual enamel. The rate of change of enamel thickness from gingival to incisal was quite different for the buccal, proximal, and lingual surfaces.

This technique is equally applicable in investigations of the distribution through teeth of other anatomical characteristics of enamel, such as tufts, lamellae, striae, pigments, optical and radio density, prism orientation, and the spread of dental caries and of physical properties, such as enamel volume, thickness, and surface curvature. The tracings and reconstructions provide an ideal source of data for the study of tooth size and morphology. The technique has already been used in a detailed study of enamel thickness at the base of pits and fissures, since it permitted visualization of an irregular plane of section along the fissure area.¹² A modification of the tracing technique can be used to make accurate large-scale models of teeth and mirror images of such models (i.e., left and right teeth from the one original tooth) for display or teaching purposes.

The technique could be equally well applied to other serial or semiserial sections for reconstruction of various section planes or determination of the three-dimensional configuration of the anatomical features in such structures as cells, blood vessels, and bones.