Analysis of the enamel hypoplasia using micro-CT scanner versus classical method

Abstract

This article demonstrates the use of micro-CT scanning of the teeth surface for recognizing and evaluating severity of the enamel hypoplasia. To test capabilities of the microtomography versus classical method of evaluation hypoplastic defects of the enamel we selected two human teeth (C, M(2)) showing different types of enamel hypoplasia: linear, pits, and groove. Examined samples derive from archeological material dated on XVII-XVIII AD and excavated in Poland. In the current study we proved that micro-CT scanning is a powerful technique not only for imaging all kinds of the enamel hypoplasia but also allows to perform accurate measurements of the enamel defects. We figure out that contrary to the classical method of scoring enamel defects, the micro-computed tomography yields adequate data which serve for estimating the length of stress episode and length of interval between them.

Quantifying linear enamel hypoplasia in Virunga Mountain gorillas and other great apes

“…However, all qualitatively identified LEH defect depths fall completely outside the distribution of perikymata depths (Figure ). New research addresses the problem of defining normal vs. abnormal surface morphology on the basis of perikymata spacing via measuring microscope, SEM, and focus variation microscopy (Bocaege & Hillson, ; Bocaege et al ; King et al, ; Temple et al, 2013), and on the basis of depth using microCT scans (Marchewka et al, ), digital microscopy (Skinner & Pruetz, 2012), ) or a measuring microscope (Henriquez & Oxenham, ). A challenge with identifying wider‐than‐average perikymata is that even slight deviations from “normal” spacing are flagged as potential LEH defects (Bocaege & Hillson, ; Hassett ; Hillson, ).…”

“…However, variation in the internal geometry of underlying enamel growth increments may also influence defect depth (Guatelli‐Steinberg et al, ). While histological analysis is the only way to obtain a complete understanding of how individual defects formed (Witzel, Kierdorf, Schultz, & Kierdorf, ), nondestructive imaging‐based methods have been developed to quantitatively characterize defect morphology from the outer enamel surface (Bocaege & Hillson, ; Bocaege, Humphrey, & Hillson, ; Guatelli‐Steinberg, Larsen, & Hutchinson, ; Hassett, ; Henriquez & Oxenham, ; Hillson, ; Hillson & Jones, ; King, Hillson, & Humphrey, , Le Cabec, Tang, & Tafforeau, ; Marchewka, Skrzat, & Wróbel, ; Skinner & Pruetz, ; Skinner & Skinner, ; Temple, McGroarty, Guatelli‐Steinberg, Nakatsukasa, & Matsumura, ). These methods have the potential to reduce interobserver error in the identification and characterization of defects, but fundamental questions remain about the extent of inter‐ and intraspecific variation in defect morphology in primates.…”

“…LEH defect severity is commonly assessed either macroscopically or microscopically based on the width and/or depth of a given defect. It is assumed to reflect the duration and/or magnitude of the growth disruption (Duray, ; Guatelli‐Steinberg, ; Henriquez and Oxenham, ; Marchewka et al, ; Skinner & Pruetz, ; Skinner & Skinner, ). Researchers have used imaging techniques to measure the depth of individual defects using engineer's measuring microscopes, microCT (computed tomography), and digital microscopy in modern humans and chimpanzees (Henriquez & Oxenham, ; Marchewka et al, ; Skinner and Pruetz, ).…”

Micro‐CT Imaging and Analysis of Enamel Defects on the Early Late Pleistocene Xujiayao Juvenile

“…For LEHs, initial observations were performed using the binocular microscope and SEM. Then, on each micro‐CT‐reconstructed tooth, LEH defects were identified as bands on the full 3D reconstruction that could be matched to depressions on sagittal cross‐sections of the enamel surface (Marchewka et al, ) (Figure ).…”

“…The first is to systematically document and describe enamel defects in the Xujiayao juvenile as identified using binocular, scanning electron microscopy (SEM) and micro‐computed tomography (micro‐CT) imaging techniques. Recently, Marchewka et al () demonstrated that enamel defects that were not visible using SEM or light microscopy could be clearly identified using micro‐CT. Here, we evaluate differences among the three methods used to identify enamel defects.…”