Testing the reliability of CT scan‐based dental wear magnitude scoring

Abstract

Objectives Digital models are now frequently used in biological anthropology (bioanthropology) research. Despite several studies validating this type of research, none has examined if the assessment of dental wear magnitude based on Computerized Tomography (CT) scans is reliable. Thus, this study aims to fill this gap and assess if dental wear magnitude scoring based on CT scans provides results consistent with scoring based on direct observation of the physical specimens. Materials and Methods Dental wear magnitude from 412 teeth of 35 mandibles originating from the Portuguese Muge and Sado Mesolithic shell‐middens was scored. The mandibles were also CT scanned and visualized using 3D Slicer. CT scan‐based scoring of dental wear magnitude was then undertaken. Two scoring rounds were undertaken for each observation method (totaling four scoring rounds) and an intra‐observer error test was performed. The averaged results of the two observation methods were compared via boxplots with paired cases. Results Intra‐observer error was negligible and non‐significant. Scoring results are comparable between the two observation methods. Notwithstanding, some differences were found, in which CT scan assessment generally overestimates dental wear when compared to direct observation. Discussion Our results generally validate the use of CT scans in studies of dental wear magnitude. Notwithstanding several caveats relating to CT scanning and visualization limitations should be considered to avoid over or under‐estimation of dental wear.

Mandibular morphology and the Mesolithic–Neolithic transition in Westernmost Iberia

“…Dental wear was scored by the same observer (RMG), preventing inter-observer error. Although not all teeth were observed multiple times, a previous study with a sub-sample (n = 412) of the one used in this study showed no scoring differences between repeated observations by the same observer 126 . Dental wear scores of paired first and second molars were plotted using the ggplot2 package of R 92 .…”