The Off-season of Dental Cementum Investigations. A Critical Appraisal of Season-of-death Prediction in Medico-legal Investigations

• NCJ Number: 309645
• Author(s): Benoit Bertrand; Ahmad Kaddoura; Eugenia Cunha; Anne Bécart; Didier Gosse; Valery Hédouin; Carina Marques
• Date Published: August 2024
• Length: 9 pages
• Grant Number(s): 15PNIJ-23-GG-04229-SLFO
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)
• Award: Developing and Validating Standards for Dental Cementum Age-at-Death and Season-of-Death Estimation

Annotation

This article discusses the prospects and limitations of dental cementum as a method for estimating seasonality of death, by evaluating its accuracy in a documented sample with a standardized protocol; it also examines the differences between manual and software-assisted procedures on the accuracy of the season-of-death prediction.

Abstract

It has been suggested that death seasonality could be estimated based on the dark/bright appearance of the outermost dental cementum deposit. The few existing studies show variable accuracy rates. The question whether estimating season-of-death based on dental cementum represents a realistic and achievable goal can arise. This work, based on a software-assisted procedure and direct human observation, aims to critically evaluate the applicability of dental cementum to estimate the season-of-death in forensic anthropology. The sample consists of 20 canines from individuals belonging to the 21st century Identified Skeletal Collection, University of Coimbra, Portugal, and with documented biodemographic data. Fifty percent of the individuals died during the summer and 50 percent during the winter. Five non-decalcified 100 μm cross-sections per tooth were prepared, using a standardized protocol. Images of the region of interest, with the acellular cementum, were captured, and imported into FIJI/ImageJ software. Performance of the season-of-death predictions was very low, with 50 percent accuracy, score of 0.0000 for Matthews Correlation Coefficient, and F1-score of 61.5 percent for Summer and 28.6% for Winter, were obtained for the observer assessment. For the software model, performance was equally poor, with 52.6 percent accuracy, score of 0.0272 for Matthews Correlation Coefficient, and F1-score of 30.8 percent for Summer and 64.0 percent for Winter. This work is of relevance to the forensic science community by demonstrating the prospects and limitations of dental cementum as a method for estimating seasonality of death. (Published Abstract Provided)