ABSTRACT
In the fields of forensics, the identification of human remains is a recurrent problem. The estimated age at death is one of the copious criteria to be evaluated. In adult teeth, the height of the root dentin transparency is used to estimate age. However, in archaeological material, this phenomenon appears inconstant. The aim of this work was to observe the structural modifications of the sclerotic dentin in the teeth for different postmortem intervals. The study included two parts (retrospective and prospective study) with 21 human monoradicular teeth, from bodies donated to medical science with postmortem intervals (PMIs) of 0, 1, 2 and 5 years and archeological excavation. After inclusion based on resin, section and polishing, the samples were analyzed with a scanning electron microscope (SEM) JSM-7800F®, and the procedure was completed via a semiquantitative analysis of calcium and phosphorus using EDX microanalysis. The analysis showed the existence of tubular and chemical modifications of sclerotic dentin at different PMIs. Our SEM study allowed us to observe a difference in tubule aspects linked to an increased PMI: the loss of peritubular collar and the lumen obstruction of tubules with a hyperdense material. Microanalysis highlighted variations in phosphocalcic ratios among the different groups, especially in the pulp area and the canine. Our hypotheses that explain these differences are based on the postmortem modifications of the crystals of the mineral phase of sclerotic dentin under the influence of chemical and/or bacterial action.
ABSTRACT
Suchey-Brooks method has been studied many times with varying reports of accuracy and reliability. A systematic review and meta-analyses were utilized to quantitatively determine the accuracy and reliability of the Suchey-Brooks (S-B) method. A systematic search of PubMed and EBSCO health and medical databases was performed. Meta-analyses were performed to quantify the relationship between actual known age at death and the S-B method using Spearman's Rho and Pearson's r for (1) combined males and females estimates, (2) male-only estimates, and (3) female-only estimates. Overall correlation coefficient using Cohen's kappa, Spearman's Rho, and Pearson's r was also calculated to determine the interrater and intrarater reliability using the S-B method. Eighteen studies classified as moderate-to-high methodological quality met the inclusion criteria. The sample sizes were different for the combined male and female (n = 2620), male-only (n = 2602), and female-only (n = 1431) meta-analyses. The effect size of the age at death meta-analyses was large and significant for combined males and females (Spearman's Rho = 0.62; Pearson's r = 0.65), male-only (Spearman's Rho = 0.77; Pearson's r = 0.75), and female-only (Spearman's Rho = 0.71; Pearson's r = 0.71). The overall correlation coefficients of the interrater (Kappa = 0.76; Spearman's Rho = 0.73; Pearson's r = 0.80) and intrarater (Kappa = 0.81; Spearman's Rho = 0.91; Pearson's r = 0.83) reliability meta-analyses were large and significant. A significant degree of heterogeneity was present in all meta-analyses, with minimal evidence of publication bias. The meta-analyses results suggest the S-B method is highly reliable with a moderate-to-high degree of accuracy. Our results also identified sample size and accuracy differences between male and female individuals.