Marchand Elodie, Bertrand Benoit, Hedouin Valéry, Demondion Xavier, Becart Anne
Unité de Taphonomie Médico-Légale et Anatomie, ULR 7367, Faculté de Médecine, Université de Lille, 59000 Lille, France.
CHRU Nancy, Service de Médecine Légale, 54000 Nancy, France.
Diagnostics (Basel). 2023 Aug 30;13(17):2808. doi: 10.3390/diagnostics13172808.
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.
在法医学领域，人类遗骸的鉴定是一个反复出现的问题。估计死亡年龄是众多需要评估的标准之一。在成人牙齿中，牙根牙本质透明度的高度用于估计年龄。然而，在考古材料中，这种现象似乎并不稳定。这项工作的目的是观察不同死后间隔时间牙齿中硬化牙本质的结构变化。该研究包括两个部分（回顾性和前瞻性研究），使用了21颗人类单根牙，这些牙齿来自捐赠给医学的尸体，死后间隔时间（PMI）分别为0、1、2和5年以及考古发掘所得。基于树脂包埋、切片和抛光后，使用扫描电子显微镜（SEM）JSM - 7800F对样本进行分析，并通过能量色散X射线微分析（EDX）对钙和磷进行半定量分析来完成整个过程。分析表明，在不同的PMI下，硬化牙本质存在管状和化学变化。我们的扫描电子显微镜研究使我们能够观察到与PMI增加相关的小管形态差异：管周环的丧失以及小管腔被高密度物质阻塞。微分析突出了不同组之间磷钙比的变化，尤其是在牙髓区域和犬齿中。我们解释这些差异的假设基于硬化牙本质矿相晶体在化学和/或细菌作用影响下的死后变化。
