用扫描电子显微镜研究不同死后间隔的根透明度
Elodie Marchand1,2, Benoit Bertrand1,3, Valéry Hedouin1
1Unité de Taphonomie Médico-Légale et Anatomie, ULR 7367, Faculté de Médecine, Université de Lille, 59000 Lille, France.
Diagnostics (Basel, Switzerland)
|September 9, 2023
概括
硬化牙的结构变化揭示了死后间隔 (PMI) 的变化. 这些通过扫描电子显微镜观察到的牙修饰,有助于估计法医和考古学案例死后的时间.
科学领域:
- 法医人类学 法医人类学
- 牙科法医医学 牙科法医医学
- 古病理学 古病理学
背景情况:
- 准确的年龄估计对于在法医中识别人类遗骸至关重要.
- 根牙透明度是成年牙年龄估计的常用方法.
- 丹丁透明的可靠性在考古学背景下受到质疑,因为它不一致.
研究的目的:
- 通过各种死后间隔 (PMI) 调查硬化牙的结构变化.
- 评估硬化牙分析在法医和考古样本中估计死亡时间的实用性.
主要方法:
- 分析了21个人类单根牙,其PMI为0,1,2和5年,再加上考古样本.
- 样品的准备包括树脂的加入,切割和抛光.
- 扫描电子显微镜 (SEM) 和能量分散式X射线 (EDX) 微分析用于结构和化学评估.
主要成果:
- 随着PMI的增加,SEM揭示了明显的管状修饰,包括周管状项圈的损失和超密度物质阻塞的光线.
- EDX微分析显示了不同PMI的酸比率的变化,特别是在肉和犬类区域.
- 观察到的变化表明,死后对硬化牙的矿物阶段发生了改变.
结论:
- 硬化牙表现出与死后间隔相关的结构和化学变化.
- 这些修改有可能改善法医和考古人类遗骸的年龄估计.
- 假设化学和/或细菌作用驱动了硬化牙的死后变化.
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