Department of Histology and Developmental Biology, Tokyo Dental College, 2-9-18 Kanda-Misakicho, Chiyoda, Tokyo, 101-0061, Japan.
Department of Forensic Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.
Int J Legal Med. 2019 Sep;133(5):1421-1427. doi: 10.1007/s00414-019-02020-5. Epub 2019 Feb 15.
The present investigation was performed with the objective of developing a method to estimate how long a corpse had been immersed in water after death (the time since death). Accurate determination of the time elapsed since death may lead to identification of the place of drowning, and therefore, serves not only as a piece of information useful for determination of the cause of death but also leads to prompt identification of the body. The results showed that diatoms attached to the surface of dental enamel increased with prolongation of immersion time in water. Further, as the immersion time increased, the quantity of O, Si, Mg, K, Al, and S detected on the surface of dental enamel increased, while the quantity of the main dental components (Ca and P) that were detected gradually decreased. Based on these results, we calculated a regression formula to estimate the immersion time. Our method is considered to be a breakthrough technique for evaluating the time since death more objectively, compared to the conventional method of determination based on the degree of decomposition of the corpse.
本研究旨在开发一种估计死亡后尸体在水中浸泡时间（死后时间）的方法。准确确定死亡时间可以确定溺水地点，因此不仅可以作为确定死因的有用信息，而且可以迅速识别尸体。结果表明，附着在牙釉质表面的硅藻随着在水中浸泡时间的延长而增加。此外，随着浸泡时间的增加，在牙釉质表面检测到的 O、Si、Mg、K、Al 和 S 的数量增加，而被检测到的主要牙齿成分（Ca 和 P）的数量逐渐减少。基于这些结果，我们计算了一个回归公式来估计浸泡时间。与基于尸体分解程度的传统确定方法相比，我们的方法被认为是一种更客观地评估死亡时间的突破性技术。
