Carrasco Patricio A, Brizuela Claudia I, Rodriguez Ismael A, Muñoz Samuel, Godoy Marianela E, Inostroza Carolina
Universidad de los Andes, Dental School Santiago, Mons. Álvaro del Portillo 12.455, Las Condes, Santiago PO7620001, Chile.
Universidad de los Andes, Dental School Santiago, Mons. Álvaro del Portillo 12.455, Las Condes, Santiago PO7620001, Chile.
Forensic Sci Int. 2017 Oct;279:251-257. doi: 10.1016/j.forsciint.2017.09.001. Epub 2017 Sep 11.
The correct estimation of the post mortem interval (PMI) can be crucial on the success of a forensic investigation. Diverse methods have been used to estimate PMI, considering physical changes that occur after death, such as mortis algor, livor mortis, among others. Degradation after death of dental pulp is a complex process that has not yet been studied thoroughly. It has been described that pulp RNA degradation could be an indicator of PMI, however this study is limited to 6 days. The tooth is the hardest organ of the human body, and within is confined dental pulp. The pulp morphology is defined as a lax conjunctive tissue with great sensory innervation, abundant microcirculation and great presence of groups of cell types.
The aim of this study is to describe the potential use of pulp post mortem alterations to estimate PMI, using a new methodology that will allow obtainment of pulp tissue to be used for histomorphological analysis. The current study will identify potential histological indicators in dental pulp tissue to estimate PMI in time intervals of 24h, 1 month, 3 months and 6 months.
This study used 26 teeth from individuals with known PMI of 24h, 1 month, 3 months or 6 months. All samples were manipulated with the new methodology (Carrasco, P. and Inostroza C. inventors; Universidad de los Andes, assignee. Forensic identification, post mortem interval estimation and cause of death determination by recovery of dental tissue. United State patent US 61/826,558 23.05.2013) to extract pulp tissue without the destruction of the tooth. The dental pulp tissues obtained were fixed in formalin for the subsequent generation of histological sections, stained with Hematoxylin Eosin and Masson's Trichrome. All sections were observed under an optical microscope using magnifications of 10× and 40×.
The microscopic analysis of the samples showed a progressive transformation of the cellular components and fibers of dental pulp along PMI. These results allowed creating a chart of qualitative and quantitative parameters to be used on the estimation on PMI based on microscopic degradation of dental pulp.
The histological transformations of dental pulp as a function of time can be used as PMI indicators.
准确估计死后间隔时间（PMI）对于法医调查的成功至关重要。考虑到死后发生的身体变化，如尸冷、尸斑等，人们使用了多种方法来估计PMI。牙髓死后降解是一个尚未得到充分研究的复杂过程。据描述，牙髓RNA降解可能是PMI的一个指标，然而该研究仅限于6天。牙齿是人体最坚硬的器官，牙髓位于其中。牙髓形态被定义为一种疏松的结缔组织，具有丰富的感觉神经支配、大量的微循环以及大量的细胞类型群。
本研究的目的是描述牙髓死后改变在估计PMI方面的潜在用途，采用一种新方法，该方法将允许获取用于组织形态学分析的牙髓组织。当前研究将识别牙髓组织中的潜在组织学指标，以估计24小时、1个月、3个月和6个月时间间隔内的PMI。
本研究使用了来自已知PMI为24小时、1个月、3个月或6个月个体的26颗牙齿。所有样本均采用新方法（卡拉斯科，P.和伊诺斯特罗萨C.发明人；安第斯大学，受让人。通过回收牙齿组织进行法医鉴定、死后间隔时间估计和死因判定。美国专利US 61/826,558 2013年5月23日）进行处理，以提取牙髓组织而不破坏牙齿。所获得的牙髓组织用福尔马林固定，随后制作组织切片，用苏木精-伊红和马松三色染色。所有切片在光学显微镜下以10倍和40倍放大倍数进行观察。
对样本的显微镜分析显示，随着PMI的延长，牙髓的细胞成分和纤维发生了渐进性变化。这些结果使得能够创建一个基于牙髓微观降解来估计PMI的定性和定量参数图表。
牙髓的组织学变化作为时间的函数可被用作PMI指标。
