Mallar Kavya B, Girish H C, Murgod Sanjay, Kumar Bn Yathindra
Department of Oral Pathology, Rajarajeswari Dental College and Hospital, Bengaluru, Karnataka, India.
J Oral Maxillofac Pathol. 2015 Sep-Dec;19(3):396-404. doi: 10.4103/0973-029X.174620.
Age estimation is an important factor in the identification of an individual in forensic science. Research indicates that cemental annulations may be used more reliably than other morphological or histological traits of human skeleton for age estimation.
Twenty-five teeth were sectioned longitudinally, and twenty-five teeth were cross-sectioned at the mid portion of the root. Sections were ground, mounted and viewed under a bright light microscope. The area selected for counting was photographed under ×10 objective, magnified 5 times; cemental lines were counted and added to the eruption age of that patient, to obtain the chronological age. The statistical software SAS 9.2, SPSS 15.0, Stata 10.1, MedCalc 9.0.1, Systat 12.0 and R environment ver.2.11.1 were used for the analysis of the data.
The P value comparing actual age and calculated age using longitudinal sections is moderately significant and the P value comparing actual age and calculated age in the age group of <30 years is significant.
The middle third of tooth root was most suitable to count annulations. The cross sections are easier to count but longitudinal sections give more appropriate results on age estimation. Though the procedure predicts under assessment of age in the younger age group and over assessment of age in the older age group, it provides a close estimate of the actual age of an individual. It can be correlated with other age estimation methods for better reliability.
年龄估计是法医学中个体识别的一个重要因素。研究表明，与人类骨骼的其他形态学或组织学特征相比，牙骨质年轮可能更可靠地用于年龄估计。
25颗牙齿纵向切片，25颗牙齿在牙根中部横向切片。切片进行研磨、固定，并在明视野显微镜下观察。选择用于计数的区域在×10物镜下拍照，放大5倍；计算牙骨质线的数量，并将其与该患者的萌出年龄相加，以获得实际年龄。使用统计软件SAS 9.2、SPSS 15.0、Stata 10.1、MedCalc 9.0.1、Systat 12.0和R环境ver.2.11.1对数据进行分析。
使用纵向切片比较实际年龄和计算年龄的P值具有中度显著性，在<30岁年龄组中比较实际年龄和计算年龄的P值具有显著性。
牙根中部最适合计数年轮。横断面更容易计数，但纵向切片在年龄估计方面给出的结果更合适。尽管该方法在较年轻年龄组中预测年龄偏低，在较年长年龄组中预测年龄偏高，但它能提供个体实际年龄的近似估计。它可以与其他年龄估计方法相关联以提高可靠性。
