Criteria of personal identification by the hyoid bone

We studied 16 sizes of the hyoid bone (HB) from 158 corpses of known gender, Russians, who had died at the age over 15 years by the K. Miller et al program (1998) and 205 back projection electroroentgenograms of the neck of patients of the traumatological hospital in the town of Kirov. HB skeletization was made by the enzymatic drug enzyme. SPSS package and multidimentional statistics (regression and discriminant analyses) were used for data processing. It was established that HB is an informative object of forensic medical personal identification allowing determination of the body length and gender as well as anatomical, x-ray and osteometric individual features. Precision of human body length diagnosis by HB is 6.71-7.26 cm. Therefore, this method should be used in combination with the diagnosis by long tubular bones. Diagnosis of human gender by osteometric signs of HB based on one-dimentional discriminant analysis is feasible in 80-85%, based on canonical discriminant analysis--in 91.1% cases. The method of anatomic, osteometric and roentgenological assessment of HB individuality can be used in personal identification by intravital x-ray of cervical organs and in traumatic defects of HB. The methods may be applied in forensic medical practice in expert examination of body fragments or isolated bone fragments.     

唾液酯酶多态性在个体识别中的应用研究

目的 探讨唾液酯酶（ Set）多态性在法医学亲权鉴定和个体识别方面的应用价值。方法 应用聚丙烯酰胺凝胶盘状电泳及固蓝 RR染色方法,调查了 114名中国人 Set的表型分布及基因频率,用χ 2检验进行统计学分析。结果 中国人酯酶表型频率 Set F 22.81％, Set FS 50.88％, Set S 26.31％ ;基因频率为 SetF 0.482 5, SetS 0.517 5;非父排除机率为 0.187 5,个体识别率为 0.619 9。结论 Set有较高的父权排除率和个体识别率,可作为法医学亲权鉴定和个体识别的重要标记系统之一。     

Analysis of enamel rod end patterns on tooth surface for personal identification--ameloglyphics

Ameloglyphics is the study of enamel rod end patterns on a tooth surface. Our aim was to study the in vivo analysis of enamel rod end patterns on tooth surfaces for personal identification. In this study, the maxillary left canine and 1st premolar of 30 men and 30 women were included. The cellulose acetate peel technique was used to record enamel rod endings on tooth surfaces. Photomicrographs of the acetate peel imprint were subjected to VeriFinger Standard SDK v5.0 software for obtaining enamel rod end patterns. All 120 enamel rod end patterns were subjected to visual analysis and biometric analysis. Biometric analysis revealed that the enamel rod end pattern is unique for each tooth in an individual. It shows both intra- and interindividual variation. Enamel rod end patterns were unique between the male and female subjects. Visual analysis showed that wavy branched subpattern was the predominant subpattern observed among examined teeth. Hence, ameloglyphics is a reliable technique for personal identification.     

The use of odontograms and panoramic roentgenography in personal identification]

Study of dental root surfaces prompted the authors to add to the routine odontogram 28 more maxillary surfaces and 22 mandibular surfaces, this making a total of 210 diagnostic signs. Employment of amplified panoramic roentgenography permitted the authors to detect specific features of the dental cavity, root canals, periodontal fissure structure, the presence of caries and its complications, inflammatory and systemic involvement, injury to the jaws and teeth. Visual examination of dental status and application of panoramic roentgenography will help improve forensic medical personal identification.     

Radiographic personal identification with characteristic features in the hip joint.

This case demonstrates a radiographic personal identification. A body was found but no positive results were obtained from the remains regarding the cause of death, the manner of death, or precise identification. At the autopsy, a characteristic radiographic deformity was found in the hip joints. After searching the registry of persons with congenital acetabular dysplasia and super-imposing the postmortem radiograph on the films of the registry, the identification was successful.     

Application of superimposition-based personal identification using skull computed tomography images

Superimposition has been applied to skulls of unidentified skeletonized corpses as a personal identification method. The current method involves layering of a skull and a facial image of a suspected person and thus requires a real skeletonized skull. In this study, we scanned skulls of skeletonized corpses by computed tomography (CT), reconstructed three-dimensional (3D) images of skulls from the CT images, and superimposed the 3D images with facial images of the corresponding persons taken in their lives. Superimposition using 3D-reconstructed skull images demonstrated, as did superimposition using real skulls, an adequate degree of morphological consistency between the 3D-reconstructed skulls and persons in the facial images. Three-dimensional skull images reconstructed from CT images can be saved as data files and the use of these images in superimposition is effective for personal identification of unidentified bodies.     

咬痕个体识别的比对方法

目的 建立一个牙模数据库,为通过牙齿、咬痕进行个人识别的研究及其在法医实践中的应用提供一种新方法。方法 经过对400例牙模进行分析、计算,将牙齿的形状、排列转换成数字型(X,Y)坐标,通过计算出每颗牙关键点与坐标原点的相对位置,在DOS系统下运用Borland C++5.0语言编写程序,快速地计算出牙齿和牙弓的特征。结果 能对牙模进行自动识别,达到排除与认定。其比对精度长度为1.3mm,角度3°;可取的最少牙点位数目为12～14较为合理,大致需要5～7个完整的牙痕。结论 该方法是研究咬痕与牙模比对的基础。     

Proposal for internet-based Digital Dental Chart for personal dental identification in forensics

A dental chart is very useful as a standard source of evidence in the personal identification of bodies. However, the kind of dental chart available will often vary as a number of types of odontogram have been developed where the visual representation of dental conditions has relied on hand-drawn representation. We propose the Digital Dental Chart (DDC) as a new style of dental chart, especially for open investigations aimed at establishing the identity of unknown bodies. Each DDC is constructed using actual oral digital images and dental data, and is easy to upload onto an Internet website. The DDC is a more useful forensic resource than the standard types of dental chart in current use as it has several advantages, among which are its ability to carry a large volume of information and reproduce dental conditions clearly and in detail on a cost-effective basis.     

The personal identification of many samples recovered from under the sea

An automatic and rapid DNA typing system was employed for personal identification, using fragmentary tissue samples from victims in an airplane accident. Two victims were crushed into small pieces, and 33 samples suspected to belong to them were recovered from under the sea. From each sample, 10 mg was used for testing. The parents' bloods of two presumptive victims were also examined. DNA extraction from samples was performed by the NaI method, and the obtained DNA samples were analyzed with the ABI PRISM system. Among 33 samples, 31 samples were identified to be human tissues, possibly from two victims. The other two samples seemed to be parts of marine animals. ABO blood group, STR polymorphism, and mitochondrial DNA polymorphism typing were possible in every examined human sample. Two victims' fragmentary tissues were identified by determining ABO genotype, STR type and mitochondrial DNA type. The system we employed enabled an accurate typing of many fragmentary samples in a short time, thus contributing to the fast and secure identification of many victims in such cases as big air accidents.     

Indication and limitations of using palatal rugae for personal identification in edentulous cases

To explore the availability and the limitations of using the palatal rugae pattern in forensic practice for personal identification in edentulous cases, we set up an experiment, which involved 48 patients who had both old and new complete dentures and we observed their rugae. First, we made 48 pairs of maxillary casts from their old and new dentures and a further 50 maxillary casts from complete dentures at random, to use as variables. All the initial impressions taken from the mucosal surfaces of complete dentures were made from alginate impression materials, and the maxillary casts were made from hard dental plaster. Secondly, all 146 casts were trimmed so that all the areas except for the rugae area were removed. Subsequently, 50 examiners were given the 48 casts from the old dentures and were then asked to compare them with the other 98 casts for possible matches. The case numbers, which matched correctly, were recorded. The median percentage of correct matches among the 50 examiners was 94%, despite variations in their experience with forensic identification, and this accuracy does not differ significantly from that in dentate cases, as described in previous publications. The median percentage of correct matches among the 48 cases was 90%. Analyzing the incidence of obtaining a correct match in each case revealed that there were three major misleading shapes that could give rise to a low rate of correct matches; (1) severely low and poorly demarcated eminences of rugae, (2) change of palatal height, and (3) non-complex rugae pattern. These features are mainly due to the shape of the edentulous palate itself and rarely due to the dentures, and could lead to difficulties in finding unique points for use in matching rugae patterns. The results suggest that an appropriate selection of cases, taking into consideration the above misleading shapes, may establish an increased rate of accuracy for identification with this method, thereby bringing the percentage of correct matches closer to 100% in edentulous cases, which is also the percentage of correct matches previously reported in dentate cases.     

Comparative characteristics of angulometric parameters of teeth and dentitions in terms of personal identification

Angulometric teleroentgenographic characteristics of teeth were compared for 158 subjects. A computer technology of calculation and assessment of 47 angular (quantitative) parameters characterizing spatial position of the teeth and jaws is proposed. This complex of parameters can be used as an additional test in personal identification.     

The possibility of using malposition of tooth rows for the subject identification

Described in the paper is the possibility of using the specific anomalies of tooth rows in personality identification. The existing classifications of tooth-row anomalies are elucidated; published data on epidemiology of dentomaxillary anomalies in the Russian Federation and on jaw models are analyzed. Digital photos of tooth rows were used. The possible use of orthodontic methods as applicable to investigating the tooth-row anomalies is contemplated for personality identification.     

Associated postmortem dental findings as an aid to personal identification.

The use of the unique features of the human dentition to aid in personal identification is well accepted within the forensic field. Indeed, despite advances in DNA and other identification methodologies, comparative dental identifications still play a major role in identifying the victims of violence, disaster or other misfortune. The classic comparative dental identification employs the use of postmortem and antemortem dental records (principally written notes and radiographs) to determine similarities and exclude discrepancies. In many cases the tentative identification of the individual is unknown and therefore antemortem records cannot be located. In such a situation a dental profile of the individual is developed to aid the search for the individual's identity. With such a profile a forensic odontologist can identify and report indicators for age at time of death, race (within the four major ethnic groups) and sex. In addition to these parameters the forensic dentist may be able to give more insight into the individual. This paper outlines, for the non-expert, some of the additional personal information that can be derived from the teeth of the deceased, and which may assist in their ultimate identification.     

Polymorphism of structural genes of human mitochondrial DNA for forensic medical personal identification

An experimental study is described, which deals with polymorphism of nucleotide sequences of three structural genes of mitochondrial genome, i.e. of the 3d, small 4th, and 6th subunits of the NADN dehydrogenase complex (ND3, ND4L and ND6) sampled from Russian population. The genetic primary structure was analyzed in 63 unrelated individuals. The investigated locuses were shown to possess a pronounced polymorphism. A total of 19 polymorphic positions were detected in the ND3, ND4L and ND6 gene region within the studied sampling. Besides, a possibility is demonstrated in the paper that the mtDNA structural genes can be used as additional identification markers in the forensic experimental typing of the mtDNA control region.     

The diversity of adult dental patterns in the United States and the implications for personal identification

Few would argue about the individuality of dental radiographs for forensic identification, but when an antemortem/postmortem comparison is based strictly on dental treatment notes and/or charts it becomes less certain. In the past, attempts to validate the high diversity of dental patterns created by combinations of missing, filled, and unrestored teeth have been based on unfounded statistical assumptions. The goal of this research is to present a statistically valid method of assessing dental pattern diversity for the identification of missing individuals. Empirical observation of large reference datasets was found to be the best technique for assessing dental diversity. This technique is nearly identical to the procedure used for mitochondrial DNA casework. For the research presented in this paper, two large datasets were used, one composed of U.S. military personnel and one composed of U.S. civilians. Dental patterns were found to be very diverse on a scale that is comparable to mtDNA. In addition, it was found that the diversity values remain very consistent regardless of the level of detail present in the treatment records. Overall, combinations of missing, filled, and unrestored teeth were found to be very individualistic and an excellent source for forensic identification.     

The intergroup variability and sex dimorphism in the size of the human dental arches in personal identification]

The morphology of dental arch has been studied in representatives of 11 contrast (by anthropological characteristics) ethnic groups from regions of their compact residence. The sampling from each ethnic group consisted of 200 subjects (100 male and 100 female) aged 13-20 years. A total of 4,500 plaster models of dental arches were examined. The results were statistically processed using factor, canonical, discriminant analyses, and multidimensional scanning. The data on the variability and sex dimorphism in the size and shape of dental arches in subjects belonging to different ethnic groups may be practically significant in forensic medical personality identification.