On manual laterality (handedness) in humans and its forensic significance - a literature review.

Manual laterality (handedness) in humans has some significance for forensic practice where it is primarily employed in the form of handedness preference, based on a simplified three-stage classification (right-handed, left-handed and ambidextrous). In cases of homicide or suicide, the pattern of injuries, particularly cutting or stab injuries and gunshot wounds, may provide clues as to the perpetrator's handedness. In injuries inflicted by another person, the pattern of findings can in isolated cases allow to draw conclusions as to the handedness of the perpetrator. In self-inflicted injuries and suicide, the dominant hand is usually used either alone or as the lead hand. If it is found that fatal injuries were inflicted by the non-dominant hand, this gives rise to doubt that the manner of death is suicide. Evidence of handedness is of little value in distinguishing between suicide and homicide. Due to new developments in dentistry, imaging procedures and especially genetics, the utility of handedness in the identification of unknown persons or cadavers has significantly diminished. In living subjects, useful evidence of handedness can be obtained by observing the performance of specific gestures or activities. The subject should be asked to perform tasks involving one and two hands in a specific sequence. Standardised measurements of the morphology of the shoulders and upper extremities are able to make a statistical distinction between right and left. Since the accuracy of this process is, however, only,around 75 %, morphological determination of handedness should not be used in living subjects, but should be restricted to the identification of unknown cadavers or other post-mortem examinations.

[Forensic age estimation in juveniles and young adults: Reducing the range of scatter in age diagnosis by combining different methods]. / Forensische Altersschätzung bei Jugendlichen und jungen Erwachsenen: Streubreitenreduktion der Altersdiagnose durch Kombination der Methoden.

The dramatic rise in the number of refugees entering Germany means that age estimation for juveniles and young adults whose age is unclear but relevant to legal and official procedures has become more important than ever. Until now, whether and to what extent the combination of methods recommended by the Study Group on Forensic Age Diagnostics has resulted in a reduction of the range of scatter of the summarized age diagnosis has been unclear. Hand skeletal age, third molar mineralization stage and ossification stage of the medial clavicular epiphyses were determined for 307 individuals aged between 10 and 29 at time of death on whom autopsies were performed at the Institutes of Legal Medicine in Berlin, Frankfurt am Main and Hamburg between 2001 and 2011. To measure the range of scatter, linear regression analysis was used to calculate the standard error of estimate for each of the above methods individually and in combination. It was found that combining the above methods led to a reduction in the range of scatter. Due to various limitations of the study, the statistical parameters determined cannot, however, be used for age estimation practice.

[Medicolegal identification of victims in mass disasters using the example of aircraft accidents]. / Rechtsmedizinische Identifizierungsaufgaben bei Katastrophen am Beispiel von Flugunfällen.

In mass disasters, the main task of the medicolegal expert is to support the victims' identification. As such events are rare, the knowledge obtained during previous operations should be evaluated and published to improve the quality and effectiveness of the identification work in future disasters. This report describes the experience gained at the Institute of Forensic Medicine of the Humboldt University in Berlin during the identification of the victims of three aircraft accidents (1972, 1986, 1989). The advantages and disadvantages of the identification methods used are discussed. Medicolegal experts should make themselves familiar with available experiences to be adequately prepared for the responsible task of identifying the victims in an emergency.

Forensic Age Estimation.

BACKGROUND: Forensic age estimation is requested by courts and other government authorities so that immigrants whose real age is unknown should not suffer unfair disadvantages because of their supposed age, and so that all legal procedures to which an individual's age is relevant can be properly followed. 157 age estimations were requested in Berlin in 2014, more than twice as many as in 2004. METHODS: This review is based on pertinent articles retrieved by a selective search in the PubMed and MEDPILOT databases, supplemented by relevant recommendations and by the findings of the authors' own research. RESULTS: The essential components of age estimation are the history, physical examination, X-rays of the hands, panorama films of the jaws, and, if indicated, a thin-slice CT of the medial clavicular epiphyses, provided that there is a legal basis for X-ray examinations without a medical indication. Multiple methods are always used in combination, for optimal accuracy. Depending on the legal issues at hand, the examiner may be asked to estimate the individual's minimum age and/or his or her most probable age. The minimum-age concept can be used in determinations whether an individual has reached the age of legal majority. It is designed to ensure that practically all persons classified as adults have, in fact, attained legal majority, even though some other persons will be incorrectly classified as minors. CONCLUSION: Forensic age estimation lets courts and other government authorities determine the official age of persons whose actual age is unknown-in most cases, unaccompanied refugees who may be minors. The goal is to carry out age-dependent legal procedures appropriately in accordance with the rule of law. The minimum-age concept is designed to prevent the erroneous classification of minors as legal adults.

Statistical analysis and verification of forensic age estimation of living persons in the Institute of Legal Medicine of the Berlin University Hospital Charité.

In recent years, the increase in international migration movements has led to a greater demand for forensic age estimation of foreigners without valid identification documents in numerous countries. The growing importance of forensic age determination is underlined by a rapid rise in the number of expert reports by the Institute of Legal Medicine of the Berlin University Hospital Charité. A total of 247 expert opinions on estimated age were given between 1992 and 31 December 2000. Subject to formal court ruling, age is estimated based on the physical inspection, in combination with an X-ray of the left hand and the clavicles as well as dental assessment. However, the statistical proof of the range of scatter for the summarized age diagnosis still remains to be clarified in the context of this assessment procedure. The age estimations made by the Institute of Legal Medicine of the Berlin University Hospital Charité were statistically analyzed with respect to the validity of the different methods. For verification of the age diagnoses, the age estimates were compared with the court records and the age determined in the course of legal proceedings. In 45 cases, the age diagnoses could be verified. In all cases where the age could be verified beyond doubt, deviations from the actual age did not exceed +/-12 months. From this, it can be concluded that the combined application of the above-mentioned methods allows forensic age estimations with a sufficiently high degree of reliability.

Studies on the chronology of third molar mineralization in a Japanese population.

In Germany, a sharp increase in forensic age estimations of living individuals has been observed in recent years. With regard to the relevant age group, radiologic assessment of the mineralization stage of the third molars is of particular importance. Still, the influence of ethnicity on the pace of mineralization has been insufficiently analyzed. A total of 1615 orthopantomograms of 929 female and 686 male Japanese subjects aged between 12 and 30 years was examined. The mineralization stages of third molars were evaluated on the basis of Demirjian's stages modified in accordance with Mincer's model. For the individual mineralization stages, the study presents the means and standard deviations for the genders separately. No statistically significant differences in the chronology of third molar mineralization between maxilla and mandible and between sides were observed. A comparison between genders largely did not render significant differences either. Apart from forensic age determination in living subjects, the presented reference data can also be used for age estimations of unidentified corpses and skeletons.

Comparative study on the chronology of third molar mineralization in a Japanese and a German population.

In Germany, a sharp increase in forensic age estimations of living persons has been observed in recent years. German law defines four legally relevant age limits: 14, 16, 18 and 21 years. In these age groups, radiographic assessment of the mineralization status of third molars is of particular importance. So far, the influence of ethnicity on the mineralization rate has been insufficiently analyzed. A total of 3031 orthopantomograms of 1597 Japanese and 1434 Germans aged between 12 and 26 years were examined. The mineralization status of third molars was evaluated on the basis of the classification proposed by Demirjian. For the individual mineralization stages, the study presents the mean values and standard deviations (SD) separately for both populations and sexes. The majority of probands from both the Japanese and the German population achieved the C stage and the late G and H stages of third molar development at similar ages. Significant differences between Japanese and Germans were observed, however, with regard to the D, E and F stages defined by Demirjian. Japanese men and women achieved the D, E and F stages approximately 2-3 years later than German men and women. In addition to forensic age determination in living persons, the presented reference data can also be used for age estimations of unidentified deceased persons and skeletons.

[Radiologically determined DMF index variations for forensic age estimation of young adults]. / Radiologisch bestimmte Varianten des DMF-Index zur forensischen Altersschätzung bei jungen Erwachsenen.

The eruption and mineralization of third molars are the main criteria for dental age estimation of living people involved in criminal proceedings. Since the development of third molars is usually completed by the age of 19 or 20 years, this feature cannot be used to ascertain whether a person has attained the forensically relevant age of 21 years. This study examined whether the DMFT index or the third molar DFT index could supply reliable information enabling conclusions to be drawn about whether a person has reached the age of 21. To this end, 650 conventional orthopantomograms of German subjects aged 18 to 30 years were evaluated. The DMF index variations considered were found to be unsuitable for determining whether a person is over 21 because they displayed a weak correlation with age and considerable individual scatter. A high indicative value can only be attributed to a third molar DFT index of 4, although this is rarely observed in the relevant age group. An X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person has attained 21 years of age.

The current state of forensic age estimation of live subjects for the purpose of criminal prosecution.

In recent years, many countries have experienced a sharp increase in the demand for forensic age estimates of live persons. From a legal perspective, such age estimates are carried out to determine whether a suspect without valid identity documents has reached the age of criminal responsibility and whether general criminal law in force for adults applies. In many countries, the age thresholds of relevance to criminal prosecution lie between 14 and 21 years.In line with recommendations issued by the Study Group on Forensic Age Diagnostics for determining the age of live subjects in criminal proceedings, a forensic age estimate should combine the results of a physical examination, an x-ray of the hand, and a dental examination that records dentition status and evaluates an orthopantomogram. In addition, a radiological or computed tomographic examination of the clavicles is recommended to establish whether a person has attained 21 years of age.This article addresses the influence of ethnicity on the examined developmental systems. In so doing, the authors conclude that forensic age estimates should pay due heed to the proband's socioeconomic status and ethnic origin.

Validation of common classification systems for assessing the mineralization of third molars.

One major criterion for dental age estimation is the evaluation of third molar mineralization. There are various methods for evaluating tooth mineralization based on classification by stages. The aim of the present work is to assess the validity of the common classification systems. To this end, we analyzed 420 conventional orthopantomograms of German females aged 12-25 years old. The mineralization status of tooth 38 was determined using the stages defined by Gleiser and Hunt, Demirjian et al., Gustafson and Koch, Harris and Nortje and Kullman et al., respectively. Of the methods tested, the most accurate results were obtained with Demirjian et al.'s classification system, which performed best not only for observer agreement but also for the correlation between estimated and true age. It is argued that this is due to the fact that Demirjian et al.'s classification is based on a sufficient number of stages which are defined independently of speculative estimations of length. This leads to the conclusion that the method devised by Demirjian et al. should be used for evaluating the mineralization of third molars for purposes of forensic age determination.

Forensic age estimation in living subjects: the ethnic factor in wisdom tooth mineralization.

Radiological assessment of the mineralization stage of third molars is a major criterion for age estimation of living people involved in criminal proceedings. To date insufficient knowledge has been obtained about how the ethnic origin can influence tooth mineralization. A comparative study of wisdom tooth mineralization was carried out on three population samples: one German, one Japanese and one South African. To this end, 3,652 conventional orthopantomograms were evaluated on the basis of Demirjian's stages. The Japanese subjects were on average 1-2 years older than their German counterparts upon reaching stages D-F, whereas the South African subjects were on average 1-2 years younger than the Germans when displaying stages D-G. To enhance the accuracy of forensic age estimates based on wisdom tooth mineralization we recommend the use of population-specific standards.