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A Schmeling

Publications and source records attributed to A Schmeling.

At least 19 recordsLinked to original sources
PubMed2006

Age estimation.

While age estimation of unidentified corpses and skeletons for identification purposes has a long tradition in forensic sciences, age estimation of living persons has formed a relatively recent area of forensic research which is becoming increasingly important. The international interdisciplinary Study Group on Forensic Age Diagnostics (AGFAD) issued recommendations for age estimation of living persons for the purpose of criminal, civil, asylum and old-age pension procedures as well as for determining the sex and age of skeletons. In the present work, the authors set out state-of-the art age estimation methods for specific case groups, define minimum requirements for reference studies and specify the need for further research. In addition, ethical and medico-legal aspects as well as issues relating to quality assurance are discussed.

Age Determination by Skeleton↗
PubMed2006

Studies on the progress of third-molar mineralisation in a Black African population.

The forensic determination of the age of living people has become increasingly important in recent years. With regard to the relevant age group, the radiographic assessment of third-molar mineralisation is of particular importance. So far, the influence of geographic origin on the mineralisation rate has been insufficiently analysed. The paper is based on a total of 595 conventional orthopantomograms of 474 male and 121 female Black Africans aged between 10 and 26 years for whom dates of birth were known. The mineralisation status of third molars was evaluated based on Demirjian's classification of stages [Demirjian et al., 1973. A new system of dental age assessment. Hum. Biol. 45, 221-227]. This study presents the means and standard deviations, median values and the lower and upper quartiles separately for both sexes for the mineralisation stages D-H. Statistically significant differences between the upper and lower jaws were observed in males examined with regard to their attaining the stage F. Mandibular teeth developed 0.8 years earlier than maxillary teeth. Significant sex-specific differences were found with regard to the age at which tooth 38 reached the stage G. In females, tooth 38 reached stage G 1.5 years earlier than in males. In comparison to White probands, the Black African sample showed a tendency to achieve the mineralisation stages earlier. We would recommend using population-specific standards for age determination purposes.

Adolescent↗
PubMed2006

Age estimation of unaccompanied minors. Part I. General considerations.

In recent years many countries have experienced a sharp increase in the demand for forensic age estimates of unaccompanied minors. In many countries the age thresholds of relevance to criminal prosecution lie between 16 and 22 years. In line with recommendations issued by the Study Group on Forensic Age Diagnostics, for determining the age of live subjects a forensic age estimate should combine the results of a physical examination, an X-ray of the hand and a dental examination which records dentition status and evaluates an orthopantomogram. To assess the age of persons who are assumed to be at least 18 years old, an additional radiographic or CT examination of the collar bones is recommended. Forensic age estimates should take account of the ethnic origin and socio-economic status of the person under examination.

Adolescent↗
PubMed2006

Age estimation of unaccompanied minors. Part II. Dental aspects.

Recent years have brought a worldwide increase in cross-border migration due to a globalized economy and ongoing belligerent conflicts. As a result, the percentage of foreigners among the general population has steadily increased not only in Germany, but also in other countries. This trend has triggered a growing demand for forensic medicine to assess the age of adolescents and young adults. The individuals examined here are unaccompanied minors without valid identification documents who do not know their age or else are suspected of not giving their correct age. The mineralization of third molars is the main criterion for dental age estimation of living subjects in the relevant age group. To date insufficient knowledge has been obtained about how ethnic origin can influence tooth mineralization. This, however, constitutes a restraint on the reliability of age estimates and hence on the forensic value of information essential to legal security. A comparative study was conducted to present comparative data on third molar mineralization in a Caucasoid, Mongoloid and African sample. In conclusion, forensic age estimates of living subjects would be more powerful tools if population-specific standards were applied to evaluations of wisdom tooth mineralization. Since the mineralization 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. The question was whether determination based on an orthopantomogram of a combination of features relevant to dental age estimation of adults supplies forensically useful information for ascertaining whether a person has attained 21 years of age. The features considered include the DMFT index of all permanent teeth, the DMFT index of all permanent teeth excluding third molars and the DFT index of third molars projecting beyond the occlusal plane. It can be concluded that an evaluation of the variations of the DMFT index does not by itself yield sufficient data to determine with the accuracy required in criminal proceedings whether a person has attained 21 years of age. An additional X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person is over 21.

Adolescent↗
PubMed2005

Combined determination of selected radiological and morphological variables relevant for dental age estimation of young adults.

The mineralisation of third molars is one of the main criteria for dental age estimation of living subjects in criminal proceedings. Since the mineralisation 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 determination based on an orthopantomogram of a combination of features relevant to dental age estimation of adults, supplies forensically useful information for ascertaining whether a person has attained 21 years of age. The features considered include the DMFT index of all permanent teeth, the DMFT index of all permanent teeth excluding third molars, the DFT index of third molars projecting beyond the occlusal plane, the eruption of third molars and the periodontal recession of second molars. A total of 650 conventional orthopantomograms of German subjects aged 18-30 years were evaluated. The statistical evaluation of our results was based on a discriminant analysis. It was carried out with two classes defined by two age groups: < or = 21 years and > 21 years. The probability of correct classification was 69.7% for males and 71.4% for females. It can be concluded that an evaluation of the variables reviewed in this paper does not by itself yield sufficient data to determine with the accuracy required in criminal proceedings whether a person has attained 21 years of age. The additional radiographic examination of the medial clavicular epiphyseal cartilage is recommended.

Adolescent↗
PubMed2004

Forensic age diagnostics of living people undergoing criminal proceedings.

In the German-speaking area, recent years have seen a rapid growth of the need for forensic age estimations. Such need arises, for example, if no verified information on the age of a person suspected of a criminal offence is available; the issue at question in terms of criminal law is whether the person concerned has reached the age of criminal responsibility and whether general criminal law in force for adults is to be applied. The relevant age tresholds in criminal proceedings are 14, 18 and 21 years of age. According to recommendations of the Study Group on Forensic Age Diagnostics, a forensic age estimate should consist of a physical examination, an X-ray of the hand, and a dental examination which records dentition status and evaluates an orthopantomogram. In addition, a radiological or CT examination of the clavicles is recommended to establish whether a person has attained 21 years of age. The present article addresses the influence of ethnic origin on the examined developmental systems.

Age Determination by Skeleton↗
PubMed2004

Locked internal fixator: sensitivity of screw/plate stability to the correct insertion angle of the screw.

OBJECTIVE: Internal fixators with angular stability have been developed to provide high stability without compression of the plate on to the bone. Angular and axial stability of a plate-screw construct can be achieved using a conically threaded screw head undersurface and a corresponding conically threaded plate hole. Furthermore, the insertion angle of the screw must correspond precisely to the axis of the screw hole. This is not always achieved in clinical practice and may result in screw loosening. The objective of this study was to examine the relationship between the stability of the locked screw-plate on the insertion angle of the screw. METHODS: Locking screws were inserted in an isolated (Point Contact Fixator, PC-Fix) or combined (Locking Compression Plate, LCP 4.5) locking hole with the use of an aiming device. The optimal insertion angle for these plates is perpendicular to the plate surface. The screws were inserted with an axis deviation of 0 degrees (optimal condition), 5 degrees , and 10 degrees respective to the optimal angle (variance +/- 1 degrees ). The samples were tested under shear or axial (push out) loading conditions until failure occurred. An Instron materials testing machine was used. RESULTS: Locking screws inserted in the isolated locking hole (PC-Fix) showed a significant decrease of failure load if inserted at 5 degrees and 10 degrees angle. Using an optimal insertion angle (0 degrees ), failure load was 1480 +/- 390 N, with 5 degrees axis deviation 780 +/- 160 N, P = 0.0001, and with 10 degrees axis deviation 550 +/- 110 N, P = 0.0001. Screws inserted in the combined locking hole (LCP) also showed a significant decrease of push-out force of 77% (4960 +/- 1000 N versus 1120 +/- 400 N) with 10 degrees axis deviation. Compared to optimal insertion angle (0 degrees ), bending load to failure did decrease up to 69% (1240 +/- 210 N vs. 390 +/- 100 N) with 10 degrees axis deviation. CONCLUSION: A locking head screw exhibits high stability with a moderate axis deviation in the angle of insertion of up to 5 degrees . However, there is a significant decrease in stability with increasing axis deviation (>5 degrees ). An aiming device is recommended to provide optimal fixation with angular stability.

Bone Screws↗
PubMed2004

Age estimation of unidentified corpses by measurement of root translucency.

To evaluate the root dentine translucency technique for age analysis, age estimates carried out at the Institute of Legal Medicine at the Charité University Hospital in Berlin between 1998 and 2002 of unidentified corpses were subjected to retrospective review. Teeth suitable for evaluation were obtained from 33 corpses of undisputed identity. Root translucency was measured at intervals of half a millimetre. Appropriate reference studies were used to translate the measurements obtained into estimated age. In 18 cases these estimates proved correct. In 14 cases the deviation lay within +/-10 years. In one case of known drug abuse combined with diabetic metabolism, two factors which promote the advance of root translucency, the deviation was 12 years. It was concluded that the described technique, which requires little time and money and is easy to apply, can produce sound results in the middle age group (30-60). To avoid seriously inaccurate estimates in individual cases, the result should always be verified critically against an assessment of the overall stomatognathic system and other post-mortem findings of relevance to age.

Adult↗
PubMed2003

Forensic age diagnostics of living individuals in criminal proceedings.

Age estimations of living individuals are increasingly important in criminal matters. If doubts arise regarding the age of a person suspected of a criminal offense, forensic age estimation is prompted by the need to ascertain whether the person concerned has reached the age of criminal responsibility and whether general criminal law in force for older juveniles or adults is to be applied. According to the recommendations of the Arbeitsgemeinschaft für Forensische Altersdiagnostik (study group for forensic age diagnostics), age estimates in criminal proceedings should be based on the general physical examination, the X-ray examination of the hand and the odontological examination by a dentist, including dental status and orthopantomogram. In order to improve diagnostic reliability, these methods should always be used in combination, ensuring that each part is performed by forensically trained and experienced experts of the relevant disciplines. In order to demonstrate that the proband has reached the age of 21, an additional X-ray examination or CT scan of the clavicles is recommended. Future research projects should assess the variation for a combination of the above methods, quantify the impact of socio-economic status and ethnicity on the examined development systems and review the suitability of non-ionizing imaging methods of age estimation.

Adolescent↗
PubMed2001

Female suicides in Berlin with the use of firearms.

The Statistical Office of Berlin recorded a total of 5488 suicides within the 10-year period 1990-1999 (3550 males, 1938 females). Firearms were used in 238 cases (218 males, 20 females). An autopsy was performed in 19 of the 20 female cases. The women's ages ranged from 21 to 88 years. Their marital status was single (n=6), married (n=5), divorced (n=5) and widowed (n=3). Eight of the women had one or more children. A suicide note was found in eight cases; six women had a history of psychiatric illness, and six had previously attempted suicide. Predominant among the suicide motives were mental (n=5) and organic (n=4) disorders as well as relationship problems (n=3) and financial difficulties (n=2). Most of the women (n=16) committed suicide in their own apartment, mainly in the bedroom. The weapons used were pistol (n=10), revolver (n=6), rifle (n=2) and a blank cartridge gun (n=1). In 16 cases we found a contact discharge at point blank range. Six of the dead women were found with the weapon still in their hands. The site of bullet-entry was the right temple (n=11), high-parietal (n=2), mouth (n=3), neck (n=1), and chest (n=2). A comparison of our results with the data of other authors for male or predominantly male collectives did not indicate any sex-specific differences regarding the type of weapon, location of the entry wound or the scene. However, alcohol was detected at a lower frequency compared with male gunshot suicides.

Adult↗
PubMed2000

Quantitative assessment of in vivo bone regeneration consolidation in distraction osteogenesis.

We present a new method for quantitatively assessing the consolidation of bone regeneration by performing distraction osteogenesis in micropigs. We measured in vivo stiffness using a newly developed, revolving, bone-healing meter. After the micropigs were killed, we obtained maximum torsional moment data for the regenerated bones by destructive mechanical testing, and we then correlated these data with the data for stiffness. We found a highly significant regression between in vivo stiffness and maximum torsional moment (r2 = 0.80), suggesting that monitoring stiffness may be useful for the prediction of bone regeneration in distraction osteogenesis. Therefore, our method may be a reliable tool for future quantitative monitoring of healing progress in patients with healing bones or in animal studies addressing treatments to increase bone formation in long-bone defects.

Animals↗
PubMed2000

Effects of ethnicity on skeletal maturation: consequences for forensic age estimations.

An X-ray of the hand is an important method in forensic science for estimation of the age of juvenile suspects with uncertain date of birth. Relevant X-ray standards for evaluation of skeletal maturity are available for white US Americans as well as for North and Central Europeans. The applicability of these standards to members of ethnic groups different from the reference population has been the subject of controversial discussion. More than 80 publications were analysed with the view to finding out whether skeletal maturation is affected by ethnic identity. It was concluded that skeletal maturation takes place in phases which are identically defined for all ethnic groups. Time-related differences in passing those stages of skeletal maturation within the relevant age group appear to be unaffected by ethnic identity. It is the socioeconomic status of a given population which is of decisive importance to the rate of ossification. The application of X-ray standards to individuals of a socio-economic status lower than that of the reference population usually leads to underestimation of that person's age. In terms of criminal responsibility, this is of no adverse effect on the person concerned.

Adolescent↗
PubMed1999

Changes in the phenotype of polymorphic plasma proteins after liver transplantation - new data and medico-legal consequences.

The genetically inherited polymorphic plasma protein types have always been considered stable for lifetime in humans. Most of these proteins are synthetised in the liver. Phenotypes for 14 plasma proteins in donors and recipients of liver transplants prior to and after transplantation were determined in 15 patients who had undergone liver transplantation at the university hospitals Charité and Rudolf Virchow in Berlin. The plasma proteins investigated were HP, TF, GC, PI, ORM1, ITI, A2HS, PLG, FXIIIB, BF, C3, C6, C8 and FH. Evidence was provided of irreversible change from the recipient type to the donor type in at least one patient for all the systems investigated. This is the first time such data have been obtained for ITI, A2HS, C8 and FH. These results clearly support the point that the dogma of life-long stability of genetically determined protein phenotypes is merely of limited validity. Against the background of good long-term results of liver transplantation, there are consequences for the practice of legal medicine in the particular context of certification of parentage, identification and stain analysis.

Blood Proteins↗
PubMed1999

A new device to quantify regenerate torsional stiffness in distraction osteogenesis.

We present a newly developed torsional stiffness measurement device with the potential to quantitatively assess the in vivo torsional stiffness of bone regenerate during distraction osteogenesis. We describe the form and function of this device and its application in a model of regenerate consolidation. The device was able to produce data to assess stiffness of the regenerate with an accuracy between +/- 3 and +/- 9% for material stiffness ranging between 0.1 and 2.4 Nm/o and with a precision of +/- 3.6%. This method provides advantages over similar methods of bone fracture healing assessment with guaranteed maintenance of bone axis, minimized risk of bone misalignment during the bone healing process and a close relation to the functional loading pattern in torsion of bones such as tibia and femora.

Animals↗
PubMed1996

Phenotype change in polymorphic plasma proteins following liver transplantation.

In 7 patients who received liver transplants, 12 plasma proteins were subjected to phenotype analysis in donor and recipient before and after transplantation. The plasma proteins analyzed were haptoglobin, transferrin, glycoprotein GC, alpha-1-antitrypsin, complement factor 3 (C3), orosomucoid 1, properdin factor B, complement factor 6, alpha-2-HS-glycoprotein (A2HS), plasminogen, factor B of coagulation factor XIII, and interalpha-trypsin-inhibitor (ITI). Classification was done with isoelectric focusing or agarose gel electrophoresis (C3). A change from recipient to donor type was observed for all systems with the exception of C3. This is the first time such data have been obtained for the A2HS and ITI systems. The time is indicated at which the recipient type disappeared and the donor type appeared. In addition to the expected phenotype changes from recipient to donor type, unexpected results were found in some systems. For instance, in 2 patients a mixed type was synthesized, or new phenotypes appeared. Possible explanations include blood transfusions, immunosuppressive therapy, extrahepatic sites of synthesis and disturbed transplant function. The usefulness of phenotype determination as a diagnostic criterion for transplant function is discussed.

Adult↗