Factors affecting postmortem tooth loss

Unassociated human bones are a particular problem during the exhumation of mass graves and a factor that limits anthropological and paleopathological analyses from archaeological contexts. Extensive anthropological literature has focused on the complex taphonomic factors that influences bone assemblages, but little attention has been paid to postmortem tooth loss and factors affecting this process. The following study focuses upon the influence of different factors on postmortem tooth loss. Three samples were investigated in the study: a medieval church cemetery containing 110 individual skeletal remains, and two samples from a series of mass graves made within the same time period in 1999, containing 402 bodies. The frequency of postmortem tooth loss was analyzed relative to postmortem interval for each sample, excavation methods, age distribution, and presence of bone loss associated with periodontal disease. Our results indicate that the degree of alveolar bone loss significantly affected both antemortem and postmortem tooth loss and that the frequency of postmortem tooth loss has the strongest correlation to time since death. These findings suggest that additional care should be taken when exhuming remains from older contexts.     

Interindividual morphologic variability as reason for misinterpretations in forensic osteology exemplified by a rib

Bone finds make great demands on the examiner. The first priority is to establish the remains as human, because then further analyses have to be performed for identification. Especially for bone fragments it may be extremely difficult to determine whether they are of human or animal origin. In the reported case a bone fragment similar to a human rib was found in a medieval town together with more than 300 non-human bones. As it turned out, a medieval cesspit had been opened during excavation works. Even an mtDNA analysis could not answer the question whether the rib was of human origin. A direct comparison with numerous ribs of humans and mammals showed the great interindividual variability, but in the end it was possible to rule out a human origin and to identify the fragment as the third left rib of a pig.     

Guidelines for international forensic bio-archaeology monitors of mass grave exhumations

The systematic exhumation of mass graves is becoming a frequent occurrence globally. Historically, it has been mostly anthropologists with their particular expertise in osteology that have been engaged by non-governmental organizations (NGO) to monitor mass grave exhumations and postmortem examinations, conducted by a host country or international forensic team, to ensure competence and a concern for justice. The excavation of graves and examination of their contents for the purposes of personal identification of victims and/or collection of evidence for prosecution require the creation of standards that meet international concerns for forensic investigation of the highest quality. However, many anthropologists are not experienced with large sites; do not have much, if any, expertise in archaeology; and are not equipped by training to assess the quality of a forensic pathologist's autopsy. This contribution is directed to both the NGO and the bio-archaeologist who are involved in the exhumation of mass graves. The experience and skills appropriate for the bio-archaeological monitor are outlined; similarly, the policies and standard operating procedures (SOP's) of the NGO that will enable the bio-archaeologist to perform their task are detailed. It is becoming increasingly clear that how a grave site was created, filled, and concealed, along with subsequent processes of site formation (e.g. slumping, robbing, animal scavenging and taphonomic alteration), require the expertise of a forensic archaeologist to discover and record site complexity along with associated forensic evidence. Similarly, the bodies themselves which are often skeletonized, fragmented and commingled pose challenges for the anthropologists and pathologists whose postmortem examinations must be critically evaluated. A model protocol for observations to make at the site as well as at the mortuary facility is provided to guide the monitor and to provide a structure for reports which are of standardized content suitable for international agencies concerned with mass grave investigation.     

A clandestine burial in Costa Rica: prospection and excavation

Abstract:  This case report describes the search for a clandestine grave in Costa Rica for which the police sought the assistance of an archaeologist. An anonymous informant suggested that the victim had been kidnapped and murdered, placed in a shallow grave in the woods, then covered with lime and cement. A search of the area to detect conventional signs of burial (e.g., slumping, different plant growth) resulted in excavation of unrelated features of past disturbance. Different aspects of the grave including the deposition of cement powder over the body prevented its initial discovery. Improvisation of conventional archaeological excavation methods and use of police familiar with archaeological excavation resulted in the location of the grave and exhumation of the victim without loss of important contextual evidence that supported testimony on the cause of death. The taphonomic effects of high-lying ground water and lime in the tropical burial environment are briefly discussed. Recommendations such as the construction of a temporary sump to lower the ground water level in the grave during excavation are made to assist in similar investigations in the future.     

The "coffin fly"Conicera tibialis (Diptera: Phoridae) breeding on buried human remains after a postmortem interval of 18 years

The "coffin fly,"Conicera tibialis Schmitz (Order: Diptera, Family: Phoridae), is well known for its frequent occurrence on buried corpses, in some cases after postmortem intervals of even 3-5 years. The present report describes the presence of a large amount of individuals of C. tibialis inside the coffin of a buried human corpse exhumed 18 years after death in central Spain. Adults, some of them newly emerged, and empty puparia were found in connection with the remains. Such postmortem interval is significantly longer than previously known for this species and raises the question on the current state of knowledge about the use of insects for estimating the postmortem interval in old, buried remains.     

Bones, blood, pellets, glass, and no body.

A man was found guilty of killing his wife, although her body was never found. The case centered on her car, which contained fragments of bone, glass, shotgun pellets, and dried blood. Deoxyribonucleic acid (DNA) fingerprinting techniques were used to establish the decedent's identity. Examination of the bone fragments revealed that they were from the skull. These two pieces of information, added to other evidence, proved that the defendant's wife had received a fatal injury in her car, and a guilty verdict was rendered.     

Storage of Second World War bone samples: Bone fragments versus bone powder

Bone samples may yield low-quality and low-quantity DNA and duplicated analyses of different genetic markers have to be performed for identification of missing persons. Mostly no DNA extract is left after analyses and efficient storage of bones is needed to ensure the stability of the sample over time for retesting using new markers and new technologies. Usually not all of the bone powder prepared in grinder is used for extraction and rest can be stored for future analyses. After molecular genetic analyses of 88 victims of Second World War (WWII) Konfin I mass grave in Slovenia (performed in 2009), fragments of femurs and bone powder that were left were stored at -20 °C. Some authors reported that long-term storage of powder results in the reduction of DNA preservation and its degradation (even at low temperature), explained by an increase in oxidative damage as a result of the enormous increase in exposed surface area. Consequently, grinding of bones as shortly prior to DNA extraction was recommended. The goal of our study was to explore the difference in DNA yield between bone fragment and bone powder frozen for 10 years. 57 WWII femurs were examined and DNA extracted from each of them using bone fragment (piece sampled next to the one used in 2009) and bone powder obtained in 2009, both taken out of freezer after 10 years of storage. Half gram of bone powder was decalcified using full demineralization extraction method. The DNA was purified in a Biorobot EZ1 (Qiagen) and quantified with PowerQuant kit (Promega). Statistical analysis showed significant difference at the 0.05 level in DNA yield comparing fragments of bones and bone powder stored at -20 °C for 10 years. The results show there is more DNA stored in the bone powder than in the bone fragments. Because of time - consuming powdering procedure we recommend to store not only the fragment of the bone, but obtained bone powder as well.     

Post-cremation taphonomy and artifact preservation

Contemporary commercial cremation is a reductive taphonomic process that represents one of the most extreme examples of postmortem human alteration of bone. The thorough reduction and fragmentation of cremated human remains often leaves little biological evidence of diagnostic value. Instead, non-osseous artifacts often provide the best evidence of the origin of the cremated remains, the identity of the decedent, and commingling of the remains of more than one individual. Once human remains have been cremated they are most commonly placed into a processor and reduced into small fragments and fine ash suitable for inurnment or scattering. The type of processor determines the size and utility of the particulates and artifacts available for analysis. The newest type of processors have changed the manner and degree of postmortem bone modification and altered the preservation of diagnostic bone fragments and cremation artifacts. This paper addresses the impact of the newest cremation procedures on forensic analysis of cremated remains.     

烧骨残片种属鉴定的研究

为了找出常见动物骨骼焚烧残片的种属鉴定方法,笔者对猪、羊,股骨及肱骨的断端,猪、羊、牛颅骨的残片(额顶部),焚烧后进行了观察及测量,并与人类股骨、肱骨及焚烧的颅骨残片进行了比较.结果发现,长骨滋养孔的位置,骨干骨壁厚度,以及颅骨厚度,颅缝形态及内板表面特征等方面,是鉴定骨骼残片种属的有价值的特征.根据对常见动物长骨及颅骨残片的现察及研究,提出了骨骼残片种属鉴定的方法.     

The Difficult Task of Assessing Perimortem and Postmortem Fractures on the Skeleton: A Blind Text on 210 Fractures of Known Origin

The distinction between perimortem and postmortem fractures is an important challenge for forensic anthropology. Such a crucial task is presently based on macro‐morphological criteria widely accepted in the scientific community. However, several limits affect these parameters which have not yet been investigated thoroughly. This study aims at highlighting the pitfalls and errors in evaluating perimortem or postmortem fractures. Two trained forensic anthropologists were asked to classify 210 fractures of known origin in four skeletons (three victims of blunt force trauma and one natural death) as perimortem, postmortem, or dubious, twice in 6 months in order to assess intraobserver error also. Results show large errors, ranging from 14.8 to 37% for perimortem fractures and from 5.5 to 14.8% for postmortem ones; more than 80% of errors concerned trabecular bone. This supports the need for more objective and reliable criteria for a correct assessment of peri‐ and postmortem bone fractures.     

Planning the archaeological recovery of evidence from recent mass graves

Mass graves commonly contain hundreds of putrefying bodies, which bear evidence of torture and extrajudicial execution. These require careful excavation using archaeological techniques to recover the bodies for identification and to obtain associated evidence which document human rights abuses. In order to derive forensically defensible conclusions, exhumation of a mass grave may take weeks or months. Specialized protective suits and breathing apparatus will permit the investigating team to take the time required to retrieve even subtle evidence from repellent remains. Strategies for sampling tissues and bodies which reduce the magnitude of the recovery operation are described.     

Interindividual variability, pathological changes and decomposition as an impediment to the morphological determination of human specificity of bone finds

Playing children discovered several teeth close to the wall surrounding a village church. A subsequent police search yielded further teeth, three neurocranial fragments, a metacarpal bone and the fragment of a long tubular bone. The circumstances along with the results of the investigation and the morphological findings suggested historical bones from a former graveyard. However, a large fragment of bone shaft from a long bone could not definitely be classified as being of human origin. The tibia of a deer was amongst the possibilities considered. Comparative tests run at the Institute of Veterinary Anatomy of the University of Giessen in addition to histological examinations, however, ultimately established the human specificity. Interindividual variability and decomoositional changes were determined as causes for the conspicuous macroscopic and microscopic findings for the tibia fragment. Pathological changes could not be demonstrated.     

Collembola of the grave: a cold case history involving arthropods 28 years after death

This report describes a cold case in which a cadaver of a 28-year-old female was exhumed in February 2005 from a cemetery in Battle Creek, Michigan. She had sustained a gunshot wound to the head and was found dead in her home on November 15, 1977. The body of the victim was subsequently embalmed and then buried at a depth of 1.8 m in an unsealed casket that was placed inside an unsealed cement vault. The exhumation yielded thousands of live specimens of a single species of the order Collembola or spring tails, Sinella (Coecobrya) tenebricosa (Entomobryidae). This species is considered to be a "tramp" species, cosmopolitan in the United States and Canada. Due to the ideal environmental conditions at the site, the population of this species underwent growth and development inside the casket for a number of years. Collected with the Collembola were large numbers of Acarina (mites) of the Family Glycyphagidae, and fly puparia, Conicera tibialis Schmitz (Order: Diptera, Family: Phoridae), also known as coffin flies. These invertebrates are sometimes mentioned by forensic investigators as occurring on corpses in graves, but aspects of their life history are rarely described. The species of Collembola that was found surviving and reproducing on this corpse in a casket exhumed after 28 years was the oldest reported grave site occurrence for any collembolan species based on a survey of the literature back to 1898.     

A single fatal penetrating chest wound caused by a dagger-shaped fragment of broken door glass

A 19-year-old woman ran against a glass door, and, breaking it, was struck in the left anterior chest by a single dagger-like fragment of broken door glass. This fragment deeply penetrated her chest and wounded the anterior wall of the left ventricle of her heart. She rapidly died from loss of blood. The majority of single fatal penetrating chest wounds seen at postmortem examinations are caused by firearms and bladed weapons. While penetrating chest wounds occasionally result from fragments of glass, most severe and fatal wounds from glass result from one's falling into or through plate glass and sustaining wounds of the head, face, abdomen, or extremities. A single fatal wound from a dagger-shaped piece of glass is distinctly uncommon. To prevent such an accident from occurring, safety glass must be used in front doors of public institutions.     

Discrimination between human and animal DNA: application of a duplex polymerase chain reaction to forensic identification

Identification of a report's species is one of the basic analyses in forensic laboratories. The authors report the case of 6 bone fragments recovered in a wooded area, which were not attributable to 1 animal species on the basis of morphologic examination. The aim of this study was to develop a duplex polymerase chain reaction (PCR) to discriminate human and animal origin of bone fragments. The method is based on the PCR amplification of cytochrome b and a 16S ribosomal mitochondrial DNA fragment, which has never been tested up to now. Our protocol combines a single-round PCR with direct visualization of amplicons in agarose gel, without sequencing analysis of the PCR products. The presence of a single band (359 bp) indicates a nonhuman origin of the sample, whereas 2 bands (157 and 359 bp) indicate a human biologic sample.This method revealed to be useful for forensic purposes because the 16S ribosomal mitochondrial DNA is a small human-specific fragment that is easily amplifiable even with degraded DNA from biologic materials such as old bones.     

Keeping the pieces together: comparison of mass grave excavation methodology

Mass graves are a complex and confusing mix of bodies, body parts, soils, artifacts, and other feature evidence. Forensic investigations of these complex crime scenes should attempt to maximize the collection of evidence, which includes the mortal remains, in their best possible condition as they were deposited within the graves. Two standard methods of mass grave excavation were examined with the aim of identifying the better approach. Two experienced teams using different methodologies excavated two separate but very comparable mass graves located in the same area. Single disarticulated skeletal elements not associated with a body at the time of removal from the grave were categorized and their counts analyzed to evaluate the efficiency of the differing excavation methodologies. The methodologies used were the 'pedestal' method, which focuses on the body mass, and the 'stratigraphic' method, in which the grave feature and contents are conjointly excavated. The first grave (Grave A), excavated using the 'pedestal' method, was observed to have a disproportionately larger amount of unassociated bones than did the second (Grave B), which used the 'stratigraphic' method. Chi-square (chi2) goodness-of-fit and contingency tests were performed on the total numbers of recorded elements and different categorical groups of bones, based on size and shape, in each grave. Results demonstrate that significantly greater numbers of unassociated elements resulted from the excavation of Grave A using the pedestal method, both in total number of disarticulated bones as well as within 'large' and 'medium' categories. Conversely 'small' skeletal elements were recovered at a higher rate in Grave B. The lower 'large' and 'medium' bone production rates from Grave B indicate that the stratigraphic method better maintained the provenience and articulation of remains than did Grave A, while the higher 'small' bone recovery rate may point to better recovery techniques of Grave B's excavation team.     

Recovery of human skeletal elements from a recent UK murder inquiry: preservational signatures.

Factors that control bone preservation are not fully understood but generally include those that reflect "natural" taphonomic or diagenetic processes and also those reflecting anthropogenic activity. The aim of this paper is to examine whether the survival of skeletal elements from a recent UK serial murder investigation (n = 12) and three archaeological cemetery sites from England (n = 112, 95, 182; Roman to early-medieval), share a similar recovery signature. Examination of this data demonstrates that even when clear evidence of traumatic and perimortem dismemberment exists within an assemblage, the distribution of missing elements can be almost identical to archaeological material buried in normal attrition cemeteries. Given that these preservational signatures are so similar, it is concluded that careful observation of bone surfaces is necessary to confidently interpret bone loss, particularly where dismemberment and/or element excision is suggested by the non-anatomical position of the skeleton within the grave. Where postmortem excision of bone is suspected, careful examination of contiguous bone surfaces, both macroscopic and microscopic, is suggested to detect fine cutmark lesions indicative of anthropogenic excision. Without this evidence other preservational factors must be considered both taphonomic and diagenetic.     

Role of preoperative 3-dimensional computed tomography reconstruction in depressed skull fractures treated with craniectomy: a case report of forensic interest

Patients affected by cranial trauma with depressed skull fractures and increased intracranial pressure generally undergo neurosurgical intervention. Because craniotomy and craniectomy remove skull fragments and generate new fracture lines, they complicate forensic examination and sometimes prevent a clear identification of skull fracture etiology. A 3-dimensional reconstruction based on preoperative computed tomography (CT) scans, giving a picture of the injuries before surgical intervention, can help the forensic examiner in identifying skull fracture origin and the means of production.We report the case of a 41-year-old-man presenting at the emergency department with a depressed skull fracture at the vertex and bilateral subdural hemorrhage. The patient underwent 2 neurosurgical interventions (craniotomy and craniectomy) but died after 40 days of hospitalization in an intensive care unit. At autopsy, the absence of various bone fragments did not allow us to establish if the skull had been stricken by a blunt object or had hit the ground with high kinetic energy. To analyze bone injuries before craniectomy, a 3-dimensional CT reconstruction based on preoperative scans was performed. A comparative analysis between autoptic and radiological data allowed us to differentiate surgical from traumatic injuries. Moreover, based on the shape and size of the depressed skull fracture (measured from the CT reformations), we inferred that the man had been stricken by a cylindric blunt object with a diameter of about 3 cm.     

The death of Adolf Hitler--forensic aspects

The death of Adolf Hitler is one of the unsolved mysteries of the twentieth century. Numerous historians and journalists have attempted to piece together the details, but despite the interest in the forensic literature regarding the identification of the body, there has not been much scientific debate about the alleged cause of death--cyanide poisoning, gunshot injury, or both. The available literature concerning Hitler's cause of death is incomplete because the toxicological analysis has not been performed and because the skull bone fragment with a gunshot wound possibly from Hitler's corpse has not been properly examined. This has given basis for various theories, which are reviewed. We believe that mtDNA analysis of the skull fragments and of Hitler's jaw, now filed in Moscow, and samples from maternal relatives of Hitler are crucial linking the skull fragment with the gunshot wound to Hitler.     

Ground penetrating radar surveys to locate 1918 Spanish flu victims in permafrost

The "Spanish Flu" killed over 40 million people worldwide in 1918. Archival records helped us identify seven men who died of influenza in 1918 and were interred in Longyearbyen, Svalbard, Norway, 1,300 km from the North Pole. Ground Penetrating Radar (GPR) was used successfully, in a high-resolution field survey mode, to locate a large excavation with seven coffins, near the existing seven grave markers. The GPR indicated that the ground was disturbed to 2 m depth and was frozen below 1 m. Subsequent excavation showed that: a) the GPR located the position of the graves accurately, b) the coffins were buried less than 1 m deep, and c) that the frozen ground was 1.2 m deep where the coffins were located. The GPR assisted in planning the exhumation, safely and economically, under the high degree of containment required. Virologic and bacteriologic investigations on recovered tissues may give us an opportunity to isolate and identify the micro-organisms involved in the 1918 influenza and expand our knowledge on the pathogenesis of influenza.