Odontological identification of fire victims--potentialities and limitations

An overview of the heat-induced changes of the chemical composition of bone from fresh to calcined

When bone is exposed to thermal stress, the chemical composition changes. This affects bone tissue regeneration after surgery, and these changes can also aid in reconstructing ante-, peri-, and post-mortem events in forensic investigations and past activities on cremation practices in archaeology. However, to date, no complete overview exists on the chemical composition of both fresh and thermally altered bone. Therefore, we aimed (i) to present the chemical composition of fresh bone and (ii) to present an overview of heat-induced chemical changes in bone under both reducing and oxidizing conditions. From the overview, it became clear that some chemical changes occur at a consistent temperature, independent of exposure duration, meaning there is a temperature threshold. However, the occurrence of other chemical changes appeared to be more inter-experimentally variable, and therefore, it is recommended to further investigate these changes.

Applications of contemporary artificial intelligence technology in forensic odontology as primary forensic identifier: A scoping review

Background

Forensic odontology may require a visual or clinical method during identification. Sometimes it may require forensic experts to refer to the existing technique to identify individuals, for example, by using the atlas to estimate the dental age. However, the existing technology can be a complicated procedure for a large-scale incident requiring a more significant number of forensic identifications, particularly during mass disasters. This has driven many experts to perform automation in their current practice to improve efficiency.

Objective

This article aims to evaluate current artificial intelligence applications and discuss their performance concerning the algorithm architecture used in forensic odontology.

Methods

This study summarizes the findings of 28 research papers published between 2010 and June 2022 using the Arksey and O'Malley framework, updated by the Joanna Briggs Institute Framework for Scoping Reviews methodology, highlighting the research trend of artificial intelligence technology in forensic odontology. In addition, a literature search was conducted on Web of Science (WoS), Scopus, Google Scholar, and PubMed, and the results were evaluated based on their content and significance.

Results

The potential application of artificial intelligence technology in forensic odontology can be categorized into four: (1) human bite marks, (2) sex determination, (3) age estimation, and (4) dental comparison. This powerful tool can solve humanity's problems by giving an adequate number of datasets, the appropriate implementation of algorithm architecture, and the proper assignment of hyperparameters that enable the model to perform the prediction at a very high level of performance.

Conclusion

The reviewed articles demonstrate that machine learning techniques are reliable for studies involving continuous features such as morphometric parameters. However, machine learning models do not strictly require large training datasets to produce promising results. In contrast, deep learning enables the processing of unstructured data, such as medical images, which require large volumes of data. Occasionally, transfer learning was used to overcome the limitation of data. In the meantime, this method's capacity to automatically learn task-specific feature representations has made it a significant success in forensic odontology.

Automatic detection of teeth and dental treatment patterns on dental panoramic radiographs using deep neural networks

Disaster victim identification issues are especially critical and urgent after a large-scale disaster. The aim of this study was to suggest an automatic detection of natural teeth and dental treatment patterns based on dental panoramic radiographs (DPRs) using deep learning to promote its applicability as human identifiers. A total of 1 638 DPRs, of which the chronological age ranged from 20 to 49 years old, were collected from January 2000 to November 2020. This dataset consisted of natural teeth, prostheses, teeth with root canal treatment, and implants. The detection of natural teeth and dental treatment patterns including the identification of teeth number was done with a pre-trained object detection network which was a convolutional neural network modified by EfficientDet-D3. The objective metrics for the average precision were 99.1% for natural teeth, 80.6% for prostheses, 81.2% for treated root canals, and 96.8% for implants, respectively. The values for the average recall were 99.6%, 84.3%, 89.2%, and 98.1%, in the same order, respectively. This study showed outstanding performance of convolutional neural network using dental panoramic radiographs in automatically identifying teeth number and detecting natural teeth, prostheses, treated root canals, and implants.

It is useful to use dental panoramic radiographs to perform the disaster victim identification (DVI).

Dignified Management of the Dead from Humanitarian Forensic Odontology Perspective: A Need for the National and State Level Scientific Disaster Victim Identification Teams in India

Disasters are always unpredictable irrespective of their origin. The loss of human lives is a common outcome of disasters. Along with the physical and emotional trauma sustained by the victims, there is the additional responsibility of handling the deceased. Though there is an exclusive component with the management of the dead in place the specific issue about identifying them is still a complex process. Humanitarian forensics especially involves handling, identifying and disposing the dead bodies. It requires the application of the principles of forensic sciences in a multidisciplinary way. The role of forensic odontologists and anthropologists is not only restricted to the scientific collection of dental data from the dead body but also the proper utilization of the antemortem dental data to successfully establish the identity of the deceased, either alone or combined with secondary characteristics. Elaborate and comprehensive information with justification on the role of dental data and forensic odontologists in the dignified management of the dead need to be highlighted to the Disaster Management authorities. Several International organizations have pointed out the importance of odontology features in human identification. Moreover, forensic odontologists and general dentists are also involved in the international disaster victim identification teams. The present article provides basic knowledge on disaster risk management and the institutional framework in Disaster Management and also highlights the role of forensic odontology in disaster victim identification. It calls for national and state disaster victim identification teams with the involvement of forensic odontologists.

R. V, Mony V. Histomorphologic and Gravimetric Changes of Teeth Exposed to High Temperature - <i>In vitro</i> Study

Background: In forensic dentistry, odontologists have been particularly interested in the investigation of burnt human remains. The purpose of our research is to provide morphological, stereomicroscopic, histological, and gravimetric findings from the investigation of the effects of thermal processes on teeth.Teeth, being the hardest substance in the body, give valuable information for forensic analysis. Objective: Histomorphology and gravimetric changes in teeth exposed to different ranges of high temperatures. Methodology: Thirty-six mandibular premolar teeth extracted for therapeutic purpose were taken and exposed to the varying higher temperatures. Macroscopic, stereomicroscopic, histological analyses along with the dry weight estimation were recorded at each temperature gradient. Results: From a lower temperature to a higher temperature, the specific colour change of the tooth was yellowish-orange, metallic black bronze and chalky white. Stereo microscopically, we observed intact teeth at 100°C; the gradual formation of micro cracks, crown-enamel separations from the cervical margin, eggshell cracking at 500°C; and a completely shattered crown at 900°C. Decalcified sections show dilation in the dentinal tubular pattern at 300°C. Loss of typical architecture was noted at 400°C, with dentinal tubules exhibiting the vapor bubble appearance. In-ground section alterations on the scalloping nature of dentino enamel junction, coalescing radicular dentinal tubules and sand cracking appearance of the tooth were noted at 100°C, 300°C and 900°C, respectively. Significant reductions in the weight of the teeth samples were observed with higher temperatures. Conclusion: Incineration-induced morphologic, histologic, and gravimetric alterations may provide useful information regarding the temperature and duration of fire exposure. It might also assist in understanding the conditions of the fire.

Determining the effective number and surfaces of teeth for forensic dental identification through the 3D point cloud data analysis

Background

The assimilation between three-dimensional (3D) imaging techniques and dental forensic science can provide rich and stable information for human identification. This study aimed to determine the effective number and surfaces of teeth for dental identification through the 3D imaging approach.

Material and methods

In the present study, maxillary dental casts were fabricated from subjects who met the inclusion criteria and scanned using a 3D scanner Vivid 910. Rapidform XOS/SCAN software was used to create and trim the 3D point cloud data. Subsequently, two types of 3D surface data of dental casts were registered and the root mean square errors (RMSEs) between subjects were calculated using iterative closest point (ICP) algorithm in MATLAB. Two sets of experiments with 120 combinations of the superimposed 3D dataset were designed, termed as experiments 1 and 2.

Results

In experiment 1, the difference between subjects was clearly distinguished with a minimum of six teeth of the dental arch. The results of experiment 2 suggest that the labial surfaces of the anterior teeth are sufficient to be used for dental identification.

Conclusion

Through these experiments for all possible pairs of subjects, a clear difference was observed in the RMSE between the genuine and imposter pairs. These results indicate the potential of using the 3D imaging technique to achieve highly accurate human identification. It is suggested that a future study with a larger sample number will evaluate the robustness and accuracy of this method.

The role of forensic anthropology in disaster victim identification (DVI): recent developments and future prospects

Forensic anthropological knowledge has been used in disaster victim identification (DVI) for over a century, but over the past decades, there have been a number of disaster events which have seen an increasing role for the forensic anthropologist. The experiences gained from some of the latest DVI operations have provided valuable lessons that have had an effect on the role and perceived value of the forensic anthropologist as part of the team managing the DVI process. This paper provides an overview of the ways in which forensic anthropologists may contribute to DVI with emphasis on how recent experiences and developments in forensic anthropology have augmented these contributions. Consequently, this paper reviews the value of forensic anthropological expertise at the disaster scene and in the mortuary, and discusses the way in which forensic anthropologists may use imaging in DVI efforts. Tissue-sampling strategies for DNA analysis, especially in the case of disasters with a large amount of fragmented remains, are also discussed. Additionally, consideration is given to the identification of survivors; the statistical basis of identification; the challenges related to some specific disaster scenarios; and education and training. Although forensic anthropologists can play a valuable role in different phases of a DVI operation, they never practice in isolation. The DVI process requires a multidisciplinary approach and, therefore, has a close collaboration with a range of forensic specialists.

Manner of Death Determination in Fire Fatalities: 5-Year Autopsy Data of Istanbul City

Death resulting from burns is an important social problem and a frequent accident. However, because approximately 10% of cases are estimated to result from a fire that was deliberately started, all fire-related deaths should be treated as suspicious, and the cause of a fire should be investigated. For the bodies recovered from the scene of a fire, the manner of death could also be suicide or homicide. The objective of this study was to contribute to the clarification of controversial data present in the literature on the manner of death determination of fire-related deaths, through evaluation of autopsy findings of bodies recovered from fires. We reviewed 20,135 autopsies performed in a 5-year period, in Istanbul, as the whole autopsy data of the city and found 133 fire-related deaths. The death scene investigation reports and other judicial documents, autopsy findings, and toxicological analysis results were evaluated to determine the parameters of age, sex, level of the burn, vital signs [red flare; soot in the lower respiratory tract, esophagus, and/or stomach; and screening of carboxyhemoglobin (COHb) levels in the blood], toxicological substances, presence of accelerants, cause of death, and manner of death. The manner of death was determined to be an accident in 98 (73.7%) and homicide in 12 (9%) cases, whereas there was no suicide. In addition, it could not be determined in 23 (17.2%) cases. In accidental deaths, the most frequent cause of death was COHb poisoning with statistically significant blood COHb levels greater than 10%. Further, the presence of soot in the lower respiratory tract, esophagus, and/or stomach and the existence of at least 1 or 2 vital signs together were found to be valid deterministic criteria with statistical significance in terms of identifying the manner of death.

Prosthodontics an "arsenal" in forensic dentistry

After major disasters such as earthquakes, fires, floods, tsunami, bomb blasts or terrorist attacks, accurate, and early identification of the dead and injured becomes an utmost importance. Restorations, cariesteeth, missingteeth and/or prostheses are most useful aids for the dental identification. At times, only identifiable remains are a victim's partial or complete dentures. The central principle of dental identification is that postmortem dental remains can be compared with antemortem dental records which include, studycasts, radiographs, etc., to confirm the identity of the victims. Marking/labeling dentures have been considered an important aid in forensic dentistry. Other than finger printing, when compared with all the methods, the marking/labeling of dentures is an accurate and rapid method to identify the unknown victims. There are no standardized methods to follow, but dental practitioners needs to maintain some dental records of their patients. This may include documentation of the "marking of dentures." The preparedness is the key to success in mass disaster identification. The aim of this review article is to discuss the methods of denture identification, advantages of denture labeling for the rapid identification during major disasters/accidents and the importance of maintaining the patient records.

Behavior in vitro of the dentin-enamel junction in human premolars submitted to high temperatures: prediction of the maximum temperature based on logistic regression analysis

OBJECTIVE

The aim of the study was to provide scientific evidence that would permit DEJ separation to be used as a parameter to estimate the temperature to which burnt, carbonized or incinerated cadavers or human remains had been subjected.

MATERIALS AND METHODS

A descriptive pseudo-experimental study was carried out in vitro using cone beam tomography to determine the physical behavior of the dentine-enamel junction in 60 human premolars submitted to high temperatures (200°C, 400°C, 600°C, 800°C and 1000°C).

RESULTS

Spearman's concordance and correlation index was used to determine the relationship between longitudinal separation of the dentine-enamel junction (mm) and temperature (°C) and a simple linear regression model developed to show that once micro- and macrostructural changes are initiated in the enamel and dentine.

CONCLUSIONS

The dentine-enamel junction begins to separate from the cervical towards the occlusal as temperature increases.

Contribution of the computed tomography of the anatomical aspects of the sphenoid sinuses to forensic identification

INTRODUCTION

Body identification is the cornerstone of forensic investigation. It can be performed using radiographic techniques, if antemortem images are available. This study was designed to assess the value of visual comparison of the computed tomography (CT) anatomical aspects of the sphenoid sinuses, in forensic individual identification, especially if antemortem dental records, fingerprints or DNA samples are not available.

MATERIAL AND METHODS

This retrospective work took place in a French university hospital. The supervisor of this study randomly selected from the picture archiving and communication system (PACS), 58 patients who underwent one (16 patients) or two (42 patients) head CT in various neurological contexts. To avoid bias, those studies were prepared (anonymized, and all the head structures but the sphenoid sinuses were excluded), and used to constitute two working lists of 50 (42+8) CT studies of the sphenoid sinuses. An anatomical classification system of the sphenoid sinuses anatomical variations was created based on the anatomical and surgical literature. In these two working lists, three blinded readers had to identify, using the anatomical system and subjective visual comparison, 42 pairs of matched studies, and 16 unmatched studies. Readers were blinded from the exact numbers of matching studies.

RESULTS

Each reader correctly identified the 42 pairs of CT with a concordance of 100% [97.5% confidence interval: 91-100%], and the 16 unmatched CT with a concordance of 100% [97.5% confidence interval: 79-100%]. Overall accuracy was 100%.

CONCLUSION

Our study shows that establishing the anatomical concordance of the sphenoid sinuses by visual comparison could be used in personal identification. This easy method, based on a frequently and increasingly prescribed exam, still needs to be assessed on a postmortem cohort.

Human identification using dental techniques: A case report

Dental identification of skeletal remains frequently relies on data comparison. Comparative dental identification is used to establish with a high degree of certainty that the remains of a corpse and a person represented by ante-mortem dental records are the same individual. There is no minimum number of concordant points necessary to perform a positive identification; rather, each case is unique and should be treated as such. In this paper, we present a report of a case in which positive identification was made by a paramolar tubercle in both upper first deciduous molars.

Applicability of Berry's index in bite mark analysis

OBJECTIVES

This study attempts to highlight the usefulness of applying Berry's Index as an adjuvant to support and aid in bite analysis.

MATERIALS AND METHODS

This study was conducted among 100 students between the ages of 18-30 from Mar Baselios Dental Collage, Kothamangalam. Out of the 100 subjects, there were 50 males and 50 females. The data obtained was tabulated and analyzed using Statistical Package for Social Sciences, Version 16 (SPSS).

RESULTS

The mean value of the width of the upper central incisor for male and female was 0.7602 cm and 0.7765 cm respectively. The mean value of the bizygomatic width for male and female was 12.54 cm and 12.42 cm respectively. The correlation between the upper central incisor width and the bizygomatic width was inferred to have a good positive correlation with a value 0f 0.613. Pearson correlation coefficient with greater correlation between the upper central incisor width and the bizygomatic width in female patient (r = 0.678) compared with male patient (r = 0. 525).

CONCLUSION

Berry's Index can be a useful adjuvant to bite analysis by providing a means of determining the facial proportions of an individual from the width of the central incisors.

Volume analysis of heat-induced cracks in human molars: A preliminary study

Context:

Only a few methods have been published dealing with the visualization of heat-induced cracks inside bones and teeth.

Aims:

As a novel approach this study used nondestructive X-ray microtomography (micro-CT) for volume analysis of heat-induced cracks to observe the reaction of human molars to various levels of thermal stress.

Materials and Methods:

Eighteen clinically extracted third molars were rehydrated and burned under controlled temperatures (400, 650, and 800°C) using an electric furnace adjusted with a 25°C increase/min. The subsequent high-resolution scans (voxel-size 17.7 μm) were made with a compact micro-CT scanner (SkyScan 1174). In total, 14 scans were automatically segmented with Definiens XD Developer 1.2 and three-dimensional (3D) models were computed with Visage Imaging Amira 5.2.2. The results of the automated segmentation were analyzed with an analysis of variance (ANOVA) and uncorrected post hoc least significant difference (LSD) tests using Statistical Package for Social Sciences (SPSS) 17. A probability level of P < 0.05 was used as an index of statistical significance.

Results:

A temperature-dependent increase of heat-induced cracks was observed between the three temperature groups (P < 0.05, ANOVA post hoc LSD). In addition, the distributions and shape of the heat-induced changes could be classified using the computed 3D models.

Conclusion:

The macroscopic heat-induced changes observed in this preliminary study correspond with previous observations of unrestored human teeth, yet the current observations also take into account the entire microscopic 3D expansions of heat-induced cracks within the dental hard tissues. Using the same experimental conditions proposed in the literature, this study confirms previous results, adds new observations, and offers new perspectives in the investigation of forensic evidence.

Assessment of the uniqueness of human dentition

Comparing ante-mortem and post-mortem dental characteristics has been a reliable, accurate and quick human identification method. This is based on the assumption that each individual's set of teeth is unique; however, there is little evidence to support this assumption. This research aimed to determine the uniqueness of basic dental features in a cohort of multinational dental patients. Dental charts were retrieved from the archives of the College of Dentistry at the University of Sharjah. Dental patterns were coded into letters representing basic dental characteristics, and entered into a computer program that was written specifically for analysing the results of this research. Two thousand dental charts were included in this research; the average age of the sample was 31.9 years (11-87 years). The male:female ratio was 1.4:1 from 55 nationalities. One thousand one hundred and fifty-nine dental charts (57.95%) had absolutely unique dental patterns. The remaining charts (n=841 [42.05%]) were found to have identical patterns with others, the most common of which was 'all virgin' teeth (n=482 [24.1%]). Introducing a single dental modification dropped this percentage to 1.05%. This percentage was further narrowed down to 0.7% when the gender variable was introduced to the comparison. The results of this research support the assumption that dental characteristics show a diversity that is useful for human identification, even when those characteristics are recorded in their simplest forms.

Maximizing postmortem oral-facial data to assist identification following severe incineration

PURPOSE

This paper reviews the literature for methods of maximizing the postmortem oral-facial information available for a comparison to be made for identification following an incident resulting in incineration.

METHOD

A search was initially instigated utilizing PubMed, Scopus, and Google Scholar, with further library searches and correspondences among peers around the world leading to a comprehensive review of the literature.

CONCLUSION

Maximizing postmortem dental evidence in a severe incineration event requires correct recognition and recording of dental data. Odontologists should attend the scene to facilitate this recognition. The information should be documented, photographed, and stabilized before retrieval. Wrapping, padding, and further support of the remains during transportation to the examination mortuary will aid this process. Examination at the mortuary requires further photography, complete charting, and radiographic examination of any dental material available, as well as awareness of other possible medical evidence, to enable identification of the human remains.

Sex estimation based on deciduous and permanent dentition in a contemporary Spanish population

Sex estimation of skeletal remains with satisfactory allocation accuracy represents an essential step in reconstructing the biological profile of unknown individuals in archaeological research and forensic practice. Teeth are among the most frequently recovered physical elements of an individual that remain after death due to their hardness, durability, and resistance to postmortem insults. This study was based on the deciduous and permanent dentition of 269 individuals (150 males and 119 females) from the Granada osteological collection of identified infants, young children, and adults (Granada, Spain). Mesiodistal, buccolingual, and diagonal crown and cervical diameters of both dentitions were measured, and logistic regression analyses were performed to create equations for sex discrimination. The results show that the first and second deciduous molars and the permanent canines are the teeth with the greatest sexual dimorphism, providing percentages of correct assignment of sex between 78.1 and 93.1% in deciduous dentition and between 79.4 and 92.6% in permanent teeth, depending on the dimensions used. The results indicate that this method may be applicable as an adjunct with other accepted procedures for sex estimation when fragmentary skeletal remains are encountered in archaeological excavations and in forensic contexts.

The utility of dental patterns in forensic dentistry

The comparison of antemortem and postmortem dental patterns, which reflect a combination of dental states, can be quantified for human identification. However, the utility derived from the uniqueness of these patterns is limited by variations in oral health status related to population, age, and birth cohort. We analyzed dental pattern diversity from reference datasets that documented differences in oral health. Our analysis was based on full dentitions and partial dentitions available in forensic situations. To analyze the diversity of dental patterns, data from 3166 adults were extracted from the last 3 contemporary Spanish National Oral Health Examination Surveys, corresponding to the years 1993, 2000, and 2005. Each survey comprised 2 adult age groups (35-44 years and 65-74 years), therefore six datasets were available for our study. Our six samples showed substantial variability in oral health status (caries history) and dental code distribution, not only between age groups within the same survey year, but also between different survey years for the same age group. To test the overall diversity of dental patterns in each datasets, pairwise comparisons were performed and the total number of pattern matches was generated. We calculated total and conditional diversity (excluding individuals in whom all teeth were classified as unrestored or missing) for each forensic situation. To test the homogeneity of diversity estimates among the six datasets we used a random effect model that requires a parameter estimate together with its standard error. Total diversity values were low and heterogeneous. However, conditional diversities were high and homogeneous, which allowed all data to be pooled into a single database. Once data were pooled, high combined diversity values (above 0.99) were obtained for each forensic situation. This indicates their usefulness for forensic purposes. We conclude that the conditional diversity value derived from dental patterns is a potentially valuable tool with broad applicability for human identification.

Radiographic recognition of dental implants as an aid to identifying the deceased

This study was undertaken to determine if dental implants can be radiographically differentiated by company type to aid forensic identification of the deceased. Recognition of dental implants on intraoral radiographic images was assessed in a blind study using a radiographic examination guide to highlight differences between dental implants. Inter- and intra-examiner comparisons were conducted and a computer program (Implant Recognition System) was evaluated to see whether it improved the accuracy of implant recognition. The study found that dental implants could be radiographically differentiated by company type. The Implant Recognition System in its current form was of little benefit for radiographic assessment of dental implants for forensic odontologists. Prior knowledge of implant types, with a McNemar's statistical value of 92.9, proved to be most significant in identification.

Implantation of an RFID-tag into human molars to reduce hard forensic identification labor. Part 2: physical properties

Modifying and implanting existing RFID-tags into extracted human molars was described previously [P. Thevissen, G. Poelman, B. Puers, M. De Cooman, G. Willems, Implantation of RFID-tag into human molars to reduce hard forensic identification labor. Part 1. Working principle, Forensic Sci. Int. 156 (2006)]. Maximal vertical occlusal load during which the implanted RFID-tags remain active was evaluated in vitro. The temperature dependency of the implanted RFID-tags was studied on the extracted teeth to find out the maximal obtainable temperature before failure and a test with embedded thermistors to verify temperature distributions. The maximal working temperature of the implanted RFID-tags was revealed and gave indications for the set-up of measuring intra oral and intra tooth temperature during the cremation of a human body. Fatigue was induced on the implanted teeth by thermocycling. The results of this investigation showed the need of putting an extra insulating layer around the modified tags before implantation. The different in vitro tests indicated that the implanted RFID-tags can support certain oral and forensic circumstances.

Forensic odontology lessons: multishooting incident at Port Arthur, Tasmania

On Sunday 28 April 1996 a lone gunman killed and injured many people at the historic penal settlement ruins at Port Arthur in South Eastern Tasmania, Australia. Thirty-two victims were shot dead and 19 were injured in a short time inside a cafe and along the roadway leading to the site entrance. The gunman then took one hostage to a nearby guest house which was occupied by a married couple. Police stood siege during the night. Early the next day the cottage began to burn and a man suspected to be the gunman eventually ran unarmed from the building with his clothes alight and was arrested. The house burned to the ground. Three bodies were later located in the burnt ruins. Forensic odontology played a role in the retrieval of evidence and identification of the incinerated victims. Lack of antemortem dental records for one victim necessitated the reliance on a single CT scan radiograph for matching with the remains. Fire scene procedures, evidence collection and other issues were reviewed. The overwhelming scale of this tragedy and its adverse effects on the Tasmanian community, especially the victims' families and survivors, cannot be overestimated. While acknowledging this, it is important that lessons are learnt from tragedies such as these. This paper is presented with a view to assisting forensic odontologists in the investigation of complex incidents.

Comparative study of efficiency of dental methods for identification of burn victims in two bus accidents in Spain

This article deals with the usefulness and limitations of dental identification methods of human burn victims of two buses accidents in Spain. The first accident happened in Bailen in 1996 and involved 28 badly burned Spanish victims. In the second, in Illescas in 1997, 8 Japanese and 2 Spanish victims lost their lives. In both accidents, postmortem forensic procedures for identification were used, including external and internal examination, routine photographs, and dental examination. Dental identification was established in 57% of the cases in the Bailen accident and 80% in the Illescas accident. The success rate of dental identification varies considerably depending on the nature of the accident, the nationality and country of residence of the victims, the incidence of dental treatment, the availability of adequate dental records, and the degree of dental injuries. A discussion of procedures and methods for identification recommended when dealing with burn victims is included.

A look at forensic dentistry--Part 1: The role of teeth in the determination of human identity

Forensic dentistry can be defined in many ways. One of the more elegant definitions is simply that forensic dentistry represents the overlap between the dental and the legal professions. This two-part series presents the field of forensic dentistry by outlining two of the major aspects of the profession: human identification and bite marks. This first paper examines the use of the human dentition and surrounding structures to enable the identification of found human remains. Conventional and novel techniques are presented.

Facial burns in children: a series analysis with implications for resuscitation and forensic odontology

This study comprises a continuous (1981-1995) unselected series of all children who died from thermal injuries in the State of Queensland, Australia. One hundred and six children, so identified, died from incineration (35 per cent), respiratory burns with smoke or carbon monoxide inhalation (33 per cent), body surface area burns comprising greater than 60 per cent (9 per cent) and electrocution (20 per cent). The burn fatality rate was 0.98 per hundred thousand children (0-14 years) per year, with no secular trend and, specifically, no reduction in the annual rate of such fatalities. Eighty-two children (49 males) had concomitant facial injuries, both thermal and nonthermal; of whom 55 per cent were under the age of five years. Sixty (73 per cent) child burn victims died in house fires. Forensic odontology is important in confirming the age of such victims in single incinerations but is of limited value when larger numbers of children are incinerated, because of the relative lack of dental restorations in the infant and pre-school age group. Of the 82 children with facial and airway injuries, 12 per cent had only mild or superficial facial damage and only seven (8 per cent) were alive or resuscitable at the time of rescue from the conflagration or burning injury. child deaths from burns contributed an annual loss rate of 506 years of potential life lost (YPLL) in a population of 3 million of whom 21.5 per cent were children under the age of 15 years. Airway management and resuscitation, in the context of managing surviving burn victims of any age with facial injuries, pose special difficulties. Inhalational burns (smoke and the gases of conflagration) result in a mortality greater than 60 per cent. Although 81 per cent of children showed evidence of airway obstruction, analysis of current data indicates that a maximum of 8 per cent could have survived with airway maintenance and protection. Inhalational burns (to both upper and lower airways) grossly reduce survivability. Primary prevention would seem vital and thus remains a major challenge to reduce the incidence of such deaths. Some strategies include advocacy to promote the compulsory installation of smoke alarms, family drills to practise escape and the teaching of 'first aid for all'

Individual identification by means of conventional bitewing film and subtraction radiography

An analysis of simulated post- and antemortem (p.m. and a.m.) victim radiographs was performed. Existing pairs of bitewing radiographs randomly sampled from a large population of adolescents were used. Two categories of individuals were included based on dental therapy conditions (none or few simple fillings). Subtraction images were performed of pairs of bitewings originating from the same individual (identical images) and different individuals (non-identical images) within each group. Four observers were asked to match the bitewings and to assess the subtraction images with respect to identity based on the score system: 1 = 'eliminated', 2 = 'possible', 3 = 'likely', or 4 = 'certain'. Three observers each mismatched the film radiographs among two out of 12 individuals without fillings. True positive identification (identified by scores 2 + 3 + 4) of subtraction images were made in 10-12 individuals out of a possible 12. The range of false positive (FP) and false negative (FN) scorings was 3-15 and 0-2, respectively. All observers were capable of correctly matching bitewings originating in the 12 individuals with amalgam fillings. By use of subtraction radiography, 12-14 identical images out of a possible 15 were assessed correctly. The range of FP and FN scorings of subtraction images in this group was 1-4 and 1, respectively. Defining only score 4 as positive identification, the sensitivity of the subtraction technique decreased from approximately 0.90 to 0.70 in both categories of individuals, while specificity increased to almost 1.00 from 0.82 vs. 0.96 in the categories with and without dental restorations. Bitewing radiographs from single individuals within a group of individuals were sufficiently identical to allow for valid identification by a strict criterion. The subtraction technique may add to the subjective matching of radiographs as a screening test in victim identification.

Quality evaluation of 10 years patient records in forensic odontology

In forensic odontology, accurate detailed and complete recording of ante-mortem information is essential as the basis for odontological identification. Earlier studies on malpractice cases in Sweden indicated that the quality of the recording procedure was not always acceptable. Therefore, the aim of this retrospective study was to investigate the quality of ante-mortem records and its possible implications for identification work. All forensic odontology cases referred to the Department of Forensic Medicine in Göteborg between 1983 and 1992 were studied with regard to the instructions for dental records from the National Board of Health and Welfare. Information on dental characteristics, normal anatomical findings and restorative treatment was complete in 43 (68%) of the cases, incomplete in 17 (27%) and missing in 3 (5%). Registration of previous therapy was missing in about 75 (94%) of the records. It was possible to identify patient radiographs in only 16 of the 40 records where radiographs were available. In spite of this, the inaccuracies in the records did not seem to hamper the identification procedures in this study which could be explained by the character of the cases and the availability of medical and circumstantial information.