Human Identification Through the Analysis of Smile Photographs

Post-mortem to ante-mortem facial image comparison for deceased migrant identification

The identification of deceased migrants is a global challenge that is exacerbated by migration distance, post-mortem conditions, access to ante-mortem data for comparison, inconsistent international procedures and lack of communication between arrival and origin countries. Due to low technology requirements, fast speed analysis and ease of transferring digital data, facial image comparison is particularly beneficial in those contexts, especially in challenging scenarios when this may be the only initial ante-mortem data available to identify the deceased. The Facial Identification Scientific Working Group (FISWG) professional guidelines for facial image comparison were developed for living facial appearance, and, therefore, a tailored protocol for the application of post-mortem to ante-mortem facial image comparison was proposed and evaluated in this research. The protocol was investigated via an inter-observer and an accuracy study, using 29 forensic cases (2001-2020) from the University of Milan, provided by the Laboratory of Forensic Anthropology and Odontology. In order to replicate a migrant identification scenario, each post-mortem subject was compared to all 29 ante-mortem targets (841 comparisons). The protocol guided the practitioner through stages of facial image comparison, from broad (phase 1) to more detailed (phase 3), eventually leading to a decision of 'exclusion' or 'potential match' for each post-mortem to ante-mortem case (phase 4). In phase 4, a support scale was also utilised to indicate the level of confidence in a potential match. Each post-mortem subject could be recorded with multiple potential matches. The protocol proved to be useful guide for facial image comparison, especially for less experienced practitioners and the inter-observer study suggested good reproducibility. The majority (82-96%) of ante-mortem subjects were excluded at the first stage of the protocol, and 71 full post-mortem to ante-mortem facial image comparisons were carried out. On average, two or three potential matches were recorded for each post-mortem subject. The overall accuracy rate was 85%, with the majority (79%) of ante-mortem non-targets correctly excluded from the identification process. An increased number and quality of available ante-mortem images produced more successful matches with higher levels of support. All potential matches involving non-targets received low levels of support, and for 73% of the post-mortem subjects, the ante-mortem target was the only recorded potential match. However, two ante-mortem targets were incorrectly excluded (one at the first stage of the protocol) and therefore changes to the protocol were implemented to mitigate these errors. A full protocol and a practical recording chart for practitioner use is included with this paper.

Analysis of smiling photograph; Operation US-Bangla Air Crash

Human identification may be difficult when there is no antemortem data available. A photograph of the deceased may be valuable in such cases. Digital advancement and inclusion in the lives of ordinary people makes it easier to retrieve clear, high-resolution photos from social media accounts and other places. This paper describes three cases of forensic dental identification from a US-Bangla plane crash in Nepal in which a charred body was positively identified from a smiling photograph provided by the deceased's family. Each case is unique and their identification rests on the availability of pre- and post-mortem information. Thus, the number of concordant points may vary from single to multiple; there is no defined criteria for minimum number of concordance for a positive dental identification.

Dental Radiographic/Digital Radiography Technology along with Biological Agents in Human Identification

The heavy casualties associated with mass disasters necessitate substantial resources to be managed. The unexpectedly violent nature of such occurrences usually remains a problematic amount of victims that urgently require to be identified by a reliable and economical method. Conventional identification methods are inefficient in many cases such as plane crashes and fire accidents that have damaged the macrobiometric features such as fingerprints or faces. An appropriate recognition method for such cases should use features more resistant to destruction. Forensic dentistry provides the most appropriate available method for the successful identification of victims using careful techniques and precise data interpretation. Since bones and teeth are the most persistent parts of the demolished bodies in sudden mass disasters, scanning and radiographs are unrepeatable parts of forensic dentistry. Forensic dentistry as a scientific method of human remain identification has been considerably referred to be efficient in disasters. Forensic dentistry can be used for either "sex and age estimation," "Medical biotechnology techniques," or "identification with dental records," etc. The present review is aimed at discussing the development and implementation of forensic dentistry methods for human identification. For this object, the literature from the last decade has been searched for the innovations in forensic dentistry for human identification based on the PubMed database.

Exploring the use of selfies in human identification

BACKGROUND AND AIMS

The comparison of post-mortem evidence to ante-mortem data is the usual approach Forensic Odontologists take in managing human identification cases. Although dental charts and radiographs are widely used as ante-mortem dental evidence, photographs, including non-clinical ones such as selfies are not regarded as such. Therefore, photographs are not regularly assessed in identifying the deceased. This cross-sectional study was aimed to investigate the possible contributions of selfies in human identification and to suggest a structured methodology to assess selfie images with the data collected.

MATERIAL AND METHODS

An e-survey composed of five open and seven close-ended questions was designed using JISC Online Surveys program (2020) to explore the opinions of practising Forensic Odontologists and related professionals on the use of photographs and selfies in human identification. Responses to the survey were collected and analysed into descriptive charts and statistics.

RESULTS

Eighty-two out of 200 professionals completed their responses (40.8% response rate). 73.2% of them acknowledged that selfies could be used as a main or adjunct evidence in dental identification. Experienced participants in selfies assessed dental anatomy (n = 6), dental restorations (n = 6), craniofacial landmarks (n = 5), oral soft tissues (n = 3), and implement the use of photo-editing software (n = 3) when provided with photographs to analyze using the direct comparison technique.

CONCLUSION

It may be concluded that selfies could be supplementary dental ante-mortem evidence. The designing of a step-by-step visual analysis of dental characteristics on a selfie photograph could subsequently be incorporated into official Forensic Odontology association guidelines worldwide. Further research in this area should be carried out along with the advancements in technology.

Rediscovering the value of images in supporting personal identification of missing migrants

The crisis concerning the identification of dead migrants is forcing forensic scientists to deal with the unavailability of classical antemortem (AM) data such as radiological information and DNA. However many times there is abundant AM photographic data of which the availability and quality is underestimated. Independently of when facial image comparison can be used as a valid identification method, description of the unexpected quality and quantity of images in the scenario of unidentified migrant decedents is given in this observational study. It focuses on the overall characteristics of the AM images available for a group of 74 missing migrants related to the disaster of October 3rd, 2013. 394 images were collected: an average of 6 for each missing person. 18% are original pictures, 47.5% scans of original images, 9.9% scans of printed images while 9.4% downloaded from social networks such as Facebook. 42.7% of images resulted in focus. Among all the images, about the 10% has been used in the personal identification process to ascertain the identity of 22 persons, because of the visibility of identifying details (facial, dental and body features). The importance of such a finding should not be diminished by its simplicity. Today, those involved in collecting AM information from relatives of dead migrants are underestimating the possible presence of images, even in sub-Saharan populations, where, contrary to belief and data, technology, though simple, is available and images may turn out to be abundant and useful (and at times the only resort) for identification.

Computerized delineation of the teeth and comparison with a smiling photograph: identification of a body skeletonized by cadaverous ichthyofauna action

Amazonian's forensic experts usually experience considerable difficulties in the identification of drowned bodies rescued from the rivers of the Amazon basin, since they are frequently found skeletonized by the action of the cadaverous ichthyofauna. In these circumstances, especially when the soft tissues are completely absent, bones and teeth may represent the unique source of information for the identification of the body. This work reports a case of positive identification of a body skeletonized by scavenger ichthyofauna. The identification was performed by comparing computerized delineation of the dental characteristics of the cadaver with those observed in a smiling photograph of the victim. This report also highlights the ferocity of Cetopsis candiru (candiru cobra), Cetopsis coecutiens (candiru-açu) and Calophysus macropterus (piracatinga).

The forensic value of smile photograph and medical radiograph analysis in identifying human skeletonized remains: a case report

Background

Identifying human remains which are skeletonized, carbonized, disfigured, or fragmentized is a common task for forensic anthropologists and odontologists.

Case presentation

A case of unknown skeletonized remains is reported in this investigation, which was found in a mass grave in Damascus Countryside governorate, Syria, in 2017. The post-mortem (PM) examination of bones and teeth was completed in al-Muwasat University Hospital in Damascus. Skull and pelvic bones showed Caucasoid male traits: the fourth rib and teeth examination estimated the age to be between 30 and 40 years, and the long bone estimated the stature in centimeters to be between 172 and 179. Intact dentition with tiny fracture in the incisal edge of the upper right central incisor—along with pathological fracture of right patella—was noted. Matching with ante-mortem (AM) smile photograph and radiograph of the right knee led to positive identification.

Conclusions

The present study highlights the importance of maintaining and storage of medical radiographs or any other records that show the teeth or bones of the person.

Strengthening the role of forensic anthropology in personal identification: Position statement by the Board of the Forensic Anthropology Society of Europe (FASE)

In this position statement, the Board members of the Forensic Anthropology Society of Europe (FASE) argue that forensic anthropology methods can be used as means of personal identification, particularly in situations with limited availability of traditional identification methods (i.e. dactyloscopy, odontology, and molecular genetic analysis). This statement has been issued taking into account the international migration crises related to thousands of deaths worldwide, in which the utility of these traditional means of identification has been sporadic to non-existent. The statement is however not limited to deaths related to the migration crises, as similar problems may occur in fatalities en masse such as in natural disasters and armed conflicts, and on a smaller scale in cases of homeless or otherwise socioeconomically disadvantaged persons. The number of reports on personal identification based on sound anthropological methodology is increasing in the scientific literature. However, more research is needed to develop evidence-based standard operating procedures and statistical frameworks. It remains essential to raise awareness among forensic practitioners, law enforcement, and judiciary professionals on the utility of forensic anthropology in cases where it can provide sufficient information for identification.

Dental Cingulum and Position of Fixed Orthodontic Appliance as Source of Morphological and Therapeutic Identifiers: An Unusual Case Report

Orthodontic records, such as photographs, radiographs, and dental casts, provide information useful for identification purposes because it may reveal important morphological, therapeutic, and pathological dental identifiers. Among these identifiers, the type and position of orthodontic appliances figure as distinctive tools for human identification. In this context, the present study aims to report an uncommon case of identification of a putrefied body, found near to a forest region in Brazil. The postmortem (PM) examination showed that the victim had part of a fixed orthodontic appliance installed in the maxillary and mandibular dental arches. To identify the body, relatives of the potential victim presented orthodontic examinations containing panoramic radiography and photographs of the orthodontic treatment. The body was identified based on the analysis of the radiographs and photographs that confirmed the presence of the orthodontic appliances observed PM. More specifically, the identification was supported by the analysis of bracket bonding position of the maxillary and mandibular incisors and the presence of distinctive morphological traits of the canines and incisors, as well dental roots observed radiographically. The present case highlights the importance of orthodontic records as a source of morphological dental identifiers for cases in which only unrestored teeth are available.

Case-specific characteristics of pink teeth in dental autopsies - A systematic review

The cadaveric alterations that derive from the decomposition of the human body are often investigated and examined in medical autopsies together with any other evidence of thanatological interest. This study aimed to systematically review case-specific characteristics of dental autopsies that reported the pink tooth phenomenon (PTP). The review was performed in October/2018 and followed PRISMA and Cochrane guidelines. Seven databases were searched as primary study sources (PubMed, Scopus, LILACS, SciELO, Web of Science, Science Direct and Embase) and three (OATD, Open Grey and Open Thesis) were searched for "grey literature". Only descriptive studies were collected, namely case reports and case series. The risk of bias among the studies was assessed with The Joanna Briggs Institute Critical Appraisal tool. From each case, the sex and age of the victims were registered, together with the place of body recovery, time of death, cadaveric status, cause of death, and number and position of pink teeth. Additionally, a supplemental quantitative analysis was conducted within a sampled subgroup. Poisson regression with robust variance was used to analyze relative risks of presenting pink teeth according to age and tooth position. Eleven studies out of 1004 were eligible. In total 71 cases of cadavers with pink teeth were reported. Two (2.81%) victims had unknown sex, while 17 (23.95%) were females and 52 (73.24%) were males. The victims were aged between 4 and 85 years (mean age 31.13 ± 13.32). Dental autopsies registered 331 pink teeth (163 anterior, 87 premolars and 81 molars). The age did not influence on presenting an additional pink tooth, regardless of tooth position (p > 0.05). Forensic dentists must be aware of pink teeth in dental autopsies. This is an unspecific phenomenon and must not be misinterpreted in medico-legal investigations.

Personal Identification of Deceased Persons: An Overview of the Current Methods Based on Physical Appearance

The use of the physical appearance of the deceased has become more important because the available antemortem information for comparisons may consist only of a physical description and photographs. Twenty-one articles dealing with the identification based on the physiognomic features of the human body were selected for review and were divided into four sections: (i) visual recognition, (ii) specific facial/body areas, (iii) biometrics, and (iv) dental superimposition. While opinions about the reliability of the visual recognition differ, the search showed that it has been used in mass disasters, even without testing its objectivity and reliability. Specific facial areas being explored for the identification of dead; however, their practical use is questioned, similarly to soft biometrics. The emerging dental superimposition seems to be the only standardized and successfully applied method for identification so far. More research is needed into a potential use of the individualizing features, considering that postmortem changes and technical difficulties may affect the identification.

Selfie identification app as a forensic tool for missing and unidentified persons

Social media applications can be valuable investigative tools in the search for missing and unidentified persons. As yet, no forensic App exists with the aim of assisting the human identification process, through the search of antemortem data to be used as adjunct data in the comparison with postmortem data collected. The aim of this article is to introduce a new application for Smartphones called “Selfie Forensic ID” App which will employ selfie and face photographs as an archive of dental data and dental features of the front teeth of missing persons sharing with Instagram, Tumblr, and Twitter Social Networks (available for free download from both Android and Apple store at http://onelink.to/selfieforensic). Features such as diastema rotated or wrongly positioned teeth, lip anomalies, recognizable fixed prosthetics, dental crown discolorations, dental or cutis piercing could represent strong identifiers in the comparison of AM and PM data. The increased number of terrorist attacks and natural disasters which result in the premature death of innocent people underlines the importance of storing personal identification data to avoid bodies remaining unidentified. The authors believe there will be an increased public willingness to share personal ID information through understanding of the ethical and administrative consequences to the families of deceased persons should bodies remain unidentified.