Age estimation through the development of third molars in a case of multiple dismemberment / Estimación de la edad mediante el desarrollo de terceros molares en un caso de desmembramiento múltiple

El crimen organizado se ha convertido en un flagelo a nivel internacional conformado por grupos al margen de la ley que realizan todo tipo de actividades que involucran desde tráfico de personas, secuestros, extorsiones, narcotráfico y muchos otros delitos. Producto de este fenómeno, la desaparición y ejecución de personas es cada día más frecuente, en muchos casos los cuerpos son quemados o desmembrados para impedir o hacer más difícil la identificación. La odontología forense se ha convertido en una disciplina transcendental en la identificación de cadáveres y restos óseos, además de contar con múltiples métodos para estimar la edad aproximada de una persona. Se presenta el caso de un descuartizamiento múltiple de tres individuos masculinos donde era indispensable identificar si alguno correspondía a una persona menor de 18 años.

Organized crime has become an international scourge made up of outlaw groups that carry out all kinds of activities ranging from human trafficking, kidnapping, extortion, drug trafficking and many more. As a result of this phenomenon, the disappearance and execution of people is becoming more frequent every day, in many cases the bodies are burned or dismembered to prevent or make identification more difficult. Forensic odontology has become a transcendental discipline in the identification of corpses and skeletal remains, in addition to having multiple methods to estimate the approximate age of a person. The case of a multiple dismemberment of three male individuals is presented, where it was essential to identify a person under 18 years of age.

Dental Forensic Kit (DFK®) and Quick Extract™ FFPE DNA extraction kit, a new workflow for obtaining dental DNA for human genetic identity.

BACKGROUND: Most of the protocols described for obtaining DNA from dental tissues are methods that involve major laboratory equipment and many hours of work. They are also methodologies that almost destroy the tooth. AIM: Our aim was to develop an innovative workflow for optimizing dental DNA extraction from teeth. Our methodological proposal is a new workflow for obtaining dental DNA for human genetic identity using Dental Forensic Kit (DFK®) and Formalin-Fixed Paraffin-Embedded (FFPE™) DNA extraction kit. METHODS: Two different dental samples groups were assayed with DFK® and FFPE™. The first group corresponded to extracted teeth from living donors and the second group was considered in real conditions with challenging teeth from corpses. Genomic Dental DNA was amplified and genotyped with platforms Identifiler Plus™, Power Plex 21™ and Global Filer ™ kits. RESULTS: Our workflow was useful in obtaining dental DNA and partial and complete genetic profiles, from teeth of both study groups. DFK® kit worked in a conservative treatment of teeth generating dental tissues (pulp and cement) and FFPE™ for DNA extraction was a very cheap, quick and easy method for obtaining genomic dental DNA. CONCLUSIONS: The innovative method and the workflow proposed herein allows obtaining robust and reliable genetic profiles, from dental tissues. DFK® kit works optimizing the treatment of dental tissues and FFPE™ demonstrates a new use in forensic genetics.

Computerized morphometry of the area of the hard palate and of palatal rugae: a cross-sectional study / Morfometría computarizada del área del paladar duro y de las arrugas palatinas: un estudio transversal

Abstract Background: The evaluation of palatal rugae in human identification is important because these structures can remain intact for up to seven days after death. Aim: To compare the area and density of the palatal rugae between ages groups and genders. Settings and Design: A cross-sectional study. Methods and Material: Dental plaster models obtained from patients at the Orthodontic Clinic of University of Uberaba were selected. Two hundred patients were divided into four groups: Group 1:10-15 years; Group 2:16-30 years; Group 3:31-50 years; and Group 4:51-70 years. The palatal rugae and hard palate of each plaster model were outlined and photographed. The evaluation of the area of the hard palate and palatal rugae was performed using the ImageJ software. Statistical analysis used: Kolmogorov-Smirnov, Kruskal-Wallis, Chi-square and Spearman correlation tests using GraphPad Prism 5 statistical software. Results and conclusión: The areas of the palatal rugae and of the hard palate were significantly smaller in the group 4. There was a significant negative correlation between age and palatal rugae area, and between age and hard palatal area. The present study was the first to demonstrate that patients between 51 and 70 years have a smaller palatal rugae area and a smaller hard palate area when compared to other groups. Thus, the evaluation of the hard palate area and of palatal rugae could be used as an adjunct with other methods to determine the age group of an individual; however studies using larger sample size are needed to validate this observation.

A Novel Computer-Assisted Method of Bite Mark Analysis for Gender Determination.

Background: Bite mark analysis is an imperative area of forensic odontology and considered the commonest form of dental evidence presented in the criminal court. The process of comparing bite marks with a suspect's dentition includes analysis and measurement of shape, size, and position of an individual's teeth. The present study was aimed to evaluate the bite marks of males and females using a novel indirect computer-assisted method and explicate its application in forensic odontology. Materials and methods: 60 subjects (30 males and 30 females) with normal occlusion were included in the present study. Bite registrations were obtained with help of modelling waxes, and positive replicas were prepared with dental stone and barium powder. Intraoral periapical radiographs were taken for the same. The radiographs obtained were scanned and analyzed by measuring tools using Sidexis Next Generation software. Intercanine distance (ICD), line AB, angle ABX, and angle ABY were measured. The Kruskal-Wallis test was performed to compare the bite marks of males and females. Results: The mean ICD of males and females was found to be 32.95 mm and 29.84 mm, respectively, and was statistically highly significant with a p value <0.001. The mean ICD, line AB, and angle ABX were found to be higher in males when compared to females. Conclusion: Analysis of bite marks using this novel computer-assisted method is a simple, reliable, easily reproducible, and economical technique with confidentiality of the identity of the participants involved.

A forensic identification case and DPid - can it be a useful tool?

OBJECTIVE: The aim of this study was to show DPid as an important tool of potential application to solve cases with dental prosthesis, such as the forensic case reported, in which a skull, denture and dental records were received for analysis. MATERIAL AND METHODS: Human identification is still challenging in various circumstances and Dental Prosthetics Identification (DPid) stores the patient's name and prosthesis information and provides access through an embedded code in dental prosthesis or an identification card. All of this information is digitally stored on servers accessible only by dentists, laboratory technicians and patients with their own level of secure access. DPid provides a complete single-source list of all dental prosthesis features (materials and components) under complete and secure documentation used for clinical follow-up and for human identification. RESULTS AND CONCLUSION: If DPid tool was present in this forensic case, it could have been solved without requirement of DNA exam, which confirmed the dental comparison of antemortem and postmortem records, and concluded the case as a positive identification.

A forensic identification case and DPid - can it be a useful tool?

Abstract Objective The aim of this study was to show DPid as an important tool of potential application to solve cases with dental prosthesis, such as the forensic case reported, in which a skull, denture and dental records were received for analysis. Material and Methods Human identification is still challenging in various circumstances and Dental Prosthetics Identification (DPid) stores the patient's name and prosthesis information and provides access through an embedded code in dental prosthesis or an identification card. All of this information is digitally stored on servers accessible only by dentists, laboratory technicians and patients with their own level of secure access. DPid provides a complete single-source list of all dental prosthesis features (materials and components) under complete and secure documentation used for clinical follow-up and for human identification. Results and Conclusion If DPid tool was present in this forensic case, it could have been solved without requirement of DNA exam, which confirmed the dental comparison of antemortem and postmortem records, and concluded the case as a positive identification.

Testing a Novel 3D Printed Radiographic Imaging Device for Use in Forensic Odontology.

There are specific challenges related to forensic dental radiology and difficulties in aligning X-ray equipment to teeth of interest. Researchers used 3D printing to create a new device, the combined holding and aiming device (CHAD), to address the positioning limitations of current dental X-ray devices. Participants (N = 24) used the CHAD, soft dental wax, and a modified external aiming device (MEAD) to determine device preference, radiographer's efficiency, and technique errors. Each participant exposed six X-rays per device for a total of 432 X-rays scored. A significant difference was found at the 0.05 level between the three devices (p = 0.0015), with the MEAD having the least amount of total errors and soft dental wax taking the least amount of time. Total errors were highest when participants used soft dental wax-both the MEAD and the CHAD performed best overall. Further research in forensic dental radiology and use of holding devices is needed.

Extra-oral dental radiography for disaster victims using a flat panel X-ray detector and a hand-held X-ray generator.

BACKGROUND: Forensic odontologists commonly incise the skin for post-mortem dental examinations when it is difficult to open the victim's mouth. However, it is prohibited by law to incise dead bodies without permission in Japan. Therefore, we attempted using extra-oral dental radiography, using a digital X-ray equipment with rechargeable batteries, to overcome this restriction. MATERIALS AND METHODS: A phantom was placed in the prone position on a table, and three plain dental radiographs were used per case: "lateral oblique radiographs" for left and right posterior teeth and a "contact radiograph" for anterior teeth were taken using a flat panel X-ray detector and a hand-held X-ray generator. The resolving power of the images was measured by a resolution test chart, and the scattered X-ray dose was measured using an ionization chamber-type survey meter. RESULTS: The resolving power of the flat panel X-ray detector was 3.0 lp/mm, which was less than that of intra-oral dental methods, but the three extra-oral plain dental radiographs provided the overall dental information from outside of the mouth, and this approach was less time-consuming. In addition, the higher dose of scattered X-rays was laterally distributed, but the dose per case was much less than that of intra-oral dental radiographs. CONCLUSION: Extra-oral plain dental radiography can be used for disaster victim identification by dental methods even when it is difficult to open the mouth. Portable and rechargeable devices, such as a flat panel X-ray detector and a hand-held X-ray generator, are convenient to bring and use anywhere, even at a disaster scene lacking electricity and water.

Accuracy of 3D scanners in tooth mark analysis.

The objective of this study was to compare the accuracy of contact and laser 3D scanners in tooth mark analysis. Ten dental casts were scanned with both 3D scanners. Seven linear measurements were made from the 3D images of dental casts and biting edges generated with DentalPrint© software (University of Granada, Granada, Spain). The uncertainty value for contact 3D scanning was 0.833 for the upper dental cast and 0.660 mm for the lower cast; similar uncertainty values were found for 3D-laser scanning. Slightly higher uncertainty values were obtained for the 3D biting edges generated. The uncertainty values for single measurements ranged from 0.1 to 0.3 mm with the exception of the intercanine distance, in which higher values were obtained. Knowledge of the error rate in the 3D scanning of dental casts and biting edges is especially relevant to be applied in practical forensic cases.

Odontología forense III: rugas palatinas y huellas labiales en identificación forense / Forensic dentistry III: palatal rugae and lip prints in forensic identification

Aunque existen métodos de identificación humana más o menos frecuentes en uso, todos ellos se soportan en la comparación inequívoca, científica y fiable, de una información conocida con la obtenida de los restos o de las huellas a procesar. Desde una perspectiva odontológica forense, los surcos labiales, las rugas palatinas y sus negativos o huellas, han sido reconocidos como patrones morfológicos que permitirían identificar a una persona en circunstancias específicas. Estos elementos han sido estudiados tanto comparativa como independientemente buscando detectar las características individuales y poblacionales que permitan reforzarlos como herramientas significativas: se ha informado que tanto la Queiloscopía (el estudio de las huellas labiales) como la Rugoscopía (el estudio de las rugas palatinas) definen rasgos únicos para cada individuo, por lo tanto utilizables razonablemente para una identificación forense. Dado que los reportes de casos forenses permiten identificar cambios en las conductas criminales, en los patrones morfológicos característicos o en la manera de presentar la evidencia pericial, se presenta una revisión de reportes de casos con utilización de evidencia rugoscópica y queiloscópica, junto con discutir sus proyecciones hacia la comunidad científica forense

Even though there exist more or less frequent methods of human identification in use, all of them are supported in the unequivocal, scientific and reliable comparison of known information with the obtained one of the remains or of the prints to processing. Between these methods, and from a dental forensic point of view, the lip prints, the palatal rugae, and their negatives or prints have been admitted as morphologic patterns, which would allow identifying a person in specific circumstances. These elements have been studied comparatively as well as independently trying to detect individual and demographical characteristics that allow to reinforce them as significant tools: it was informed that the Cheiloscopy (the study of the lip prints) as well as the Rugoscopy (the study of palatal rugae) both define unique traits for every individual; therefore, they are useful reasonably for a forensic identification.Since the forensic case reports may help to identify changes in criminal behaviours, in the morphologic typical patterns or in the way of presenting the expert evidence, a review of case reports with utilization of rugoscopical and cheiloscopical evidence is presented, and their projections toward the scientific forensic community are discussed

A simple safe, reliable and reproducible mechanism for producing experimental bite marks.

With improving technology it should be possible to develop an objective, reliable and valid method that can be undertaken by most forensic Odontologists without recourse to expensive or bulky equipment. One of the main factors that affect the physical appearance of bitemark is the amount of force applied during biting. There is little evidence relating the appearance of a bite mark to the amount of force applied and how that force relates to the biters maximal biteforce. This paper describes simple apparatus that can be used to inflict experimental bites on living subjects reproducibly and with minimal risk. The aims of this study are to report on the development of a mechanical apparatus that produces experimental bitemarks on living human subjects with a known force in a safe, reliable and reproducible manner and to relate the force applied during production of the experimental bitemark to the maximum bite force of the biter. Maximum bite force of one of the authors was determined as 324 N. Experimental bitemarks were inflicted on living subjects with known weights. Weights of up to 10 kg were well tolerated by the subjects. The relation between forces used to inflict bites and the maximum bite force of the author is reported, with 10 kg being approximately one third of the maximum bite force. The apparatus was well tolerated and the results were reliable and reproducible. The results from this study could help in determining the severity of bitemarks. This apparatus could help researchers in developing objective based bitemark analysis techniques.

Digital radiological research in forensic dental investigation: case studies.

The advent of dental digital radiology and new portable X-ray devices allows the execution of periapical X-ray images not only in the dental surgery but also in hitherto difficult locations such as field military hospitals, archaeological excavation sites, morgues and in cases of house arrest. In this work authors evaluated the feasibility of Nomad Examiner (Aribex inc.) handheld X-ray device combined with a digital sensor and a portable pc in forensic odontology applications. Employed for the first time forensically during the 2004 Tsunami victim identification process, the Nomad Examiner has now passed all security and conformity requirements of US and EU regulations. Examples of the practical use and the technical features of this device are seen when employed in odontological assessment of skeletonised and carbonized individuals and the assessment of individuals under house arrest complaining dental lesions. Results from the use this portable device demonstrate the benefits of a dental radiological assessment during an autopsy with the aim of human identification and the importance of a complete dental assessment (clinical and radiological) when evaluating dental traumatic lesions of individuals who cannot visit a dental surgery. In the first example forensic dentist would work alongside a forensic pathologist. On the other hand in the second example an odontologist - dentist could be appointed as an expert witness directly by a Court.

Usefulness of Forensic Dental Symbols© and Dental Encoder© database in forensic odontology.

A new universal graphic dental system, Forensic Dental Symbols(©), has been created to provide precision in the construction of dental records, improve standardization, and increase efficiency in dental identification procedures. Two hundred and thirty-four different graphic symbols representing the most frequent clinical status for each tooth were designed. Symbols can be then converted to a typographic font and then are ready to use in any computer. For the appropriate use, manipulation, and storage of dental information generated by the Forensic Dental Symbols(©), Dental Encoder(©) database has been created. The database contains all the information required by INTERPOL Disaster Victim Identification (DVI)-dental-forms. To explore the possibilities that Dental Encoder(©) offers, an antemortem dental database from a Spanish population of 3920 military personnel had been constructed. Data generated by Dental Encoder(©) were classified into sex and age groups. The program can perform an automatic search of the database for cases that match a selected clinical status presented in a single tooth or a combination of situations for several teeth. Moreover, Dental Encoder(©) allows information to be printed on INTERPOL DVI-dental-forms, or the inclusion of any completed form into any document, technical report, or identification of dental report.

New device for collecting intra-oral findings of unknown body.

In dental identification, the collection of intra-oral images is extremely important. We propose the Dental Watch(®) as a new device for collecting intra-oral findings in situations where sufficient jaw-opening or adequate lighting cannot be obtained in such cases of dead bodies within a day after death or burned bodies encountered in mass disaster. This device is an improved home video camera for taking intra-oral images. It is lightweight and cordless, allowing it to be operated with one hand, and an audio function allows comments to be made and recorded on obtaining findings at the same time as images are taken. In addition, this device allows images of the entire oral cavity to be taken comparatively easily, even when only a minimal degree of jaw movement is available. This device is extremely useful in situations where a single dentist inspector must obtain findings and make an accurate and detailed Dental Chart.

Bite marks: physical properties of ring adhesion to skin-phase 1.

Unsupported excised skin may shrink by as much as 50% or more. In 1981, a method was developed for ring adhesion to skin with the goal of minimizing tissue distortion upon excision. Five modified versions of the technique bearing the author's name followed (Dorion types I, II, III, IV, and V). The scientific literature reveals little supporting empirical evidence for the preferential use of one adhesive/suturing technique over another. This study compares the use of various bonding materials (Loctite Super Glue gel(®) , Dermabond™, Vetbond™), cleaning agents (ethanol, dishwashing liquid, and shaving cream), and depilatory (Veet(®) ) on the effects of ring adhesion to skin. The conclusions indicate that surface wetness is the most influential factor affecting ring adhesion to skin, followed by the type of bonding material, its "freshness," and by the cleaning agent used to prepare the skin. The use of a depilatory or shaving cream is to be avoided.

A comparison of lip prints between Aryans-Dravidians and Mongols.

CONTEXT: Lip prints are very useful in forensic investigation and personal identification. Like finger prints, even lip prints can be instrumental in identifying a person positively. AIMS: Indians are closer to Mongoloids than to Caucasoids or Negroids as indicated by the phylogenetic tree. Most of the studies on lip prints are done in their own population. We have compared lip prints of Manipuris with other Indians (Aryans and Dravidians) who are both close to Mongoloid race and are genetically similar. MATERIALS AND METHODS: A total of 100 students 50 males and 50 females were selected of whom 30 males and 30 females were of Aryan and Dravidian features and 20 males and 20 females showed the Mongol features. Study materials used were Red colored lipstick, Lip brush, Cellophane tape, White chart paper and Magnifying lens. The lip prints were analyzed by dividing them into eight compartments. RESULTS: Analysis of lip prints showed that the most common and the least common pattern in both males and females (Aryans-Dravidians and Mongols) were the same, but the compartment wise distribution of the lip patterns was different. CONCLUSION: In the present study, it is established that there is no similarity of lip prints from one individual to another individual and between males and females. Regarding the comparison with Mongols, more studies with a larger sample size is necessary.

Dental age estimation from the developmental stage of the third molars in Iranian population.

A sharp increase in forensic age estimation of living persons has been observed in recent years. However, ethnic populations residing in different countries have been insufficiently analyzed. The aim of this study was to achieve a referral database and regression equations for dental age estimation of unaccompanied minors of Iran nationality. A total of 1200 orthopantomograms were collected from original Iran and equally divided in age categories between 10 and 27 years. On the radiographs, the developmental stage of the third molars was scored applying a Demirjian et al. scoring technique. Inter- and intra-observer reliabilities were tested using kappa statistics. Correlation between the scores of all four wisdom maxillary and mandibular third molars teeth and left/right symmetry were evaluated with spearman correlation coefficient. Student's t-test on asymmetry was performed and regression formulas were calculated. The present database was the first to assemble third molar developmental scores on radiographs of Iran individuals and provided more appropriate dental age estimation of unaccompanied Iran minors. To enhance the accuracy of forensic age estimates based on third molars mineralization, the use of population-specific standards is recommended.

Image quality assessment and medical physics evaluation of different portable dental X-ray units.

INTRODUCTION: Recently developed portable dental X-ray units increase the mobility of the forensic odontologists and allow more efficient X-ray work in a disaster field, especially when used in combination with digital sensors. This type of machines might also have potential for application in remote areas, military and humanitarian missions, dental care of patients with mobility limitation, as well as imaging in operating rooms. OBJECTIVE: To evaluate radiographic image quality acquired by three portable X-ray devices in combination with four image receptors and to evaluate their medical physics parameters. MATERIALS AND METHODS: Images of five samples consisting of four teeth and one formalin-fixed mandible were acquired by one conventional wall-mounted X-ray unit, MinRay 60/70 kVp, used as a clinical standard, and three portable dental X-ray devices: AnyRay 60 kVp, Nomad 60 kVp and Rextar 70 kVp, in combination with a phosphor image plate (PSP), a CCD, or a CMOS sensor. Three observers evaluated images for standard image quality besides forensic diagnostic quality on a 4-point rating scale. Furthermore, all machines underwent tests for occupational as well as patient dosimetry. RESULTS: Statistical analysis showed good quality imaging for all system, with the combination of Nomad and PSP yielding the best score. A significant difference in image quality between the combination of the four X-ray devices and four sensors was established (p<0.05). For patient safety, the exposure rate was determined and exit dose rates for MinRay at 60 kVp, MinRay at 70 kVp, AnyRay, Nomad and Rextar were 3.4 mGy/s, 4.5 mGy/s, 13.5 mGy/s, 3.8 mGy/s and 2.6 mGy/s respectively. The kVp of the AnyRay system was the most stable, with a ripple of 3.7%. Short-term variations in the tube output of all the devices were less than 10%. AnyRay presented higher estimated effective dose than other machines. Occupational dosimetry showed doses at the operator's hand being lowest with protective shielding (Nomad: 0.1 microGy). It was also low while using remote control (distance>1m: Rextar <0.2 microGy, MinRay <0.1 microGy). CONCLUSIONS: The present study demonstrated the feasibility of three portable X-ray systems to be used for specific indications, based on acceptable image quality and sufficient accuracy of the machines and following the standard guidelines for radiation hygiene.

3D imaging in forensic odontology.

This paper describes the investigation of a new 3D capture method for acquiring and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded into a 2D space. Although strict guidelines (BAFO) exist, these are time-consuming to follow and, due to their complexity, may produce errors. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. Proposed Solution: a series of experiments are described in this paper to demonstrate that the potential of a 3D system might produce suitable results. The experiments tested precision and accuracy of the traditional 2D and 3D methods. A 3D image capture device minimises the amount of angular distortion, therefore such a system has the potential to create more robust forensic evidence for use in courts. A first set of experiments tested and demonstrated which method of forensic analysis creates the least amount of intra-operator error. A second set tested and demonstrated which method of image capture creates the least amount of inter-operator error and visual distortion. In a third set the effects of angular distortion on 2D and 3D methods of image capture were evaluated.