Bite Mark Analysis- A Crucial Forensic Evidence

Background: Bite mark analysis has a critical role in forensic cases. Bite marks have been recorded has played an important role in the criminal justice system. Aims: Based on the fact that no two mouths are alike, this review article draws a perfect association between dentistry and law. The present review describes the history of bite mark analysis along with its classification, characteristics, mechanism of production, collection of evidence from both the suspect and the victim, comparison techniques and technical aids. Materials and Methods: Data was collected and analyzed from the literature already published in books and electronic data- base searches of PubMed and Google Scholar. Results: Forensic odontologists should be familiar with all methods of bitemark comparisons and appropriately use those methods that are indicated for the case at hand. Conclusion: Bite mark being a valuable alternative to fingerprinting and DNA identification, the analysis of bite mark evidence does have place in the courtroom aiding the legal system in answering crucial questions about potential suspects and victims.

Application Status and Prospect of Bite Mark Evidence in Forensic Odontology / 法医学杂志

Bite marks are increasingly common in violent cases such as child abuse and sex crimes. Bite marks are often the result of a suspect's attack or a victim's self-defense. Because human teeth vary in size, shape and arrangement, bite marks on objects such as skin and food are characteristic. By using this principle, forensic odontology can identify or exclude suspects by comparing actual bite marks with the teeth marks in the mouth. In this paper, the practical application of bite mark evidence, the research status and problems of bite mark analysis are briefly reviewed, and the prospect of bite mark analysis is also discussed.

Exploring bite marks on different types of skin tones / Explorando as marcas de mordida em diferentes tipos de tons de pele

The analysis of bite marks is a challenging and convoluted part of Forensic Odontology. Various interrelated factors such as location of the bite and skin elasticity complicate the bite mark analysis. The relationship between the bite mark and the biochemical properties of skin has been well-documented but there is need to consider the variety of skin tones as a factor to explore. The aim of this pilot study was to analyse the appearance of bite marks on 5 different types of skin tones of 15 subjects (6 males and 9 females) from 11 nationalities and age ranged from 21 to 46 years. A pair of 3D printed dental cast was transferred onto a mechanical apparatus for production of experimental bitemarks by using 12.5 kg of weight. Common imaging modalities including conventional, infrared and ultraviolet light were used to record the bite mark images for following visual assessment. The different skin tones were categorized using Fitzpatrick scale (1975) and a colour chart was used to compare the changes on skin after 15 minutes of bite registration. According to the results, the force was well tolerated by the subjects producing a well-defined bite mark, although males showed a less prominent mark than females irrespective of the skin tone and nationality. Neither bruises nor significant changes in the colour of bite mark could be appreciated among the subjects. The different types of skin tones did not affect the registration of bite mark applying a force of 122.5.N for 15 seconds in this sample

A análise das marcas de mordida é a parte mais desafiadora e complicada da Odontologia Forense. Vários fatores inter-relacionados, como a localização da mordida e a elasticidade da pele, complicam a análise da marca de mordida. A relação entre a marca de mordida e as propriedades bioquímicas da pele tem sido bem documentada, mas é preciso considerar a variedade de tons de pele como um fator a ser explorado. O objetivo deste estudo piloto foi analisar o aparecimento de marcas de mordida em 5 tipos diferentes de tons de pele de 15 indivíduos (6 homens e 9 mulheres) de 11 nacionalidades e idades entre 21 a 46 anos. Um par de modelos dentários impressos em 3D foi transferido para um aparelho mecânico para a produção de marcas de mordida experimentais usando 12,5 kg de peso. Modalidades de imagem digital como convencional, infravermelha e ultravioleta foram usadas para registrar as imagens da marca de mordida para posterior avaliação visual. Os diferentes tons de pele foram categorizados usando a escala de Fitzpatrick e uma cartela de cores foi usada para comparar as alterações na pele após 15 minutos de registro da mordida. De acordo com os resultados a força foi bem tolerada pelos sujeitos, produzindo uma marca de mordida bem definida, embora os homens mostraram uma marca menos proeminente do que as mulheres, independentemente do tom da pele e da nacionalidade. Nenhum hematoma ou mudanças significativas nas cores das marcas de mordida foram encontrados entre os indivíduos. Os diferentes tipos de tons de pele não afetaram o registro da marca de mordida aplicando uma força de 122,5 N por 15 segundos nesta amostra.

Correlation between bizygomatic and maxillary central incisor width for gender identification / Correlação entre a distância bizigomática e a espessura de incisivo central maxilar para identificação de gênero

Objective: The aim of the present study is to analyze and evaluate the applicability of bizygomatic and maxillary central incisor width in identifying the sex of an individual for anthropological studies. Material and Methods: The study was conducted on 100 individuals in a private dental institution. The width of the central incisor was measured by requesting the subject to bite onto a sheet of modelling wax. The bizygomatic width was calculated with the help of a divider by taking the most prominent area of the zygomatic arch as the reference point bilaterally. Berry's formula was used to calculate the width of the maxillary central incisor from the bizygomatic width. Berry's Formula "Width of the maxillary central incisor = Bizygomatic width / 16." The data obtained was tabulated and analyzed statistically. Results: The results in our study indicated that the widths of both maxillary central incisors and the bizygomatic width were found to be higher in males when compared to females with a positive strong correlation. Conclusion: The Berry's index can be used for identifying the gender and can also be used for facial reconstruction. (AU)

Objetivo: O objetivo do presente estudo é analisar e avaliar a aplicabilidade da distância bizigomática e espessura de incisivos centrais maxilares na identificação do sexo de um indivíduo para estudos antropológicos. Material e métodos: O estudo foi conduzido com 100 indivíduos de uma instituição odontológica privada. A espessura do incisivo central foi medida pedindo ao sujeito que mordesse em uma folha de cera. A espessura bizigomática foi calculada com o auxílio de uma régua pegando a área mais proeminente do arco zigomático como ponto de referência bilateralmente. A fórmula de Berry foi usada para calcular a espessura do incisivo central maxilar da espessura zigomática. Fórmula de Berry: "Espessura do incisivo central maxial = Espessura bizigomática / 16". Os dados obtidos foram tabulados e analisados estatisticamente. Resultados: Os resultados em nosso estudo indicaram que as espessuras de ambos os incisivos centrais maxilares como as espessuras bizigomáticas foram maiores no sexo masculino do que no sexo feminino, com uma correlação positiva forte. Conclusão: O índice de Berry pode ser usado para identificação de gênero e também pode ser usado para reconstrução facial. (AU)

A Preliminary Study of Malay and Chinese Bite Mark in UKM Using Dental Wax / Jurnal Sains Kesihatan Malaysia

Identifi cation of unknown suspect through bite marks has always been challenging. Narrowing list of suspects through sex and race markers is always recommend but rarely utilized due to limited publication in this area. Thus, this preliminary research was aimed to study the difference of bite mark made on dental wax between sex and race. A sample size of 40 UKM undergraduates comprising of Malay (male = 10, female = 10) and Chinese (male = 10, female = 10) were used in this study. Bite mark of subject was obtained through dental wax, digitally scanned and analyzed using Image-J software. Parameters measured were anterior teeth size, intercanine width and anterior teeth relative rotation. Result indicated that mandible left canine tooth size had signifi cant sexual dimorphism (p < 0.05) in differentiating sex. The means for male and female measured were 4.63 ± 1.05 mm and 5.35 ± 0.87 mm respectively. In addition to the result, tooth size of maxillary left canine and mandible left lateral incisor were signifi cantly different (p < 0.05) between races. Means for mandible left canine Malay and Chinese were 5.27 ± 1.01 mm and 4.50 ± 1.22 mm respectively. Furthermore, left lateral incisor mandible had means of 5.15 ± 0.87 mm and 4.60 ± 0.74 mm for Malay and Chinese respectively. Unfortunately, there were no signifi cant differences for intercanine width and anterior teeth relative rotation between the two major races in Malaysia. In conclusion, this research has demonstrated the possibility of using tooth size of mandible left canine, maxillary left canine and mandible left lateral discriminate sex and race.

Odontología forense I: las huellas de mordedura / Forensic dentistry I: bite marks

Entre las pericias de identificación odontológica forense, los análisis de huellas de mordedura han representado un tópico actual, relevante y controvertido pues la unicidad de la dentición, la confiabilidad de la piel como soporte y sus técnicas de análisis, han visto un fuerte cuestionamiento a partir de una relevante casuística de condenas injustas. Mientras la literatura especializada y más actual ofrece una permanente revisión sobre protocolos y normas para la cualificación de pericias y peritos, la literatura de habla hispana no sostiene un ritmo similar, con una escasa o nula actualización de contenidos adecuados en procedimientos, investigación o reportes de casos. Dado que estos análisis ha sufrido cambios absolutos de base, y que una conveniente actualización al habla hispana permitiría la adaptación, modificación o reemplazo de sus postulados axiológicos, se presenta una revisión cronológica sobre casos y tópicos de inferencia en el análisis de huellas de mordeduras como evidencia jurídica, y se proponen y discuten nuevos postulados epistemológicos para el abordaje forense de este tipo de evidencias.

Among the forensic dental identification, the analyses of bite marks have represented a current, relevant and controversial topic. The uniqueness of the dentition, the accuracy of bite marks on skin and the analytical techniques have been severely questioned because of the relevant casuistry of wrongful convictions. While the specialized and more current literature offers a permanent review on protocols and standards for verifying expertise, the Spanish literature does not keep pace with this situation, with scanty updating of procedures, primary investigation or case reports. Since these analyses have been modified in their bases, a proper update of Spanish literature to allow the adjustment of their axioms is needed. We present a chronological review of cases and inferential issues in bite mark analysis as judicial evidence, and the new epistemological postulates for the forensic significance of this type of evidence are discussed.

Analysis of bite mark evidence.

Bite mark analysis casework strives to connect a biter to the teeth pattern present on an object linked in some way to a crime or event. The general public and some law enforcement may consider any “bite mark” case they develop to be a certainty in the quest to identify the biter. The ability of skin to register sufficient detail of a biter’s teeth is highly variable. Bite mark casework indicates that many bite marks are not well defined in detail and posses distortion due to the physical nature of skin itself. The current opinion is that bite mark can be useful in including or excluding possible suspects and ability to identify only one person as the biter. In mortal combat situations, such as the violence associated with life and death struggles between assailants and victims, the teeth are often used as a weapon. It is well known that assailants in sexual attacks, including sexual homicide, rape and child sexual abuse, often bite their victims as an expression of dominance, rage and animalistic behaviour. The teeth are a significant component of our natural arsenal.

Comparison between five commonly used two-dimensional methods of human bite mark overlay production from the dental study casts.

Aim: The present study was conducted to determine the most accurate bite mark overlay fabrication technique by studying two physical characteristics, i.e., area and rotation of biting edges of anterior teeth of thirty volunteers. The objective of the study was to evaluate the reliability and efficacy of five commonly used methods of human bite mark overlays using two dimensional (2D) digital images of dental study casts as a gold standard, to rank different methods according to statistically based determination of relative accuracy of each method and to determine its feasibility in Forensic science. Materials and Methods: Overlays were produced from the biting surfaces of six upper and six lower anterior teeth of 30 volunteers using the following five methods: a) hand tracing from study casts, b) hand tracing from wax impressions, c) xerographic method, d) radiopaque impression method and e) 2D computer-based method. Area of the biting edges of the anterior teeth and relative rotation of each anterior tooth were measured and compared. Results: The xerographic method was determined to be the more accurate method with respect to tooth area and rotation. Hand tracing methods, from either wax impressions of teeth or directly from study casts, were determined to be inaccurate and subjective. Conclusions: It is recommended that forensic odontologists discontinue the use of hand tracing overlays in bite mark comparison cases as there is lot of scope for manipulation and observer bias.

Dental Identification of Terrorist Bombing of Korean Airline: A Case Report / 대한법의학회지

A Korean Airliner, KAL 858 was exploded over Thailand on November 29, 1987. The suspect with the forged Japanese passport was dead by biting an ample of cyanide gas contained in the filter tip of a cigarette. Forensic odontological examinations including bite mark, dental age estimation and dental characteristics were performed. From these examinations, it could be assumed that (1) he had specific difference in dental treatment which suggested a North Korean by comparison of the fisherman arrested under the North Korea, (2) the filter of cigarette was positioned between the suspect's dentition, (3) he was approximately 70 years old by dental age estimation at time of death. This paper indicates that forensic odontological examination can support personal identification and the circumstances of death in international case where disguised identity plays a part.

Comparing and checking for personal identification by using bite mark / 中国法医学杂志

Objective To establish a database for models of teeth, which could provide a new technology for personal identification based upon teeth and bite mark for forensic medical practice. Method The (X, Y) digital coordinates were established based up on materials concerning shape and arrangement of the teeth by analyzing samples of 400 models of teeth. The position of every tooth's key point corresponding to the origin was obtained, thus, the characters of tooth and dental arch could be calculated rapidly according to Borland C ++ 5.0 computer language under DOS system. Results The models of teeth could be identified automatically. Among the correlative precision indexes, the length was 1.3mm, the angle was 3?. It seems reasonable to select 12-14 teeth points for studying, which needed about 5-7 complete tooth marks. Conclusion This method is one of the bases in studying personal identification relating to tooth and bite mark.