Textbook of Forensic Odontology KMK Masthan
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Introduction to Forensic ScienceCHAPTER 1

  • The word forensic is derived from the Latin word, forensic meaning public. The word science can be defined as systematized knowledge through study using the scientific method. The scientific method is the principles and procedures for the systematic pursuit of knowledge involving the recognition and formulation of a problem, the collection of data through observation and experimentation, and the formulation and testing of hypotheses. Forensic science refers to areas of endeavour that can be used in a judical setting and accepted by the court and the general scientific community to separate truth from untruth.
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    Fig. 1.1:
  • Forensic odontology can be defined as a branch of dentistry which deals with the proper handling and examination of dental evidence and with the proper evaluation and presentation of dental findings in the interest of dentist.
  • Some authors prefer to use the term forensic odontostomatology as its purview includes the whole of orofacial region. The term forensic dentistry is also used interchangeably with forensic odontology.
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    Figs 1.2A and B:
  • Some of the major landmarks in the evolution of forensic dentistry are elaborated here.
  • The dentition was, thought to be, used for the first time in 49 AD, in identification of an individual by Agrippina, the wife of Claudius-Roman emperor. She used the peculiar features present in the teeth of her rival and divorcee of her husband, Lollia Poulina, for identification of the body after getting her beheaded.
  • Around third century BC the great Indian sage Vatsayana depicted, in detail, the human bitemarks and its classification of skin pertaining to love making for the first time in Indian literature.
  • In India, the Rathore raja of Kannauj, Jai Chandra was recognized by his false teeth after he was beaten and killed in the battle. This was, in 1199 AD, probably the first case of identification from dention reported in India. This is given in Elphinstone's “History of India” 5th edition.
  • John Talbot, Earl of Shrewsbury, a veteran warrior in his 80's who fell in the battle of Castillion was identified by his teeth in 1453. Dentition also helped to identify the body of Charles the Bold, in 1477, who was found without armor and clothes. The earliest case of bitemark analysis was the Salem trial of 1692, culminated in the conviction of Rev George Boroughs.
  • In 1770's Paul Revere, a practicing dentist in US, identified the remains of his friend Dr Joseph Warren from the silver wire fixed bridge made by him. This is thought to be the first case of identification of a person by a dentist. The family dentist made a definite identification of John Wilkes Booth's body from dentition to bury the controversies surrounding his death.
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    Fig. 1.3:
  • Dr Oscar Amoedo, Professor at a Dental School in Paris, presented a paper entitled “The role of the dentists in the identification of the victims of the catastrophe of the Bazaar de la Charite, Paris, 4 May 1897” at the International Medical Congress of Moscow, he included many of the concepts of dental identification used in the above disaster in his blood “L' Art Dentaire enmedicine Lagale” published in 1898. It was he who suggested the need for an Internationals System of Uniform Charting and a Mutual Understanding of Nomenclature. He is considered as father of forensic odontology.
  • Advertisements, especially in professional journals, were found to be helpful in assisting the coroner in identifying the victim. It was first used in 1939 by Commissioner Edward J Hickey, who advertised in Journal of American Dental Association. It was seen by a Massachusetts dentist who recognized the bridge constructed by him leading to the identification of the victim and charting the events leading to his death. Later such advertisements appeared in several dental journals like British Dental Journal.
  • Dentition was an important lead in the identification of the remains of various leaders who were killed like Zia Ul Haq, former Pakistani president and Rajiv Gandhi, Former Indian Prime Minister. In 1966 Gustafson wrote a comprehensive textbook “Forensic Odontology” which was considered as the Bible in its time. The first format instruction program in forensic dentistry was started at the Armed Forces Institute of Pathology in US in the sixties.
  • Although teeth had been used in the identification of individuals throughout history, mostly as isolated cases, it was never an organized field as it is now. It is perhaps more significant in the present day world. Nowadays a lot of people are found to be missing, dead, murdered or killed in accidents. The identification of these corpses, many a times mutilated bodies, is of paramount importance from a social, emotional and legal view points. Forensic odontology also monitors its own parent profession against malpractice.
  • The American Academy of Forensic Sciences, the largest forensic group in the world with a membership of more than 5300 forensic scientists, recognizes 10 areas of forensic endeavor: Criminalistics, engineering science, general, jurisprudence, odontology, pathology/biology, psychiatry and behavior science, questioned documents, toxicology, and physical 3anthropology. The pathologist is helpful in determining the time of death by looking at factors such as rigor mortis, livor mortis, postmortem body temperature, decomposition, and chemical changes occuring after death. An autopsy consists of several parts, charting all the external injuries, anatomic dissection, histologic studies, toxicology, and cultures.
  • Criminalistics is the branch of forensic science involved in the area of laboratory testing of various types of physical evidence, including biologic fluids, DNA, and suspicious chemicals. Criminalists can determine the qualitative and quantitative values of unknown chemicals.
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  • The field of engineering science generally is involved with the structural aspects of a crime scene or accident scene.
  • Jurisprudence is the area of forensic science dealing with the judicial process and the weight placed on various types of forensic information in adjudicating a legal issue.
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  • Psychiatry and behavior science is an area of forensic science that studies the behavioral pattern of criminals and often helps the court determine whether a suspect is able mentally to stand trial.
  • Questioned documents is the area of forensic working with the verification that a written document is what it is purported to be and the signature on the document is authentic.
  • Toxicology is the field of study involving the testing of drug levels in biologic fluids and their reactions in the human body.
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    Fig. 1.6:
  • The general section of forensic science includes members that do not fit into the other recognized areas but are involved in the forensic sciences.
  • The physical anthropology of forensic science deals with the reconstruction of an individual from the bones or skeleton. With their ability to determine the location of grave or burial sites, anthropologists are particularly helpful when a body is buried.
  • The pathology/biology section deals with the pathologic and physiologic changes of a body before and after death.
  • The autopsy is a crucial part of many death investigations, helping to determine the cause and manner of death. The cause of death is any injury, disease, metabolic condition, or malformation that plays a part in an individual's death. The manner of death is the situation in which the death occurs and usually is limited to natural, accident, homicide, suicide, or undetermined.
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    Fig. 1.7:
  • American Society of Forensic Odontology.
  • Australian Society of Forensic Odontology
  • British Association for Forensic Odontology
  • Gemeinsamer Arbeitskreiss fur Forensische Odonto Stomatologie (Germany).
  • Indian Association of Forensic Odontology
  • New Zealand Society of Forensic Dentistry.
  • Swedish Society of Forensic Odontology.
  • The Medicolegal Society of Singapore.
  • American Board of Forensic Odontology.
  • Bangladesh Society of Forensic Odontology.
  • The Croatian Group of Forensic Odontologists.
  • The Hong Kong Group of Forensic Odontologists.
  • The Indonesian Group of Forensic Odontologists.
  • The Israeli Group of Forensic Odontologists.
  • The Lithuanian Group of Forensic Odontologists.
  • The Singapore Group of Forensic Odontologists.
  • The Swiss Society for Forensic Medicine Odontological Section.
  • The Ukraine Association of Forensic Medical Experts.
  • Forensic odontology is the practice related to law. It can be considered as an area of specialization under dentistry as well as forensic medicine because knowledge of both the fields are vital for its activities. Although this branch appears new to us, it is probably as old as man kind itself as inscribed in the Bible. The Bible says Adam was convinced by Eve to put a ‘bitemark' in an apple. But the renewed interest in this subject began in the sixties. It is an established specialty in some of the countries but in India it is still in the seminal stages.
  • The various materials used in identification of human remains are the personal belongings like pieces of clothing, jewellery, fingerprints from blood grouping and dentition. Human dentition is considered as hard tissue analogue to the fingerprints. It is almost as unique to an individual as fingerprints. Each adult human dentition consists of thirty-two teeth of which some may be missing or malformed. Effects of various environmental events, like nutrition, drugs, etc. may also be manifested on the teeth. Each race has characteristic appearances on the dentition. Then a wide variety of manipulations being done on the dentition such as restorations also add to its distinctive pattern. With such an extensive array of differences, it is extremely rare to have two similar dentitions. Apart from this, teeth are one of the most durable part of our body, which can withstand more assaults than any other part of the body. This is particularly useful in the identification of bodies in mass disasters and natural calamities. Teeth are also frequently seen in fossils.
  • Forensic odontologist should have a through knowledge about the dentistry, especially the basics of anatomy including dental anatomy. He also should have an extensive knowledge of various branches of dentistry, which helps in better handling of the situations. An awareness of forensic pathology and the methods of autopsy is merited. Furthermore a comprehensive cognizance of the pertaining laws to the legal implications involved in it. So, a forensic odontologist is much more than dentist.
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    Figs 1.8A to C:
Forensic odontology includes two distinct areas, identification and bitemarks.
  • Identification of an individual, living or dead, is based on the theory that all individuals are unique. All humans are born with anomalies or acquired artifacts. An anomaly is a unique congenital condition (e.g. mesiodens, missing lateral incisor, hemangiomas, spinal bifida). An artifact is a man-made alteration (e.g. a dental restoration, extracted tooth, scar, tattoo, appendectomy).
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    Fig. 1.9:
  • When an unidentified body is found, it is assumed that it could be anybody. By classifying the individual into characteristic groups (e.g. age, sex, race, height), the possibilities are narrowed. When any anomaly or artifact is found, it makes the group smaller. The more unique the characteristic, the smaller the group becomes. As more unique characteristics are noted, the comparison group becomes smaller until it reaches unity. At that point, identification can be made. An antemortem record showing these unique features must be found to match with the postmortem features of the victim.
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  • There are two basic types of identification, the unknown and confirmation. An unknown victim is one that has no identification on the body, and it could be almost anyone. A confirmation type of identification in one in which there is a high probability that victim may be a particular person. Forensic odontology usually is the best method to identify burned or decomposed bodies. Records of mass disasters indicate that dental identification is the most successful means of identification.
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    Fig. 1.11:
  • Other distinct area of forensic odontology is bitemark identification. A pattern injury is any injury in which the instrument of injury can be determined and possibly be individualized as the weapon making the injury. A bitemark is an injury to skin in which the instruments of injury are teeth. The injury is a contusion caused by the rupture of small blood vessels as the individual teeth compress the tissue. Bitemarks leave blurred contusions, arrangement of the teeth is unique in every individual, and no two dentitions are identical.
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    Fig. 1.12:
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    Fig. 1.13:
    If the teeth leave definite marks, it should be possible to individualize them to a particular individual. Contusions tend to leak into the surrounding tissue, however, making the mark blurred or fuzzy. Despite this blurring, the forensic examiner often can narrow down the number of potential biters by excluding those who could not have made the bitemark because of definite differences (e.g. arch size, arch contour, missing teeth). By eliminating the suspects who could not have made the mark, the group of potential biters becomes small sometimes only one individual. If the suspect's bite is consistent with the bitemark, he or she may be the biter.