Presentation on theme: "PROF. AZZA A. HANNO (Head of Pedodontic & Community Dentistry Dept, PUA)"— Presentation transcript:
PROF. AZZA A. HANNO (Head of Pedodontic & Community Dentistry Dept, PUA)
Course Description Forensic dentistry has been a part of our esteemed profession since the Revolutionary War times. Over those many decades, the evolution of current forensic dentistry has progressed continuously to its current practice. This course will review how forensic dentistry is used in cases involving violent crime,the infliction of human bitemarks, the process of dental identification of human remains, including multiple fatality incidents, human abuse as seen in the practice of dentistry, the use of dental age estimation in modern society and the interaction of the dental record with the law in cases of malpractice and personal injury.
Course Description The course is also planned to provide the future dental professionals with elementary knowledge to play their key role by keeping comprehensible, accurate, and current quality records for each patient. In addition, the course help the future dental professionals to recognize the importance of performing a comprehensive extraoral and intraoral examination including documentation of abnormalities even bruising or bite marks. This information will be significant to an investigation of crime or abuse, or identification of human remains when a mass disaster occurs.
Course Objectives At the conclusion of this presentation, each participant should be familiar with: The main components of forensic odontology Forensic Dentistry mile stones The organizations dedicated to the field of forensic odontology The detection of criminal cases that involve the infliction of human bitemarks The factors that may affect the accuracy of bite mark identification Bite mark limitations
At the conclusion of this presentation, each participant should be familiar with: The methods of bite mark analysis The Guidelines of the American Board of Forensic Odontology (ABFO) for bite mark analyses The importance of DNA analysis The signs of child and elderly abuse The role of the dental assistant in forensic dentistry.
At the conclusion of this presentation, each participant should be familiar with: How dentistry is able to assist in dental identification of human remains, in both isolated single cases and in multiple fatality incidents Reporting of incidents of human abuse seen in the dental office How dental age estimation is used to help determine the age of criminals (adult versus child) The use of the dental record in dental malpractice and dental facial injury cases
Forensic Dentistry Forensic dentistry is one of the most rewarding and exciting subspecialties of dentistry Situations a forensic dentist might encounter range from civil issues such as identification of deceased individuals who, by virtue of circumstances of death or advanced decomposition, cannot be visually identified, to identification of mass-disaster victims, to criminal cases that involve dental evidence, such as bite marks and oral injuries.
Forensic Dentistry History-1 Dr. Oscar Amoëdo returned to Cuba in 1889 after studying at New York Dental College. He was then sent as a delegate to the International Dental Congress in Paris in 1890. He decided to stay in Paris and became a dental instructor and teacher, eventually becoming a full professor. A tragic fire at a charity event stimulated his interest in dental identification and the field of forensic odontology.
Forensic Dentistry History-1 While he was not involved with the identification of the victims from the fire, he knew many of the victims who survived and interviewed them. His accounts of the fire were presented in a paper at the International Medical Congress of Moscow and were published in English in 1897. Dr. Amoëdo wrote a thesis entitled “L’Art Dentaire en Medicine Legale”, which earned him a doctorate and served as the basis of his first comprehensive text on forensic odontology and he is considered by many to be the “Father of Forensic Odontology”
Forensic Dentistry History-2 The first forensic dentist in the United States was Paul Revere who was known for the identification of fallen revolutionary soldiers. Dr. Joseph Warren, who suffered a severe head trauma during the war, was identified by a small denture that Paul Revere had fabricated for him. Through this identification, it was made possible for Dr. Warren to be buried with full military honors.
Forensic Dentistry History-3 Dr. George Parkman was a respected professor at Harvard University who also dealt and lending money. John Webster, a colleague of his at Harvard, who was a chemist, owed Dr. Parkman a considerable amount of money. One evening, Dr. Parkman failed to return home from dinner on November 23, 1849. John Webster’s laboratory was searched. In the furnace, fragments of the maxillary jaw were discovered. At the trial, Dr. Parkman’s dentist, identified the teeth as part of the maxillary and mandibular dentures he made three years earlier for the victim. This was the first time dental evidence was used to convict a murderer.
Forensic Dentistry History-4 After the shooting of President Lincoln on April 14, 1865, John Wilkes Booth escaped and hid in a barn on a farm in Virginia. The United States Calvary found him there on April 26, 1865 and burned the barn. John Wilkes Booth left the barn and was shot and killed. However there was rumor that he had escaped. Therefore in 1893, the body was removed from a grave and examined to verify his identity. The family could not perform a visual identification, but the family dentist was able to recognize his work as well as a peculiar formation of the jaw he had noted in his records during a dental visit for the placement of a filling.
Forensic Dentistry History-5 After the end of World War II, there were rumors Adolf Hitler had escaped with his wife Eva Braun. Actually they had died together in 1945; however their bodies had been burned and then buried by Russian soldiers. Due to lack of ante-mortem and post-mortem records, it was a challenge to dispel the rumors they were still alive. Finally pieces of Hitler’s mandible were found that revealed remnants of a bridge as well as unusual forms of reconstruction to the mandible with evidence of periodontal disease. Adolf Hitler’s identity was confirmed when the work matched the records kept by his dentist, Hugo Blaschke.
Forensic Dentistry History-6 Several years after the assassination of John F. Kennedy, an English author named Michael Eddowes began raising suspicion concerning the identification of Lee Harvey Oswald. He believed the body buried in 1963 in Oswald’s grave was a Russian spy. Therefore, to set the record straight, the body was digged up and positive identification of Oswald was made on October 4, 1981 with military ante-mortem dental records.
Forensic Dentistry Areas The areas of specialty of forensic dentistry include : identification of found human remains identification in mass fatalities. Age determination of death Species,sex, and race determination Serological identification Facial reconstruction assessment of bite mark injuries assessment of cases of abuse (child, domestic partner, or family) DNA identification
Organizations Four organizations are dedicated to the field of forensic odontology, in the USA. These organizations include: the Bureau of Legal Dentistry (BOLD), the American Board of Forensic Odontology (ABFO),American Society of Forensic Odontology (ABFO) International Organization for Forensic Odonto- Stomatology (IOFOS). Other countries have their own forensic Odontological societies, including: British Association for Forensic Odontology (BAFO) Australian Society of Forensic Odontology (AuSFO). The University of British Columbia program is the only one in North America that provides graduate training in forensic odontology.
The age of a human specimen can be narrowed by evaluating the patterns of tooth eruption and tooth wear (i.e., children, adolescents, adults). Recent studies provide evidence that cementum exhibits annual patterns of deposition.
Age determination 1.Mineralization, attrition, and eruption sequence 2.Microscopic examination 3.Aspartic acid type
Age determination 1- Mineralization and eruption sequence: The human dentition follows a predictable developmental sequence starting from the 4 th month after conception till completion of permanent teeth development. Teeth erupt in a chronological sequence (racial and sex variations)
Age determination 1- Mineralization and eruption sequence: Jaw radiographs indicating tooth developmental stage and mineralization extent help determining age at death within few months in infants and within few years in teenaged individuals. Age determination from 20 years to old age becomes more difficult (slight microscopic changes within the hard tissue of teeth can help in age determination )
Age determination 2-Microscopic examination : The human dentition shows slight changes within the hard tissues of teeth : The dentinal tubules within the root apex become progressively mineralized as age progresses. This mineralization alters the refractive index of dentin, rendering it transparent when examined microscopically.
Age determination 2-Microscopic examination : The extent of root translucency may be determined by computer mapping of serial hard tissue sections. Regression tables have been used to determine age of an unidentified body within about 7 years of the correct age at death.
Age determination 3- Aspartic acid type : Amino acids are built into the tooth collagen as S- aspartic acid enantiomers. Enantiomers are pairs of molecules that are mirror images of each other in structure but cannot be superimposed By time, the S-aspartic acid enantiomers slowly undergoes racemization producing the opposite R-aspartic acid enantiomers.
Age determination 3- Aspartic acid type: Racemization : the converting of a pure enantiomers into a mixture of more than one enantiomer. 2 Mirror image converts right hand into left (racemization) The rate of racemization can be used to determine the age of the deceased person, by measuring the ratio of right-handed to left- handed enantiomeric residues in the tooth.
Species determination: Tooth anatomy: When fragments of tooth are found at the scene of a crime, comparative dental anatomy is used to determine the species using the shape of the fragment.
Species determination: The enamel rods: If this is not possible from the shape of the fragment, the enamel may be examined with light or electron microscopy, as the enamel rods differ between primate and nonprimate tissues.
Species determination: Dentinal fluids More recently, it has been shown that dentinal fluids contain specific species information, which can be used to compare to species-specific antiserum.
Sex determination: The use of dental anatomy, which is based on tooth size and shape differences between males and females. Male teeth are more angular while female teeth are more rounded.
Sex determination: Remnants of cells from fragments of tooth found at the scene of a crime can examined for the presence of Baar bodies or the sex chromosome status of the cell. A Barr body in human fibroblasts
Sex determination: Radioimmunoassay (RIA) can be used for sex hormone level determination (the ratio of testosterone to 17 B-estradiol).
Racial determination: Racial separation into the main Caucasoid, Negroid, and Mongoloid racial groups may be possible using cranial and facial morphology.
Facial reconstruction The skull and facial bones are used as a foundation to reconstruct the facial soft tissues using traditional sculpture methods.
Facial reconstruction Reconstruction of the facial soft tissue uses standard anthropologic points and measurements around the face. These points can then be connected with sculpting clay
Facial reconstruction The width of the mouth is related to the interpupillary distance. The length and shape of the nose are determined by the relationship between the inferior and superior nasal spine
Facial reconstruction Three-dimensional computer images and computed tomographic images (CT) and radiographs can be used in the replication of faces of unidentified bodies. The remains of a 5000-year person were removed from glacial ice on the Austrian- Italian border and the face of this person was reconstructed.