forensic dentistry a seminar on: guided by : dr. mehmood muthedath dr. azeela ahmed dr. aswathi m.p...
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FORENSIC DENTISTRYA SEMINAR ON:
GUIDED BY : Dr. Mehmood Muthedath Dr. Azeela Ahmed Dr. Aswathi M.P
Submitted by, Ajmal M. Angel Mery Cherian
INDEX
Introduction Background Organizations Why dental evidence? Identification Bite mark analysis Management of dental records and testimony preparation. Multiple applications Conclusions
INTRODUCTION
is the application of a broad spectrum of sciences to answer questions of interest to alegal system. Forensic dentistry is one of the branches of forensic sciences.
Some other of the branches of forensic science include;
o Forensic anthropologyo Forensic archeologyo Forensic Entomologyo Forensic Pathologyo Forensic Botanyo Forensic Chemistry
oForensic OsteologyoCriminalisticsoDigital forensicsoForensic DactyloscopyoForensic DNAanalysisoForensic linguisticsoForensic psychologyoForensic toxicologyoForensic serology
INTRODUCTION
The word forensic derived from Latin word Meaning ‘forum’ . The forum was a place in ancient Rome, were trials and debates took place and consequently served as a Court of law.Dentistry is the study of teeth.
Crime investigations
It includes : Investigation of bite marks Child abuse Lip prints
oForensic OsteologyoCriminalisticsoDigital forensicsoForensic DactyloscopyoForensic DNAanalysisoForensic linguisticsoForensic psychologyoForensic toxicologyoForensic serology
BITE MARKS
Defined by Macdonald as a mark caused by the teeth either alone or in combination with other mouth parts
It may be caused by humans or animals. They may be on tissue, food items or objects
Usually associated with sex crimes, violent fights and child abuse
Hence matching the bite marks of a suspect dentition enable the investigatory officers to implicate the suspect in a crime
BITE MARKS
CLASSIFICATION OF BITE MARKS
Cameron & Sam's classification a relatively simple, wide encompassing classification. This is based on the type of agent producing the bite mark & the material exhibiting it.
AGENTS:- Human Animal
Does the age of the bite mark correspond to the time & type of crime??????
Are there any unique individual characteristics in the bite marks ??????
Can these characteristics be compared to the teeth of suspect????????
Bite mark analysis and comparison
The dynamics of bating mark analysis and its comparison to the suspect teeth is challenging. in addition to jaw movements, one needs to consider movement on part of the victims, the flexibility of the bitten tissue, swell as possible distortion introduced during photography
It is important to recognize uncommon characteristics of the bite mark such as presence or absence of a particular tooth, its dimensions,rotations,fracture,diastema and other unusual features of teeth as this can aid in implicating a suspect.
The measurement of mark constitutes “MATRIC ANALYSIS” and may be obtained using simple instruments such as venire caliper , or using computer software.
Measurements obtained from the bite marker are compared to that of the suspects dental model.
Metric analysis ideally should not be undertaken.Indipendantly but in conjugation with pattern association, which involves matching the configuration of bite injury to the arrangement of teeth on the suspect dentition
T he trend now a days has moved towards use of computer software programmers such as adobe photoshop,as suggested by Johannes and bowers.
MATERIALS Skin-body tissue foodstuffs other materials
MAC DONALD CLASSIFICATION-an etiological classification
1. Tooth pressure marks-marks produced on tissue as a result of direct application of pressure by teeth.
2. Tooth scrap markers-these are marks caused due to scrapping of teeth across the bitten material.
3. Tongue pressure markers-when sufficient amount of tissue is taken in to the mouth, the tongue presses it against rigid areas such as the lingual surfaces of teeth and palatal rugae.the marks thus left on the skin are referred to as “suckling’’ since there is a combination of sucking and tongue thrusting involved
WEBSTERS CLASSIFICATION- it is not uncommon to hold bite marks on food stuffs this is especially in cases of thief or robbery of home or shopping centers where there may be bite on food items during course of crime
1. Type1-the food items fractures readily with limited depth oftooth penetratione.g.; hard chocolate
Type 2- fracture of fragment of food item with considerable denudation of teeth eg:bite mark on a apple
Type3-complet or near complete denudation of food item with slide marks eg:cheese
BITE MARK INVESTIGATIONS Bite mark investigation should begin
with following questions. -is the injury a bite
mark????????????????? -if a bite, was it caused by human
teeth?? -was it caused by an adult or child??
Conclusion in bite mark analysis
Following comparison, a bite mark analysis may have one of the following concluding statements as suggested by Levine and ABFO
Definite bites-there are characteristics matches b/w the bite mark dimension pattern and that of suspect teeth
.
Probable bite-bite mark show some degree of specificity to the suspect teeth by virtue of a sufficient number matching point.
Possible bites-there are no characteristic matches to be absolutely certain. the similarities is non specific
Utility of dentures in identification
Identification of a body is made more difficult if some or all teeth are missing, but fortunately some dentures are marked and can be traced to a particular owner.
The material from which a denture has been made some times helps in identification.
The types of teeth fitted to the dentures and the standard of workmanship may also be useful points.
Although dentures are usually not marked for personal freedom, it is widely acknowledged that marking of dentures at constriction is a very cost effective method of identifying both living and dead person
Cast metal dentures, in contrast to all acrylic dentures are individually designed either by the dental surgeon or the dental technetium and are there for more helpful in identification procedure.
Lip printsclassification of lip prints
1. Diamond grooves2. Long vertical grooves3. Short vertical grooves4. Rectangular grooves5. Branching grooves
Utility of lip prints in identification
1. Though there are numerous variations and combination in lip prints, they can have few common patterns that have been classified by SUZUKI as 1 vertical
2 intersected 3 branched For classification the middle part of
lower lip is taken as study areas since its fragment is almost always visible.
The impression is visualized with the use of a magnifying lenses and the number of lines and furrows present, their length, branching of thickness and combination is noticed
In practice lip prints may be retrieved from the surface of cups,ciggarrette ends etc they are considered to be most important form of transfer evidence and are analogues to fingerprints
However ,since they disappear when lips are stretched and reappear when relaxed ,uniqueness of lip prints depends on the characteristic manner by which lip muscles relapse to produce a lip pattern
lip prints are used in detection work for personal identification as well as evidential use in legal procedure.
Lip prints sex differentiation
LIMITATION OF DENTAL IDENTIFICATION Condition and amount of dental
materials recovered depends upon circumstances surrounding depth and the care excised in its collection and transport burned teeth are usually very fragile and often disintegrated
In high impact accidents such as air crush damage can occur to teeth and jaws
Very fragile teeth and skelitanised material can be handled with out damage can be traced using a method which contains the impregnation of material with resin under reduced pressure followed by drying for twenty-four hours
In case where dental hard tissue are not recovered ashes may be required to recover as much dental material as possible
Rugoscopy
Forensic odontology
It is the branch of forensic science that deals with application of dental science to administration of law and explanation of complex subtitle of dental science to court
A forensic odontologist besides being a clinician as to observe , record ,gather preserve and intercept dental evidence and should be able to make it meaningful within legal context
It has following percepts1. Identification of an unknown
diseased person or multiple diseased people using dental evidence
2. Investigation of tooth or bite marks 3. Management of dental records with
legal requirements 4. Multiple application of forensic
odontology in other disciplines
Multiple identification of forensic odontology Roll of dental team in mass fatality
incidence –odontology technique has been made to identify victims of tsunami etc
Dental team plays an vital role in recovery postmortem , records , results can be convert through a dental section leader to identification chief on identification of the victims.
Role of dentistry in recognisation and reporting of human abuse.
Human includes child abuse and neglect domestic barriers, intimate partner violence and spouse abuse battery woman, elder abuse.
It is important for a dental professional to recognize signs and symptoms of this and understand the obligations to report and to eventually know the mechanisms for reporting the recognisation and reporting of neglect is also equal important
Role of forensic odontology in medical jurisprudence The investigations of illegal unregistered
practitioners and the promises from which they operate, involves the forensic odontologists,who is able to advice health and safety aspects for investigators and the status of prescription medicine recovered at the scene
Other issues that a forensic odontologists should require are consent to treat confidentially, risk minimization and evidence based practice etc
premortem
postmortem
Postmortem examination
The mechanism of this process involves comparing features of an unknown specimen to those of a known individual. The durability of human teeth makes this process possible
polygraph
An instrument used to detect lies Chelae polygraph and stocking diseftograph
are in common use. It makes a continuous record of BP Pulse
Respiration and electro dermal reaction change in response to stimuli
The emotion of fear results in a relative rise in BP along with slowing down of breathing and change in skin resistance
And experienced and competent polygraph examiner can correctly detect truth or lie in 80_90% of cases
Narcoanalysis
Administration of narcotic drugs subcutaneously/IV to induce subconciousness so that the subject is mentally incapable if inventing the falsehood that he/she may have used to conceal guilt.however,this technique is not very sensitive
Conclusion
Dental surgeons around the world can attribute significantly in solving crime, identifying victims, of mass disaster and understanding of pre historic man by giving due importance to the subject of forensic odontology.
the science needs necessary inputs in the form of format training research by the professionals, if it is to play an active role in criminology.utilisation of computers and newer technology such as the chip system, incorporation in teeth hold promise for the advancement of forensic odontology as an area of specialization.
Reference Text book of oral pathology Shafer's Text book of oral pathology Sanjay
seraph Text book of forensic medicine Wikipedia