Terminology
• Odontology –dentistry; the study of the teeth
• Dentition – the complement of teeth of an individual
• Bite Marks – the pattern left by teeth in human tissue of
inanimate objects
• Negligence – the failure to treat the patient at the highest
level of care and competency
• Prognosis – the predicted outcome of a patient’s condition
• Maxilla – upper jaw
• Mandible – lower jaw
• Enamel – the outer covering of the tooth
• Perimortem – at or around the time of death
• Postmortem – after death
• Antemortem – pre-death
Overview
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Introduction
History
Dental Training
Expert Witness Testimony
Body Identification
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Dentition Descriptions
Postmortem Examination and Records
Antemortem Record and Examination
Record Comparison and Reporting
• Bite Mark Analysis
• Bite Mark Recognition
• Collection and Comparison of Bite Mark Evidence
I. Introduction
1. Forensic Odontology is the application of the arts
and sciences of dentistry to the legal system.
2. Three (3) main areas:
1. Use of dentition in the identification of
individuals by comparing teeth with predeath
dental records and the use of teeth as a source for
DNA
2. Comparison of dentition with pattern injuries in
human tissue or inanimate substances
3. Analysis of negligence, standard of care issues,
and injury in malpractice cases.
How is Odontology used to
Solve Crimes?
• http://www.youtube.com/watch?v=D
KeEbVLZNWc
Body Identification by Dental
Means
• Dentition Descriptions
• Post mortem
Examination and
Record
• Ante mortem record
and examination
• Record Comparison
and reporting
• Forensic Dentistry in
mass disaster
Dentition Descriptions
• Every Individual has 2
dentitions in their life:
• Primary (20)
• Permanent (32)
• The teeth are divided
between 2 jaws
• Maxilla
• Mandible
• Primary Dentition – A-T
• Permanent uses #1-#16
(upper), and #17-#32 lower
Structure of the tooth
• All teeth are divided
into a crown, and a
root.
• Crown is covered
with enamel.
• In the center of the
tooth is the pulp or
nerve tissue----DNA
source
Post mortem Examination and
Record
• Begins with access to
dentition
• May be done in place (in
situ)
• Dentition may need to be
removed
• If the jaw is removed, it is
first soaked in hydrogen
peroxide…
• Statements are made
whether teeth are erupted,
restored, and with what
filling material.
• Also gum and
periodontal disease
• X-rayed if possible
Ante mortem record and
examination
• The accuracy and
completeness of a
persons dental records
allow a dentist to make
a positive identity with
reasonable certainty.
• Next of kin
• Personal effects
• Once a person has gone
missing their dental
records are entered into
a national database
Record Comparison and
reporting
• If the postmortem and ante mortem data are
complete, the comparison and identification
process is straightforward.
• Each tooth of the post mortem record is compared
to the same tooth in the ante mortem record.
• A statement is made…
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No inconsistencies
Explainable inconsistencies
Unexplainable inconsistencies
Undeterminable
• The most reliable method is X-rays
Forensic Dentistry in Mass
Disaster
Forensic Dentists face several
challenges in Mass Disaster
cases:
•Dismemberment and
alterations of dentition
•Victims can be from other
countries and obtaining ante
mortem records is difficult
•The amount of stress in
dealing with these situations
is debilitating
Bite Mark Analysis
• Recognition
• Most often seen in cases of
abuse, rape, murder
• In order to be used as
evidence:
• Recognizable bite pattern
• Know what to do with the
evidence
• The first and second
bicuspids are rarely
involved in bite marks
Bite Mark
Recognition…..
• Bite marks in human tissue depends on:
• The tissue bitten
• Muscle or connective tissue has a more
distinct outline compared to fatty tissue
• The biting force
• Defensive or aggressive bite marks tend
to be less distinct and may show tearing
• The resistance to biting by the victim
• The more compliant the victim, the more
defined the mark
• Bite marks found on deceased victims are
more useful than on living victims.
• On a living victim is must be collected with
in 8 hours
Using Bite Marks to Determine
Time of Death
• 1: Ante mortem bite marks – injury
inflicted while the heart is still
beating will produce bruising
around the patterns and will
usually diffuse
• 2: Peri mortem Bite marks – (w/in
5 minutes) injury inflicted at the
time the heart stops will produce
well defined bruising
• 3: Postmortem bite marks: the
heart is not beating and the blood
has coagulated produces well
define indents and no bruising
10 days later
Collection Of Evidence
• Bite marks can only be
used as evidence if all
data is carefully
collected.
• Photographed with ruler
• Swabbed for saliva and
DNA
• Impressions are made
• Cast of assailants
(suspect) teeth
• Metric analysis
Comparison
• The last step in bite
mark analysis is the
comparison of the
bite mark with the
suspects dentition.
• Saliva is compared
(amylase, ABO blood type,
DNA)
• Bite planes
• Photographs
• Metric Analysis