Forensic Odontology

1. FORENSIC
ODONTOLOGY
(BITE MARK
ANALYSIS)

2. INTRODUCTION TO ODONTOLOGY
Forensic odontology is a unique field
that combines the skills of a specially trained
dentist with those of law enforcement. The
forensic dentist's primary duty is human
identification.
• They examine evidence from cases involving
violent crime, abuse, missing persons, and
disaster scenarios to identify victims or
suspects.

3. HISTORY OF FORENSIC ODONTOLOGY
• 66AD- First identification of body using teeth
(Lollia Paulina) .
• During the Revolutionary War , Paul Revere
became the First Forensic Dentist of the United
States because he identified the fallen
Revolutionary soldiers. 1849- Mass deaths at
Vienna Opera House Fire(Dental evidence was
First admitted in the US Court system)Bite Mark
Identification was first reported during the
Salem Witch trials (1692).

4. • The first case of identification known to
involve dentition in India occurred when
Raja Jayachandra Rathore of Canouj died on
the battlefield in 1191 and his body was
identified by his prosthetic anterior teeth.
• Father of Forensic Odontology:Dr Ascor
Amoedo, who is reputed as the father of
forensic odontology documented the first
case of dental identification in which more
individuals lost their lives in a disaster.

5. TEETH
• Teeth is made of enamel (hardest tissue of
the body) withstand trauma (decomposition,
heat degradation, water immersion, and
desiccation) better than other tissue of body.
• Teeth re source of DNA: dental pulp or a
crushed tooth can provide nuclear or
mitochondrial DNA that to help identify
person.
• In a 1999 meeting of the American Board of
Forensic Odontology, workshop participants
were asked to identify sets of bite marks. The
instructor found a 63% rate of false
identifications.

7. Dental evidence includes anything
relating to human dental anatomy or
derived from the oral environment
such as:
— Tooth shapes
— Metal restorations
— Skull and jawbone irregularities
— Skull fragments
Teeth are sometimes all that remains
of a body in catastrophic conditions.

8. WHAT IS A BITE MARK?
• A physical alteration in a medium
caused by the contact of teeth.
• A representative pattern left in an
object or tissue by dental
structures of an animal or human
Cutaneous bite-mark
• It is an injury in skin caused by
contacting teeth which shows the
representational patter of the oral
structure.

9. Bite marks have a high degree of variability and are
difficult to generalize.
• Common traits of bite marks are:
— Semi-circular
— Two opposing U-shaped arches separated by a
space at their bases
— A series of round bruises around the arches
— Possible small cuts

10. WHERE WE GET BITE-MARKS?
• Bites on human tissue may be observed in
violent incidents where the attacker may
bite the victim or the victim may bite the
attacker during defence response.
• Bite-marks may be observed in wax, from a
dental model indirectly from a photograph,
a scanned image of a dental model or food.

11. TYPES OF BITEMARKS

12. CHARACTERISTICS OF BITE-MARK
• BITE MARKS ARE LIKE FINGERPRINTS TO
Forensic Odontologists.
• Teeth may be considered as tools leaving
marks on skin, food ,wax etc. However,
there are often more characteristics
involved in the analysis of bite-mark
• There are class characteristics to be
considered such as which type of tooth
inflicted the bite. The biting surface of the
individual groups of teeth are related to
their function such as teeth that incise ,or
tear, or grind.

13. • In addition also seen are individual characteristics
such s rotations,fractures, missing or extra teeth.
• The size relationship of bite-marks, as described
by the dental arches, could relate to a child or
adult bite.
• Ability to open the mouth maximally may vary
from individual to individual.
• A human bite mark may be elliptical or circular in
shape and will display specific characteristics of
teeth.
• It can be U-shaped —shows that the biter has
open the mouth to a width

14. ANALYSIS OF BITE-MARK
• Bite-mark analysis is extremely complex, with many
factors involved in a forensic dentist’s ability to
determine the identity of the perpetrator.
• The movement of a person's jaw and tongue when
he or she bites contributes to the type of mark that is
left.
• Depending on the location of the bite, it's not typical
to find bite marks where both the upper and lower
teeth left clear impressions, usually one or the other
is more visible.
• If the victim is moving while being bitten, the bite
would look different from that inflicted on a still
victim.

15. • If an investigator sees something on a victim
that even resembles a bite the forensic
dentist must be called in immediately,
because bite marks change significantly
over time. For example, if the victim is
deceased, the skin may slip as the body
decays, causing the bite to move
• The first step in analyzing the bite is to
identify it as human. Animal teeth are very
different from humans teeth, so they leave
very different bitemark patterns.

16. • Next, the bite is swabbed for
DNA, which may have been left
in the saliva of the biter.
• Forensic dentists then ,Take
measurements of each
individual bite mark and record
it.They also require many
photographs because of the
changing nature of the bites.
Bruising can appear four hours
after a bite and disappear after
36 hours.

17. • The bite photography must be
conducted precisely, using rulers and
other scales to accurately depict the
orientation, depth and size of the bite.
The photos are then magnified,
enhanced and corrected for
distortions.
• Finally, bite marks on deceased victims
are cut out from the skin in the
morgue and preserved in a compound
called formalin, which contains
formaldehyde. Forensic dentists then
make a silicone cast of the bite mark.

18. • In addition, there are several
different types of impressions that
can be left by teeth, depending on
the pressure applied by the biter.
• A clear impression means that there
was significant pressure; an obvious
bite signifies medium pressure; and
a noticeable impression means that
the biter used violent pressure to
bite down.

19. FORENSIC RELEVANCE
• Bite-mark evidence can assist the justice
system to answer crucial questions about
interactions between people at the scene of
a crime .
• For individualization based on their unique
dentition pattern.
• Plays a crucial role in solving rape cases and
child abuse.
• Describe the violence level of crime.

20. THANK YOU !