Forensic Odontology

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Forensic Odontology
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Forensic Odontology is

• The use of dentition in the identification of
  individuals by comparing the unique aspects of
  the victims teeth with predeath dental records
• Comparison of dentition with pattern injuries
  (bite marks) to identify suspects in crimes

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Dentition

• The whole complement of teeth

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Forensic Odontology

• One of the objectives of forensic odontology is
  to provide witness testimony in courts of law.
• Forensic dentists can analyze bite pattern
  injuries on victims or assailants and assist the
  court identifying the individual who did the
  biting.

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Dentition

• Everyone has two dentitions during life
• Primary dentition (childhood)
• 20 teeth
• Permanent dentition (adult)
• 32 permanent teeth

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Teeth

• Equally divided between two jaws
• Maxilla (upper jaw)
• Mandible (lower jaw)

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Adult Dentition (page 65)

• From midline to posterior
• Central incisor
• Lateral incisor
• Cuspid
• First bicuspid
• Second bicuspid
• First molar
• Second molar
• Third molar

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Tooth Structure

• Crown (visible)
• Root(s)
• 1-3, depending on tooth

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Death Identification

• The most reliable comparisions are made by using
  antemortem and postmortem dental x-rays

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Mass Disasters

• Four dental teams are necessary to identify bodies

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Team 1

• Sent to disaster scene
• Use grid search patterns to look for body parts,
  particularly jaw and tooth fragments throughout
  the entire scene.

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Team 2

• Remains at the morgue and performs the postmortem
  dental examinations
• Usually two dental professionals are assigned to
  each victim
• Dentist and dental hygienist or dental assistant

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Team 3

• Antemortem record team
• Contacts victims dentists and records dental
  findings

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Team 4

• In-putting the postmortem findings and antemortem
  data into computers
• Several software programs can be used to compare
  postmortem dental findings with antemortem dental
  data.
• Final identifications left to chief forensic
  dentist

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Team 5

• Chief forensic dentist
• Makes all dental identifications
• Relieve team members of duties when stress is
  causing mistakes
• Because only chief forensic dentist makes
  identifications, he is the only person to testify
  in court.

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Collection of Bite Mark Evidence

• Label with a ruler
• Swab for saliva
• Swab for DNA analysis
• Swab for microorganisms
• Photograph the bite mark
• Make impression of the bite mark
• Cast of teeth made from suspect to compare to
  impression

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Comparison of Evidence

• Evidence of saliva (amylase) proves it is a bite
  mark
• Finding positive association between the ABO
  blood type in the bite mark and the saliva of the
  suspect means the suspect cannot be excluded as
  the biter
• DNA keep suspect from being excluded
• Similar microorganisms in bite and suspect keep
  him from being excluded
• Comparison of casts and impressions

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Collection of Suspect Evidence

• Get search warrant or waiver
• Swab mouth of suspect for amylase, ABO blood
  grouping and DNA
• Swab gums for microbiology analysis
• Photograph suspects teeth and biting patterns
• Make impression of suspects teeth for the making
  of casts
• Record biting pattern in semi-solid material to
  compare with bite mark

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Terms

• Enamel
• The outer covering on the crown
• Antemortem
• Pre death
• Agonal
• Perimortem bite marks (within 5 minutes of death)

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Terms

• Amylase
• Enzyme group responsible for the catalysis of
  starches, specifically amylose and amylopectin.
  Found in human saliva