Transcript Anthropology_and_Odontology ppt

Forensic Anthropology and
Odontology
Forensic Anthropology
study of human skeletal remains to determine sex, age,
race, and time and cause of death in an effort to identify
an individual
- includes newer topics of facial reconstruction and age
progression
- “anthros” is Greek for humankind or man, logos
means “the study of”
Types of Anthropology
• Physical Anthropology-A study of primate order past and present,
• Population genetics and Human evolution including skeletal biology and
human adaptation.
• Cultural Anthropology-Focuses on the study of cultural variation among
humans, collecting data about the impact of global economic and political
processes on local cultural realities.
• Linguistic Anthropology-A study of language variation across space and time,
The social uses of language, and Relationships between languages and
cultures.
• Archaeology-Study artifact and material remains of human societies.
• Analyze pollen, soil, seeds and insects found at excavation site.
• Forensic Anthropology- Forensic anthropology is the examination of human
skeletal remains for law enforcement agencies to determine the identity of
unidentified bones
Fields within Forensic Anthropology
• Osteology - specific study of bones.
• Dentition – study of tooth remains.
• Ethnobotany – study of pollen and plant
remains.
Information from Bones
• a. How person lived
• b. Debilitation illnesses (rickets, polio, healed
fractures)
• c. Right handed or left handed
• d. Clues to occupation
• e. Gender
• f. Age
• g. Cause of death
• h. PMI
• i. Stature
Education
• Most forensic anthropologists are specialists
in physical anthropology.
• Work in universities or museums
• Certification available from the American
Board of Forensic Anthropology
Interesting Books to Read
Skeletal anatomy
206 bones
Man = 12 lbs
woman = 10 lbs
Determination of Sex
1. Pelvis best
•
females have wider subpubic angle (>
90 degrees)
•
females have a wider sciatic notch
•
females have a broad pelvic inlet
Sex determination
•
The pelvis in men and women features subtle
differences, largely due to the fact that women
give birth. Bioarcheologists can use this disparity
to estimate and/or determine the sex of human
skeletal remains. This young individual was
probably female, because her pelvis exhibits
more female traits than male ones. One such
trait is the greater width of the sciatic notch (see
image); in males, it is narrower. Several other
female skeletons turned up in Puruchuco,
indicating that some Inca women fought
alongside their men in the Siege of Lima (“the
great Inca rebellion”).
Determination of Sex
2. Cranium second best
• Crests and ridges more
pronounced in males (A,
B, C)
• Chin significantly more
square in males (E)
• Jaw (I, E), mastoid
process wide and robust
in males
• Forehead slopes more in
males (F)
Determination of Sex
Other bones are not usually as good an indicator
regarding sex
Determination of Race
The cranium is the only reliable bone and, even
then, can only tell general category as below:
• Mongoloid (all of Asian decent and Native
American decent)
wider cheekbones, concave incisors,
width between eyes greatest
• Negro (everyone of African decent and West
Indian decent)
more prominent ridges, wider nasal opening
• Caucasian (all ‘white’ individuals)
narrow everything
• Race
Determination of Age from Bones
• Ages 0-5: teeth are best – forensic odontology
• Ages 6-25: epiphyseal fusion – fusion of bone
ends to bone shaft (permanent teeth)
epiphyseal fusion varies with sex and is typically
complete by age 25
• Ages 25-40: very hard
• Ages 40+: periodontal disease, arthritis,
breakdown of pelvis, occupational stress,
unique clues
Age
Bioarcheologists estimate the age of
child and subadult skeletons based
on the maturation of the skeleton
and the development of the teeth.
As seen here, the growth plate
(epiphysis) of her shin bone (tibia)
has not fused to the long bone
shaft. In most populations, these
bones fuse between the ages of 13
and 17. This girl was between 14
and 17 years of age when she
died—.
Determination of Age from Bones
Occupational stress wears
bones at joints
Surgeries or healed wounds
aid in identification
Determination of Stature from Bones
Long bone length (femur, tibia, humerus) is
proportional to height
There are tables that forensic anthropologists use.
For example:
Femur length
Predicted Height
41 cm
167 cm (5’6”)
50 cm
186 cm (6’1’)
Males: (1.88 x femur length in inches) + 32.01
Females: (1.945 x femur length in inches) + 28.70
Dating Human Skeletal Remains
Under the right conditions, bodies can be reduced
to a skeleton in as little as three weeks
Laboratory Tests
• Immunology tests can indicate if body is a few
months old or less
• Blood pigments last less than 10 years
• Identification of amino acids possible if less
than 100 yrs old (fluorescence)
• Percentage of nitrogen in bones (new is about
4.5%) – bones lose about 0.006% a year
• Carbon dating for bones centuries old
Determining Cause of Death
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Sharp force trauma (bone cut)
Blunt force trauma (broken bone)
Antemortem vs. postmortem breaks
Blunt Force Trauma
•
•
Many of the atypical burials recovered from the
Puruchuco cemetery (Lima, Peru) exhibit
perimortem (at or around the time of death)
trauma to their skulls, which likely caused or
contributed to their violent deaths. For this
young woman, severe blunt-force trauma
caused the fracture to the left side of her skull.
In her reconstructed skull, four fractures
radiate out from the site of impact, which is
also surrounded by concentric fractures. Her
skeleton showed no other injuries. The woman
obviously received a massive and lethal blow,
perhaps from an indigenous stone club.
Facial Reconstruction
1. Obtain skull
• Determine demographic information
(female, Caucasian, early 40s)
• Note unique features
(had lost all back teeth on
upper and lower jaw)
• Anything known about this individual?
(came to U.S. by boat in 1710
from Europe, died and buried in
NY around 1733)
Facial Reconstruction
2. Add tissue depth markers
•
Based on largely on sex and race
3. Begin to add common fat deposits
and underlying muscles
Facial Reconstruction
4. Add muscle to average
depth for race
5. Add skin, nose, ears
6. Add features related to age and
race (wrinkles, eye and hair color)
Facial Reconstruction
7. Add clothing etc appropriate for the
time period, religious affiliations, etc
Forensic Odontology
• identification of bite marks on victims
• comparison of bite marks with teeth of a suspect
• identification of unknown bodies through dental
records
• age estimations of skeletal remains
• victim identification through DNA analysis
Normal Adult Human Teeth
Forensic Odontology – Bite Marks
Physical Characteristics
• distance from cuspid to cuspid
• tooth alignment
• teeth width, thickness, spacing
• missing teeth
• wear patterns including chips and grinding
• dental history including fillings, crowns, etc.
Forensic Odontology – Age Determination
Neonatal Line – allows forensic
odontologists to determine if a child was
alive at birth
• Ratio of L-aspartic acid to D-aspartic acid (+/- 1.5 years)
(L-aspartic acid  D-aspartic acid with time)
• Gustafson’s Method – six signs of wear including dentin
density and transparency