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 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 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

epiphyseal fusion varies with sex and is typically complete by age 25 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 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)

3. Begin to add common fat deposits and underlying muscles Facial Reconstruction 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

Physical Characteristics 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.

(L-aspartic acid  D-aspartic acid with time) 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