Forensic Anthropology and Odontology

1. Forensic Anthropology and Odontology

2. Forensic Anthropology • the study of human skeletal remains to determine sex, age, race, and time of death in an effort to identify an individual • Definition has been expanded to include these subtopics: • forensic taphonomy – interpretation of outdoor death scenes • forensic archaeology – recovery of scattered or buried remains • newer topics of facial reconstruction and age progression • “Anthros” is Greek for humankind or man and logos means “the study of.”

3. Forensic Anthropology Pictures courtesy of Charles Comer

4. Determination of Sex • Pelvis best • females have wider subpubic angle • females have a wider sciatic notch • females have a broad pelvic inlet • Females have a larger pelvic brim

5. Determination of Sex • Pelvis best • females have wider subpubic angle • females have a wider sciatic notch • females have a broad pelvic inlet

6. 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)

7. Determination of Sex Other bones are not usually as good an indicator regarding sex

8. Determination of Race • The cranium is the only reliable bone and, even then, can only tell general category as below: • ‘Mongoloid’ (all of Asian and Native American decent) • wider cheekbones, concave incisors, • width between eyes greatest • ‘Black’ (everyone of African and West Indian decent) • more prominent ridges, wider nasal opening • ‘White’ (Caucasian and Hispanic decent) • narrow everything

9. 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 • epiphyseal fusion varies with sex and is typically complete by age 25 • Ages 25-40: very hard, can use pubic symphysis • Ages 40+: periodontal disease, arthritis, breakdown of pelvis, occupational stress, unique clues

10. Determination of Age from Bones Occupational stress wears bones at joints Surgeries or healed wounds aid in identification

11. 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 lengthPredicted 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

12. 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

13. 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)

14. Facial Reconstruction • Add tissue depth markers • Based on largely on sex and race 3. Begin to add common fat deposits and underlying muscles

15. 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)

16. Facial Reconstruction 7. Add clothing etc appropriate for the time period, religious affiliations, etc

17. Facial Reconstruction

18. Photo of 2.5 year old male abducted by a family member Age Progression Age progression drawing using parents and siblings as a guide. It had been 15 years since the abduction so the subject was aged to 18 years of age.

19. Age Progression Drawing led to tips and identification of the victim Age progression drawing using parents and siblings as a guide. It had been 15 years since the abduction so the subject was aged to 18 years of age.

20. Age Progression Drawing led to tips and identification of the victim Age progression drawing using parents and siblings as a guide. It had been 15 years since the abduction so the subject was aged to 18 years of age.

21. 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

22. Normal Adult Human Teeth

23. 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.

24. 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 (+/- 4 years)