Age determination using the human skeleton

1. Age determination using the human skeleton Forensic Anthropology 11-21-2008

2. Age determination at death • Methods based on • Skeletal growth and dentition • Subadults (fetus to young adult) • Based on ossification and fusion • Deterioration of skeleton with advancing age • Adults • Not as accurate

3. Age determination • Primary and secondary ossification centers grow together to form larger segments (epiphyses, diaphyses) • Teeth grow by tissue deposit in open areas called crypts

4. Age determination of subadults • Long bone lengths – up to time of birth • After birth, less reliable • Union of primary ossification centers • Follows a rough schedule • Recovery unlikely • Fontanels most useful • Tooth formation/eruption • Deposition goes from cusp to root • Epiphyseal union

5. Age determination of subadults • Fontanels • Frontal (anterior) • Sphenoid • Mastoid • Occipital (posterior) • Table 9.2

6. Age determination of subadults • Sequences of dental eruption • ~ 1 year, first deciduous teeth • By 4 years old, all deciduous teeth erupted • 6 years, first permanent molar • 8 years, permanent incisors • 12 years, no deciduous teeth left, 2nd molar erupted • By 18-21 all 32 permanent teeth present, fully formed and occluding

7. Age determination of subadults • Epiphyseal union • Most useful for ages 10-25 years • Stages: non union, unfused, fused, obliterated • Figure 9.16 • Epiphyses • Long bones: 2+ each • Ribs: 2 each • Vert C3 – T12: 5 each • Vert L1 – L5: 7 each

8. Age determination of adults • Pubic symphasis • Auricular surface • Rib ends • Cranial sutures • Vertebrae

9. ADULTS – Suture closures – not a consistent rate of closure, best for estimation only Sagittal closes first – posterior to anterior Coronal next Lambdoidal last Squamousal – RARELY closes Lapsed union – sutures not fully closed, but bulges at the edges Granular pits/pacchionian depressions increase on interior of skull toward midline Age and the adult skull (p.44)

10. Dental aging with adult teeth • Dental attrition (wear) most useful in paleoanthropology and archaeology populations • What changed? • Processed food, dental care

11. Age and the ribs (p.74) • Bone to cartilage interface changes with age (sternal end) • Cartilage gradually ossifies • Stages 0-8 • V-shaped concavity forms and deepens • Edges loose smoothness, become sharp • Wavy interior surface smoothes out • s/I surfaces project, advance to form crab-claw edges

12. Age and the spine (p.88) • Vertebral bodies – 4 stages • Appearance and changes of the epiphyseal rings • Obliteration of undulations • Presence/absence of line of fusion • Increasing porousness of bone • Osteophytes increase with advanced age • Sacrum – transverse line between S1 and S2 fuses in the mid-twenties or later

13. Age and the adult pelvis • Auricular surface (p.127) • Apex • Demifaces • retroauricular areas

14. Age and the adult pelvis • Pubic symphysis (p.123-125) • Pubic face: surface undulations • Ridges and furrows/flat and granular/pitted and eroded • Ventral and dorsal margins: changing shape of the edge surfaces • Upper and lower extremities: erosion and lipping • Ossific nodules

15. Age determination • Histological methods • Dental changes • Other methods