The Effects of Experimental Whole-Body Burning on Histological Age-at-Death Estimation from Human Cortical Bone and Dental Cementum

Abstract

Whole-body donations (n = 6) were placed in various experimental fire-death scenarios to understand the histological effects of thermal alteration on bones and teeth. Midshaft samples of the femur, 6th rib, and metatarsal were removed from each donor pre- and post-burning to examine histomorphometric differences and test established age-at-death estimation methods. Dental samples were taken post-burning to test the applicability of dental cementum analysis for age-at-death estimation. Significant differences in osteon area or Haversian canal area between some pre- and post-burn samples were found although no patterns related to temperature or element were observable. The femoral age estimates across pre- and post-burn samples were 91% accurate across all donors. The point age estimates from the ribs compared to known age were significantly different (t(10) = 6.88, p < 0.001) with an average difference of −18.53 years. Dental age estimates of post-burn samples were not significantly different from the known donor age (t(3) = −0.74, p = 0.512) with an average difference of −3.96 years. Overall, the results of this study show that thermally altered remains can be used for histologic age-at-death analysis of cortical bone and dental cementum, within certain burning parameters.

Prevalence of drifting osteons distinguishes human bone

“…However, our "adult" category was broad, obscuring nuance in different age categories. Recent studies have found DOs highest in the 20-to 30-year age group, classified as "adult" in our study, but that DO osteon population density (OPD) decreased after age 30 [34,36]. The increase in DO OPD in juvenile and young adult humans may therefore be attributable to growth and development of peak bone mass, which, once achieved, tends to decline steadily into old age.…”

“…DOs have been posited as a distinguishing feature between human adult and juvenile bone [7,8]. Research indicates an inverse relationship between age and the presence of DOs, with younger individuals having a higher prevalence of DOs [32][33][34], although DOs are still documented in adult human bone [5,6,35,36]. Streeter [37] published a method of aging human juvenile ribs characterizing the presence of linear DOs as indicative of bone from adolescents.…”

“…The increase in DO OPD in juvenile and young adult humans may therefore be attributable to growth and development of peak bone mass, which, once achieved, tends to decline steadily into old age. However, DOs are still identified in humans into their nineties [36], so this method may still positively identify humans in any age category.…”

Bone color changes and interpretation of the temperature/duration of fire exposure to human remains in the forensic context

“…5.2 | Issue 2: Equating bone color with temperature assumes that the temperature of the fire is immediately and universally transferred to the bones in a fleshed body Unlike a furnace working on a small cleaned bone sample, burning a fully intact human body is a messy process in which various portions burn at different times and at different rates (Mavroudas et al, 2022). Temperatures within the fire are variable due to availability of external fuels, ventilation, moisture, and suppression efforts.…”

“…Unlike a furnace working on a small cleaned bone sample, burning a fully intact human body is a messy process in which various portions burn at different times and at different rates (Mavroudas et al, 2022). Temperatures within the fire are variable due to availability of external fuels, ventilation, moisture, and suppression efforts.…”