Ecology of dental disease.

Trace elements in the dental enamel of 43 prehistoric Indians from Illinois, Maryland and Virginia show concentration differences by age, sex and geographical locality. Sample areas on an incisor or first molar were blocked off with paraffin, washed twice with distilled water and etched 7 times with 6N HCl. An optical emission spectrophotometer was used to analyze the 9 samples, representing surface contamination and sequential enamel layers. Al, B, Ba, Cu, Fe, K, Mg, Mn, Na, Si, Sr, and Ti were present in most samples in micro or trace quantities; other elements were detected with less regularity. Comparisons of the 2 water washes with the 3 superficial, 4 deep and 7 total acid etches, suggest that during burial the residual inorganic portion of the enamel exchanged little or nothing with the soil. Enamel from archeological teeth may therefore be utilized in host factor studies in dental paleopathology. The Jy 50 Illinois Indians differ from the Potomac Creek, Virginia, Indians both in quantities of elements present and in internal sample variability. In each group, the sexes differ in 4 or more elements, both as to content and variability. Similarly, the older half of each sample differs from the younger. Patterns of sex and age difference are irregular, suggesting cultural differences, rather than physiological, in utilizing the environment during enamel-forming years. Enamel composition, as affected by differential environment utilization, may partially explain sex, age and geographical differences in dental pathology rates.