Dental caries prevalence as a product of agriculture and subsistence pattern at the Yean-ri site, South Korea

Abstract

Yean-ri human skeletal remains from South Korea have been dated to the fourth to seventh century AD. They have morphological similarities to immigrants of the Yayoi period excavated in northern Kyushu and Yamaguchi prefecture in Japan. The overall dental caries prevalence was 8.1% in the Yean-ri skeletal remains, indicating a much lower prevalence than that of most Yayoi immigrant skeletal remains from Japan, although similar to that of the Kofun people (8.3%) in Japan. There was no significant difference in the dental caries prevalence between the males and females of the same age group, but there were differences in the prevalence by age. The late middle age and elderly males and females had significantly higher dental caries prevalence than the early middle age males and females, indicating increased prevalence with age. Root caries prevalence tended to increase in old age. The percentage of root caries increased, accounting for 80% of all caries in Yean-ri human skeletal remains. Agriculture is believed to have arisen approximately 3,000 years ago in Korea. Therefore, agriculture was practiced during this period, but since the Yean-ri tumuli are from coastal areas, their diet may have retained a significant marine component. Additionally, caries prevalence was not very high in Nukdo human remains (ca. 2100-2000 BC) in Korea. We speculate that they maintained subsistence activities suitable for their environment despite their knowledge of agriculture. This hypothesis is supported by differences in the caries prevalence between excavation sites of the Yayoi and Kofun periods in Japan.