Intertooth patterns of hypoplasia expression: Implications for childhood health in the Classic Maya collapse
✍ Scribed by Wright, Lori E.
- Book ID
- 101214410
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 218 KB
- Volume
- 102
- Category
- Article
- ISSN
- 0002-9483
No coin nor oath required. For personal study only.
✦ Synopsis
Enamel hypoplasias, which record interacting stresses of nutrition and illness during the period of tooth formation, are a key tool in the study of childhood health in prehistory. But interpretation of the age of peak morbidity is complicated by differences in susceptibility to stress both between tooth positions and within a single tooth. Here, hypoplasias are used to evaluate the prevailing ecological model for the collapse of Classic Period Lowland Maya civilization, circa AD 900. Hypoplasias were recorded in the full dentition of 160 adult skeletons from six archaeological sites in the Pasio ´n River region of Guatemala. Instead of constructing a composite scale of stress experience, teeth are considered separately by position in the analysis. No statistical differences are found in the proportion of teeth affected by hypoplasia between ''Early,'' Late Classic, and Terminal Classic Periods for anterior teeth considered to be most susceptible to stress, indicating stability in the overall stress loads affecting children of the three chronological periods. However, hypoplasia trends in posterior teeth may imply a change in the ontogenetic timing of more severe stress episodes during the final occupation and perhaps herald a shift in child-care practices. These results provide little support for the ecological model of collapse but do call to attention the potential of posterior teeth to reveal subtle changes in childhood morbidity when consideredindividually.AmJPhysAnthropol102:233-247,1997 r 1997Wiley-Liss,Inc.
Enamel hypoplasias are a common focus of bioarchaeological research that addresses health transitions in prehistory. These dental defects are particularly useful because they record nutritional and health stresses during childhood, a crucial period of life. Childhood health is directly linked to the demographic structure of a society and to population processes at large. Because subadult remains are often underrepresented in archaeological skeletal series, hypoplasias provide a unique record of childhood stress experience observable in adult skeletons.
Enamel is laid down first as a protein matrix secreted by ameloblasts in the dental papilla. Hydroxyapatite crystals then form in this matrix along flow lines generated by ameloblastic secretions. The resulting enamel mineral has a prismatic structure; each prism records the paths taken by four adjacent ameloblasts over their secretory lives (Osborn, 1973). Nutritional or disease stresses that disrupt the ameloblastic secretory rate result in reduced enamel thickness. As amelogenesis commences at the tooth cusp and progresses cervically, this disruption is permanently registered as a ring or circumferential groove of deficient or