Relationship of Tooth Wear to Chronological Age among Indigenous Amazon Populations

• Published in: PloS one Vol. 10; no. 1; p. e0116138
• Main Authors: Vieira, Elma Pinto, Barbosa, Mayara Silva, Quintão, Cátia Cardoso Abdo, Normando, David
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 20.01.2015; Public Library of Science (PLoS)
• Subjects: Adults; Age; Age determination; Age Factors; Animal behavior; Brazil - epidemiology; Brazil - ethnology; Chronology; Consent; Dentin; Dentistry; Dentition; Enamel; Environment; Female; Humans; Male; Orthodontics; Population; Populations; Regression analysis; River basins; Rivers; Studies; Teeth; Tooth Wear - epidemiology; Urban areas; Urban populations; Wear; Brazil
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0116138

In indigenous populations, age can be estimated based on family structure and physical examination. However, the accuracy of such methods is questionable. The aim of this cross-sectional study was to evaluate occlusal tooth wear related to estimated age in the remote indigenous populations of the Xingu River, Amazon. Two hundred and twenty three semi-isolated indigenous subjects with permanent dentition from the Arara (n = 117), Xicrin-Kayapó (n = 60) and Assurini (n = 46) villages were examined. The control group consisted of 40 non-indigenous individuals living in an urban area in the Amazon basin (Belem). A modified tooth wear index was applied and then associated with chronological age by linear regression analysis. A strong association was found between tooth wear and chronological age in the indigenous populations (p <0.001). Tooth wear measurements were able to explain 86% of the variation in the ages of the Arara sample, 70% of the Xicrin-Kaiapó sample and 65% of the Assurini sample. In the urban control sample, only 12% of ages could be determined by tooth wear. These findings suggest that tooth wear is a poor estimator of chronological age in the urban population; however, it has a strong association with age for the more remote indigenous populations. Consequently, these findings suggest that a simple tooth wear evaluation method, as described and applied in this study, can be used to provide a straightforward and efficient means to assist in age determination of newly contacted indigenous groups.