Using LEXT laser-scanning confocal microscopy to identify enamel surface defects in archaeological caribou dentition: A pilot study from Southern Baffin Island, Nunavut, Canada

Abstract

Dental enamel defects have been used extensively in past human populations to elucidate patterns of health and physiological disruption (often simply referred to as stress). These defects are most commonly assessed through visual examination and used to infer such information as the frequency and age at occurrence of stress events. However, a microscopic approach makes it possible to more consistently identify patterns of growth and growth disruption in greater detail than that possible with traditional macroscopic techniques. Such microscopic studies are being increasingly explored in bioarchaeology, but this area of investigation has not seen extensive application to zooarchaeological material. Consequently, enamel defects in general have not been integrated as heavily in this field. A species of particular importance within the modern context of climate change is the barren-ground caribou (Rangifer tarandus groenlandicus). This species has been a crucial species to the human populations throughout the Arctic for thousands of years, and herd fluctuations have in the past shaped the human experience. The study of past stress in these populations could provide significant historical insight into herd patterns, which would have impacted subsistence and mobility patterns, and traditional use of these animals among both past and contemporary human populations. This paper presents the results of a pilot study using the Olympus LEXT Laser-Scanning Confocal Microscope OLS4000 to evaluate enamel growth in an archaeological caribou tooth from the LdFa-1 site (a large caribou hunting site located in the deep interior of southern Baffin Island). Our study demonstrates the potential of this technology to capture enamel surface microstructures and to provide greater insight into the fine patterns of growth arrest within this zooarchaeological context.