SSW researchers are working with members of the Anthropology department (Andrew Nelson and Emy Roberge) to look at the internal structures of 500 year old sacrificial virgin mummy teeth. We examined thin-sections of two teeth from a cemetery associated with a female institution in Farfán on the North Coast of Peru during the Inca Empire (A.D. 1450-1532). Examining the internal structure of teeth allowed for the observation of empty patches due to a mineralization defect in dentin, the inner tissue of the tooth. This defect, called interglobular dentin (IGD), is associated with a deficit in vitamin D during tooth formation in childhood. Once formed, the structure of teeth does not change and therefore they keep a record of the life of an individual.
For this work we used variable pressure mode within the SEM because we did not want to coat these 500 year old samples with a conductive coating, such as carbon or gold. The below image is a variable pressure SEM image of the same tooth as above. This image is pretty neat because it’s super low magnification (usually SEMs are used for high magnification work and this highlights the versatility of the technique), and captured in variable pressure mode using an imaging mode called UVD:
From here we captured a series of higher magnification images showing the IGDs within the teeth.