Resumen de Estimating the preservation of tooth structures: towards a new scale of observation

Yannicke Dauphin, Stéphane Montuelle, Cécile Quantin, Pierre Massard

• For a better understanding of the fossilization processes and the paleoenvironmental records, knowing the state of preservation of fossil structures is essential. This paper presents how the analysis of tooth structures can be improved by using techniques increasing spatial resolution and accuracy, like atomic force microscopy (AFM). Micro- and nanostructural changes of the fresh and fossil dentine and enamel of two Suidae were thus observed with scanning electron (SEM) and atomic force microscopes. AFM and SEM show similar images for enamel and dentine in fresh teeth, whereas discrepancy occurs for fossil teeth. Both techniques show that dentine is modified by taphonomic and diagenetic processes, but only AFM is able to reveal that enamel is also altered, because AFM magnification and resolution are better than SEM ones. The apparent state of tissue preservation depends on the scale of observation and AFM, an analytical tool and a non-destructive/direct technique, allows a better understanding of the evolution of tissues at a nano-scale.