Objectives: To determine whether changes in strontium/calcium ratio in dental hard tissues reflect changes that are predicted to occur in response to marked dietary transitions, such as those experienced during the weaning period. Methods: Discrete micro-sampling of tooth enamel using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to examine changes in Sr/Ca in ground tooth sections from two juvenile baboons (Papio hamadryas anubis). The position of each sample was cross-referenced to incremental growth structures in the enamel, providing an age for the onset of enamel mineralization in each sample. Distribution maps for Sr/Ca were generated for each tooth and interpreted in relation to tooth crown geometry and incremental growth lines. Results: The introduction of Sr-rich foods is expected to result in an increase in Sr/Ca ratio. In the first baboon, Sr/Ca ratios are higher in later forming teeth, with statistically significant differences between successively forming teeth consistent with a gradual increase in Sr rich foods. In the second baboon, average Sr/Ca is higher in the earlier forming permanent molar than in the later forming incisor. The decrease in Sr/Ca may indicate the predicted increasing ability of the gastrointestinal tract to discriminate against Sr during development, as samples from the second baboon covered an older age range. Within teeth, the introduction of Sr-rich foods results in a reduction in the expected decrease in Sr/Ca ratio between successive sampling points from the enamel-dentine junction to the enamel surface. All three teeth in the first baboon show a reduction in the rate of change in Sr/Ca ratio approximately 12 weeks after birth, consistent with the first substantial intake of Sr-rich foods during the weaning process. Conclusion: LA-ICP-MS sampling permits longitudinal analysis of the weaning process in dental hard tissues. Funding provided by the University Research Committee of Emory University.
Division: British and Scandinavian Divisions Meeting
Meeting:2007 British and Scandinavian Divisions Meeting (Durham, England) Location: Durham, England
Year: 2007 Final Presentation ID:32 Abstract Category|Abstract Category(s):Mineralized Tissue
Authors
Dirks, Wendy
( Newcastle University, Newcastle upon Tyne, N/A, United Kingdom
)
Humphrey, Louise T.
( Natural History Museum, London, London, N/A, United Kingdom
)
Jeffries, Teresa E.
( Natural History Museum, London, London, N/A, United Kingdom
)
Dean, M. C.
( University College London, London, N/A, United Kingdom
)