IADR Abstract Archives

Chemical compositions of enamel associated with early erosion and remineralisation

Objectives: Recent nanotechnological advancements have opened up opportunities for characterisation of early stages of erosive demineralisation and remineralisation of tooth structure, leading to a better understanding of the pathogenesis of dental erosion and preventive strategies. By using Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS), the aim of the present study was to assess the changes in chemical composition in human enamel following a single erosion episode and a subsequent application of a remineralising (CPP-ACP) paste.

Methods: Changes in the chemical compositions of flat, polished sound enamel specimens (n = 3) were determined at three different stages, including baseline, erosion in citric acid at pH 3 for 2 minutes, and remineralisation with a CPP-ACP paste for 5 minutes (Tooth Mousse, GC Asia, Tokyo, Japan). The specimens were then subjected to ToF-SIMS analysis at the end of each stage (ten measurements per stage) by generating both organic and inorganic mass spectral data obtained from the first 1-2 nm of the enamel surface. Principal Component Analysis (PCA) was used for multivariate analysis of the data at each stage of treatment for each specimen.

Results: A score plot of the first two Principal Components (i.e. components 1 and 2) showed different clusters for all three stages, with a greater variation in the surface chemistry for the CPP-ACP treated surface compared with baseline and erosion stages. The concentrations of Mg, Al, Si and Fe decreased with erosion but partially recovered after CPP-ACP treatment.

Conclusions: Our findings provide an insight into the fundamental mechanisms involved in early erosive demineralisation and remineralisation processes. The changes in the composition of metallic ions at different stages of treatment are probably associated with the changes occurring in the structure of hydroxyapatite crystals under eroded and remineralised conditions.

Acknowledgements: This study was supported by grants from Australian Dental Research Foundation Inc. and Dentsply Australia Pty Ltd.

Australian/New Zealand Division Meeting
2012 Australian/New Zealand Division Meeting (Denarau Island, Fiji)
Denarau Island, Fiji
2012

Scientific Groups
  • Ports, Emilija  ( University of Adelaide, Adelaide, N/A, Australia )
  • Ranjitkar, Sarbin  ( University of Adelaide, Adelaide, N/A, Australia )
  • Hall, Colin  ( University of South Australia, Mawson Lakes, N/A, Australia )
  • Denman, John  ( University of South Australia, Mawson Lakes, N/A, Australia )
  • Kaidonis, John  ( The University of Adelaide, Adelaide, , Australia )
  • Townsend, Grant  ( University of Adelaide, Adelaide, N/A, Australia )
    • Mineralized Tissue