US EPA

751464 

Journal Article 

The nano-morphological relationships between apatite crystals and collagen fibrils in ivory dentine 

Jantou-Morris, V; Horton, MA; Mccomb, DW 

2010 

Yes 

Biomaterials
ISSN: 0142-9612
EISSN: 1878-5905 

31 

19 

5275-5286 

English 

20381860 

10.1016/j.biomaterials.2010.03.025 

WOS:000278466100026 

In this work, analytical transmission electron microscopy (TEM) was used to study the nanostructure of mineralised ivory dentine, in order to gain a clearer understanding of the relationship between the organic (collagen fibrils) and inorganic (calcium phosphate apatite crystals) components. Thin sections prepared by both focused ion beam (FIB) milling and ultramicrotomy, in the longitudinal and transverse planes, were investigated using electron energy-loss spectroscopy (EELS) in a monochromated field-emission gun scanning TEM (FEI Titan 80-300 FEGSTEM). Both low- and core-loss spectroscopy were used in the investigation, and the signals from phosphorous, carbon, calcium, nitrogen and oxygen were studied in detail. A combination of HAADF (high-angle annular dark-field)-STEM imaging and EELS analysis was used for simultaneous acquisition of both spatial and spectral information pixel by pixel (spectrum imaging). Across the collagen D banding in longitudinal sections, the relative thickness of the bright bands was significantly higher than that of the dark bands. Core-loss spectroscopy showed that the bright bands were richer in apatite than the dark bands. However, no ELNES variation was observed across the D banding. In transverse sections, significant changes in the carbon edge fine structure were observed at the interface between the extra- and intra-fibrillar regions.