Raman investigation of calcium carbonate bone substitutes and related biomaterials.

The interaction between biomaterials used in surgical procedures and the host bone is not yet perfectly understood. It appears that these problems may have been encountered because of insufficient characterisation of the basic component used in the synthesis of such biomaterials. Calcium carbonate (CaCO3) is interesting for bone filling or regeneration procedures because of its resorbability. The aim of this work is to compare different CaCO3 biomaterials and their basic source with the help of microRaman spectroscopy. Bionacre and Biocoral are analysed. The main bands of carbonate internal modes are observed around 1084-86 and 704-12 cm-1. In the lattice modes region, for both Biocoral and synthetic aragonite, two bands at 206 and 155 cm-1 are observed. The eggshell, oyster shell and synthetic calcite samples exhibit bands at 281 and 155 cm-1. Three bands are present at 280, 206 and 155 cm-1 on the Bionacre sample. The 206 and the 280 cm-1 bands are due to aragonite and calcite forms respectively. Therefore it appears to be a mixture of aragonite and calcite whereas Biocoral is pure aragonite. Additional Raman investigations should be of great interest in evaluating the structural modifications and their influence on the biological behaviour of these biomaterials. Lity index, the percentage of prematurity and of low birth weight are the indices of national health status.