Fourier transform infrared microspectroscopic investigation of the maturation of nonstoichiometric apatites in mineralized tissues: a horse dentin study

• Published in: Bone (New York, N.Y.) Vol. 29; no. 6; pp. 547 - 552
• Main Authors: Magne, D., Pilet, P., Weiss, P., Daculsi, G.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.12.2001; Elsevier Science
• Subjects: Animals; apatite; Apatite maturation; Apatites - chemistry; Biological and medical sciences; Carbonated apatite; Collagen; Dentin; Dentin - chemistry; FTIR microspectroscopy; Horses; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Microscopy, Electron, Scanning; Mineralization; Osteoarticular system. Muscles; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Spectroscopy, Fourier Transform Infrared - methods; Dentin; FTIR microspectroscopy; Apatite maturation; Mineralization; Collagen; Carbonated apatite; Fourier transformation; Interaction; In vitro; Ripening; Infrared spectrometry; Vertebrata; Mammalia; Animal; Horse; Apatite; Perissodactyla; Carbonates; Tooth; Ungulata; Physicochemical properties
• ISSN: 8756-3282; 1873-2763
• DOI: 10.1016/S8756-3282(01)00609-3

Fourier transform infrared microspectroscopy (FTIRM) was used to study carbonated apatite/collagen interactions and maturation in horse secondary dentin. Unlike human dentin, this model contains no peritubular material around the odontoblastic processes and is thus quite similar to bone in composition, but not subject to tissue turnover. Crystals close to the mineralization front were very immature, showing high HPO 4 and very low CO 3 levels. Carbonate ions were located essentially in very labile, reactive environments, probably on the crystal surface. Removal of some of the HPO 4 ions from crystals during maturation was linked to an increase in total carbonate content. The CO 3 ions in labile environments decreased, probably after incorporation into more organized regions of the lattice. However, this increase of total carbonate content was associated with greater mineral crystallinity, confirming findings in other studies of synthetic apatite maturation in vitro. The good correlation between these results and those of in vitro experiments suggests that crystal maturation is essentially due to physicochemical processes and that the organic matrix controls only crystal size, multiplication, and/or organization.