title: Calcium carbonate-calcium phosphate mixed cement compositions for bone reconstruction.
abstract: The feasibility of making calcium carbonate-calcium phosphate (CaCO(3)-CaP) mixed cements, comprising at least 40% (w/w) CaCO(3) in the dry powder ingredients, has been demonstrated. Several original cement compositions were obtained by mixing metastable crystalline CaCO(3) phases with metastable amorphous or crystalline CaP powders in aqueous medium. The cements set within at most 1 h at 37 degrees C in atmosphere saturated with water. The hardened cement is microporous and exhibits weak compressive strength. The setting reaction appeared to be essentially related to the formation of a highly carbonated nanocrystalline apatite phase by reaction of the metastable CaP phase with part or almost all of the metastable CaCO(3) phase. The recrystallization of metastable CaP varieties led to a final cement consisting of a highly carbonated poorly crystalline apatite analogous to bone mineral associated with various amounts of vaterite and/or aragonite. The presence of controlled amounts of CaCO(3) with a higher solubility than that of the apatite formed in the well-developed CaP cements might be of interest to increase resorption rates in biomedical cement and favors its replacement by bone tissue. Cytotoxicity testing revealed excellent cytocompatibility of CaCO(3)-CaP mixed cement compositions.
authors.affiliation: CIRIMAT, UMR CNRS 5085, Equipe Physico-Chimie des Phosphates, ENSIACET, 118 route de Narbonne, 31077 Toulouse cedex 4, France. Christele.Combes@ensiacet.fr
authors.forename: C
authors.initials: C
authors.lastname: Combes
authors.forename: R
authors.initials: R
authors.lastname: Bareille
authors.forename: C
authors.initials: C
authors.lastname: Rey
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D001696:Biomechanical Phenomena; D001843:Bone Cements / Q000737:chemistry* / Q000378:metabolism*; D001842:Bone and Bones / Q000378:metabolism*; D002119:Calcium Carbonate / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D019245:Compressive Strength; D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D011208:Powders; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D001843:Bone Cements; D002130:Calcium Phosphates; D011208:Powders; C020243:calcium phosphate; D002119:Calcium Carbonate