title: Cogrinding significance for calcium carbonate-calcium phosphate mixed cement. II. Effect on cement properties.
abstract: In the present study, we aim to evaluate the contribution of the cogrinding process in controlling calcium carbonate-dicalcium phosphate dihydrate cement properties. We set a method designed to evaluate phase separation, usually occurring during paste extrusion, which is quantitative, reliable, and discriminating and points out the determining role of cogrinding to limit filter-pressing. We show that solid-phase cogrinding leads to synergistic positive effects on cement injectability, mechanical properties, and radio-opacity. It allows maintaining a low (<0.4 kg) and constant load during the extrusion of paste, and the paste's composition remains constant and close to that of the initial paste. Analogous behavior was observed when adding a third component into the solid phase, especially SrCO(3) as a contrasting agent. Moreover, the cement's mechanical properties can be enhanced by lowering the L/S ratio because of the lower plastic limit. Finally, unloaded or Sr-loaded cements show uniform and increased optical density because of the enhanced homogeneity of dry component distribution. Interestingly, this study reveals that cogrinding improves and controls essential cement properties and involves processing parameters that could be easily scaled up. This constitutes a decisive advantage for the development of calcium carbonate-calcium phosphate mixed cements and, more generally, of injectable multicomponent bone cements that meet a surgeon's requirements.
authors.affiliation: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 4, allée Emile Monso, BP 44362, 31030 Toulouse Cedex 4, France.
authors.forename: Solène
authors.initials: S
authors.lastname: Tadier
authors.forename: Nadine Le
authors.initials: NL
authors.lastname: Bolay
authors.forename: Sophie Girod
authors.initials: SG
authors.lastname: Fullana
authors.forename: Sophie
authors.initials: S
authors.lastname: Cazalbou
authors.forename: Cédric
authors.initials: C
authors.lastname: Charvillat
authors.forename: Michel
authors.initials: M
authors.lastname: Labarrère
authors.forename: Daniel
authors.initials: D
authors.lastname: Boitel
authors.forename: Christian
authors.initials: C
authors.lastname: Rey
authors.forename: Christèle
authors.initials: C
authors.lastname: Combes
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D032701:Biomimetics; D001843:Bone Cements / Q000737:chemistry*; D002119:Calcium Carbonate / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D010006:Osteoblasts / Q000378:metabolism; D010316:Particle Size; D016062:Porosity; D011208:Powders; D013314:Stress, Mechanical; D013324:Strontium / Q000737:chemistry; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D001843:Bone Cements; D002130:Calcium Phosphates; D011208:Powders; C020243:calcium phosphate; D002119:Calcium Carbonate; D013324:Strontium