title: Modulation of porosity in apatitic cements by the use of alpha-tricalcium phosphate-calcium sulphate dihydrate mixtures.
abstract: Calcium phosphate bone cements are injectable biomaterials that are being used in dental and orthopaedic applications through minimally invasive surgery techniques. Nowadays, apatitic bone cements based on alpha-tricalcium phosphate (alpha-TCP) are of special interest due to their self-setting behaviour when mixed with an aqueous liquid phase. In this study, a new method to improve osteointegration of alpha-TCP-based cements is presented. This method consists in the modification of the cement's powder phase with different amounts of calcium sulphate dihydrate (CSD). The resulting hardening properties of the new biphasic cements are a combination between the progressive hardening due to the main alpha-TCP reactant and the progressive dissolution of the CSD phase, which render a porous material. It was observed that the maximum compressive strength of Biocement-H (45 MPa) decreased as the amount of CSD increased in the cement powder mixture ( approximately 30 MPa for 25 wt% of CSD). It was also observed that after complete dissolution of the CSD phase a porous apatitic structure appears with a mechanical compressive strength suitable for cancellous bone applications (10 MPa).
authors.affiliation: Division of Bioengineering and Biomaterials, Interdepartmental Research Group for the Applied Scientific Collaboration (IRGASC), Technical University of Catalonia (UPC), Avda. Diagonal 647, E-08028-Barcelona, Spain. enrique.fernandez@upc.es
authors.forename: Enrique
authors.initials: E
authors.lastname: Fernández
authors.forename: Maria Daniela
authors.initials: MD
authors.lastname: Vlad
authors.forename: Maria Montserrat
authors.initials: MM
authors.lastname: Gel
authors.forename: Jose
authors.initials: J
authors.lastname: López
authors.forename: Ricardo
authors.initials: R
authors.lastname: Torres
authors.forename: Juan V
authors.initials: JV
authors.lastname: Cauich
authors.forename: Marc
authors.initials: M
authors.lastname: Bohner
mesh_terms: D001031:Apatites / Q000032:analysis / Q000737:chemistry*; D001843:Bone Cements / Q000032:analysis / Q000737:chemistry*; D002130:Calcium Phosphates / Q000032:analysis / Q000737:chemistry*; D002133:Calcium Sulfate / Q000032:analysis / Q000737:chemistry*; D045424:Complex Mixtures / Q000032:analysis / Q000737:chemistry; D019245:Compressive Strength; D006244:Hardness; D008422:Materials Testing; D016062:Porosity; D011208:Powders; D013499:Surface Properties
chemical_list: D001031:Apatites; D001843:Bone Cements; D002130:Calcium Phosphates; D045424:Complex Mixtures; D011208:Powders; C485828:alpha-tricalcium phosphate; D002133:Calcium Sulfate