title: Effects of MgO-CaO-P2O5-Na2O-based additives on mechanical and biological properties of hydroxyapatite.
abstract: In this research, we improved densification, hardness, and compression strength of synthetic hydroxyapatite (HAp) ceramics by introducing small quantities of MgO-CaO-P(2)O(5)-Na(2)O-based sintering additives. Biological properties of HAp were not altered by this procedure. Phase analyses were performed by using a Philips Xpert fully automated diffractometer with Co K-alpha radiation to understand the influence of additives on phase purity in the final products. All compositions were characterized at green and sintered densities to understand the influence of additives on densification. Some of the compositions showed >40% increase in Vickers microhardness compared with pure HAp processed under the same conditions. Improvement in compression strength was also detected in some compositions. In vitro biological testing used a modified human osteoblast cell line to test biocompatibility, cell attachment, and cell proliferation. All these compositions were nontoxic and biocompatible. Our results indicate that MgO-CaO-P(2)O(5)-Na(2)O-based sintering additives can be used to improve both mechanical and biological properties of HAp ceramics.
authors.affiliation: School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164, USA. samar@mail.ucf.edu
authors.forename: S J
authors.initials: SJ
authors.lastname: Kalita
authors.forename: D
authors.initials: D
authors.lastname: Rokusek
authors.forename: S
authors.initials: S
authors.lastname: Bose
authors.forename: H L
authors.initials: HL
authors.lastname: Hosick
authors.forename: A
authors.initials: A
authors.lastname: Bandyopadhyay
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism; D017610:Calcium Compounds / Q000737:chemistry*; D002460:Cell Line; D002516:Ceramics / Q000737:chemistry / Q000378:metabolism; D019245:Compressive Strength; D006244:Hardness; D006801:Humans; D006882:Hydroxyapatites / Q000737:chemistry* / Q000378:metabolism; D008277:Magnesium Oxide / Q000737:chemistry*; D008422:Materials Testing; D019563:Mechanics; D010006:Osteoblasts / Q000166:cytology / Q000502:physiology; D010087:Oxides / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D017670:Sodium Compounds / Q000737:chemistry*; D013718:Tensile Strength; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D017610:Calcium Compounds; D006882:Hydroxyapatites; D010087:Oxides; D017680:Potassium Compounds; D017670:Sodium Compounds; C096707:sodium oxide; D008277:Magnesium Oxide; C068440:potassium oxide; C016538:lime