title: Physicochemical and cell biological characterization of PMMA bone cements modified with additives to increase bioactivity.
abstract: Polymethylmethacrylate (PMMA) bone cement is the most widely used material in surgery to fix joint replacements in the bone. In this study, we propose a new approach to generate bioactive PMMA surfaces directly at the site of implantation by adding the amphiphilic molecule phosphorylated 2-hydroxyethylmethacrylate (HEMA-P) to commercial PMMA bone cement, both with or without addition of 1-5% soluble calcium and carbonate salts. The setting behavior as well as the mechanical properties, the bonding quality at the metal/cement interface, mineral deposition, and cellular response for different cement modifications were investigated in vitro. The addition of HEMA-P resulted in entirely positive effects with respect to proliferation and differentiation of osteoblast-like cells (SaOs-2) and a very tight contact at the metal/cement interface. No detrimental changes of other properties were detected. The additional incorporation of salts provoked an increased deposition of calcium phosphate minerals but no further improvement in SaOs-2 cell differentiation. A significant decrease in polarization resistance for cements with high salt content (5%) was attributed to debonding between metal and cement. The results suggest an improved clinical performance of PMMA/HEMA-P composites, which might be further enhanced by small amounts of the soluble salts.
authors.affiliation: Institute of Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, Dresden, Germany. Cornelia.Wolf-Brandstetter@tu-dresden.de
authors.forename: Cornelia
authors.initials: C
authors.lastname: Wolf-Brandstetter
authors.forename: Sophie
authors.initials: S
authors.lastname: Roessler
authors.forename: Sandra
authors.initials: S
authors.lastname: Storch
authors.forename: Ute
authors.initials: U
authors.lastname: Hempel
authors.forename: Uwe
authors.initials: U
authors.lastname: Gbureck
authors.forename: Berthold
authors.initials: B
authors.lastname: Nies
authors.forename: Susanne
authors.initials: S
authors.lastname: Bierbaum
authors.forename: Dieter
authors.initials: D
authors.lastname: Scharnweber
mesh_terms: D019643:Arthroplasty, Replacement; D001843:Bone Cements / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003470:Culture Media / Q000494:pharmacology; D006801:Humans; D007595:Joint Prosthesis; D008689:Methacrylates / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology; D010766:Phosphorylation; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011474:Prosthesis Design / Q000379:methods*; D012492:Salts / Q000737:chemistry; D013314:Stress, Mechanical
chemical_list: D001843:Bone Cements; D002130:Calcium Phosphates; D003470:Culture Media; D008689:Methacrylates; D012492:Salts; C005044:hydroxyethyl methacrylate; D019904:Polymethyl Methacrylate; C020243:calcium phosphate