title: Low-modulus PMMA bone cement modified with castor oil.
abstract: Some of the current clinical and biomechanical data suggest that vertebroplasty causes the development of adjacent vertebral fractures shortly after augmentation. These findings have been attributed to high injection volumes as well as high Young's moduli of PMMA bone cements compared to that of the osteoporotic cancellous bone. The aim of this study was to evaluate the use of castor oil as a plasticizer for PMMA bone cements. The Young's modulus, yield strength, maximum polymerization temperature, doughing time, setting time and the complex viscosity curves during curing, were determined. The cytotoxicity of the materials extracts was assessed on cells of an osteoblast-like cell line. The addition of up to 12 wt% castor oil decreased yield strength from 88 to 15 MPa, Young's modulus from 1500 to 446 MPa and maximum polymerization temperature from 41.3 to 25.6°C, without affecting the setting time. However, castor oil seemed to interfere with the polymerization reaction, giving a negative effect on cell viability in a worst-case scenario.
authors.affiliation: Department of Engineering Sciences, Division of Applied Materials Science, The Ångström Laboratory, Uppsala University, Sweden.
authors.forename: Alejandro
authors.initials: A
authors.lastname: López
authors.forename: Andreas
authors.initials: A
authors.lastname: Hoess
authors.forename: Thomas
authors.initials: T
authors.lastname: Thersleff
authors.forename: Marjam
authors.initials: M
authors.lastname: Ott
authors.forename: Håkan
authors.initials: H
authors.lastname: Engqvist
authors.forename: Cecilia
authors.initials: C
authors.lastname: Persson
mesh_terms: D001843:Bone Cements / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D002368:Castor Oil / Q000737:chemistry / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D019245:Compressive Strength / Q000187:drug effects; D055119:Elastic Modulus / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008422:Materials Testing; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D010968:Plasticizers / Q000737:chemistry / Q000494:pharmacology; D019904:Polymethyl Methacrylate / Q000737:chemistry* / Q000494:pharmacology; D013499:Surface Properties / Q000187:drug effects
chemical_list: D001843:Bone Cements; D020099:Coated Materials, Biocompatible; D010968:Plasticizers; D002368:Castor Oil; D019904:Polymethyl Methacrylate