title: Safety, osseointegration, and bone ingrowth analysis of PMMA-based porous cement on animal metaphyseal bone defect model.
abstract: Bone defects created after curettage of benign bone tumors are customarily filled with solid poly(methyl methacrylate) (PMMA) or other bone substitutes. In this study, we depicted a porous PMMA-based cement (produced by mixing sodium bicarbonate and citric acid) and evaluated the prospect of its clinic application. Cement samples were characterized by high-performance liquid chromatography (HPLC) coupled to mass spectrometry and its cytotoxicity evaluated in fibroblast cultures. Implantation in rabbits allowed the histologic analysis of bone, kidneys, and liver for toxicity and coagulation tests, and MRI images for hemostasis evaluation. Osseointegration was analyzed through radiography, microtomography (micro-CT), SEM, and histology of sheep specimens. Rabbit specimens were analyzed 1, 4, and 7 days after implantation of porous or solid bone cement in 6.0 mm femoral defects. Sheep specimens were analyzed 3 and 6 months after implantation or not of porous or solid cement in 15.0 mm subchondral tibial defects. The production process did not release any detectable toxic substance but slightly reduced fibroblast proliferation in vitro. Until 7 days after surgery, no local or systemic alterations could be detected in histology, or hematoma formation in histology or MRI. Sheep implants showed 6 mm linear ingrowth from the bone-cement interface and 20% bone ingrowth considering the whole defect area. Radiography, micro-CT, SEM, and histology confirmed these findings. We conclude that our porous PMMA-based cement is an attractive alternative treatment for bone defect filling that combines osseointegration and early weight bearing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 649-658, 2018.
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation of the Locomotor System, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Cimatti
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation of the Locomotor System, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Mariana Avelino Dos
authors.initials: MAD
authors.lastname: Santos
authors.affiliation: Department of Biology, Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Maria Sol
authors.initials: MS
authors.lastname: Brassesco
authors.affiliation: Department of Chemistry, Faculty of Philosophy, Sciences and Letters at Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Laura Tiemi
authors.initials: LT
authors.lastname: Okano
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation of the Locomotor System, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Wendell Monteiro
authors.initials: WM
authors.lastname: Barboza
authors.affiliation: Division of Radiology and Diagnostic Imaging, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Marcello Henrique
authors.initials: MH
authors.lastname: Nogueira-Barbosa
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation of the Locomotor System, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Edgard Eduard
authors.initials: EE
authors.lastname: Engel
mesh_terms: D000818:Animals; D001843:Bone Cements / Q000737:chemistry / Q000494:pharmacology*; D018786:Bone Substitutes / Q000737:chemistry / Q000494:pharmacology*; D016025:Bone Transplantation; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019343:Citric Acid / Q000737:chemistry / Q000494:pharmacology; D004195:Disease Models, Animal; D006801:Humans; D007668:Kidney / Q000187:drug effects; D008099:Liver / Q000187:drug effects; D008297:Male; D051379:Mice; D041681:NIH 3T3 Cells; D016348:Osseointegration / Q000187:drug effects*; D019904:Polymethyl Methacrylate / Q000737:chemistry / Q000494:pharmacology*; D016062:Porosity; D011817:Rabbits; D012756:Sheep; D017693:Sodium Bicarbonate / Q000737:chemistry / Q000494:pharmacology
chemical_list: D001843:Bone Cements; D018786:Bone Substitutes; D019343:Citric Acid; D017693:Sodium Bicarbonate; D019904:Polymethyl Methacrylate
keywords: PMMA; acrylic; bone cement; bone ingrowth; porosity; toxicity; tumor