title: Composites of fluoroapatite and methylmethacrylate-based polymers (PMMA) for biomimetic tooth replacement.
abstract: Synthetic composite materials that mimic the structure and composition of mammalian tooth enamel were prepared by mixing fluoroapatite rods (diameter 2-3 μm, thickness about 0.5 μm) and methylmethacrylate (MMA), followed by polymerization either during or immediately after ultracentrifugation, using either a tertiary amine/radical initiator for polymerization at room temperature or a radical initiator for thermal polymerization. This led to mineral-rich composites (mineral content between 50 and 75 wt%). To enhance the mechanical stability and the interaction between fluoroapatite and polymer matrix, small amounts of differently functionalized MMA monomers were added to the co-monomer mixture. Another approach was the coating of the fluoroapatite rods with silica and the polymerization in the presence of a siloxane-functionalized MMA monomer. The hardness of the composites was about 0.2-0.4 GPa as determined by Vickers indentation tests, about 2 times higher than the polymer matrix alone. The composites had a good resistance against acids (60 min at pH 3, 37 °C).
authors.affiliation: Institute of Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitaetsstr. 5-7, D-45117 Essen, Germany.
authors.forename: Alwina
authors.initials: A
authors.lastname: Lübke
authors.forename: Joachim
authors.initials: J
authors.lastname: Enax
authors.forename: Karolin
authors.initials: K
authors.lastname: Wey
authors.forename: Helge-Otto
authors.initials: HO
authors.lastname: Fabritius
authors.forename: Dierk
authors.initials: D
authors.lastname: Raabe
authors.forename: Matthias
authors.initials: M
authors.lastname: Epple
mesh_terms: D000143:Acids / Q000737:chemistry*; D000180:Acrylic Resins / Q000138:chemical synthesis*; D000818:Animals; D001031:Apatites / Q000737:chemistry*; D040761:Biomimetic Materials / Q000138:chemical synthesis*; D003188:Composite Resins / Q000138:chemical synthesis*; D003343:Corrosion; D003743:Dental Enamel / Q000737:chemistry*; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011140:Polyurethanes / Q000138:chemical synthesis*; D012754:Sharks
chemical_list: D000143:Acids; D000180:Acrylic Resins; D001031:Apatites; C029012:Composite Dental Resin; D003188:Composite Resins; D011140:Polyurethanes; D019904:Polymethyl Methacrylate; C025105:fluorapatite