title: Compressive Residual Strains in Mineral Nanoparticles as a Possible Origin of Enhanced Crack Resistance in Human Tooth Dentin.
abstract: The tough bulk of dentin in teeth supports enamel, creating cutting and grinding biostructures with superior failure resistance that is not fully understood. Synchrotron-based diffraction methods, utilizing micro- and nanofocused X-ray beams, reveal that the nm-sized mineral particles aligned with collagen are precompressed and that the residual strains vanish upon mild annealing. We show the link between the mineral nanoparticles and known damage propagation trajectories in dentin, suggesting a previously overlooked compression-mediated toughening mechanism.
authors.affiliation: †Julius Wolff Institute, Charité-Universitätsmedizin, 13353 Berlin, Germany.
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Forien
authors.affiliation: ‡Materials Engineering, Berlin Institute of Technology, 10623 Berlin, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fleck
authors.affiliation: §European Synchrotron Radiation Facility, 38043 Grenoble, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Cloetens
authors.affiliation: †Julius Wolff Institute, Charité-Universitätsmedizin, 13353 Berlin, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Duda
authors.affiliation: ⊥Department of Biomaterials, Max-Planck-Institute of Colloids and Interfaces, 14424 Potsdam, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Fratzl
authors.affiliation: ¶Department of Materials Science and Engineering, Technion-Israel Institute of Technology, 32000 Haifa, Israel.
authors.forename: Emil
authors.initials: E
authors.lastname: Zolotoyabko
authors.affiliation: †Julius Wolff Institute, Charité-Universitätsmedizin, 13353 Berlin, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Zaslansky
mesh_terms: D003094:Collagen / Q000737:chemistry*; D003804:Dentin / Q000737:chemistry* / Q000648:ultrastructure; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D003094:Collagen
keywords: X-ray diffraction; apatite; diffraction nanotomography; mineralized-collagen-fibers; residual strain