title: Silicon Nitride: A Synthetic Mineral for Vertebrate Biology.
abstract: The remarkable stoichiometric flexibility of hydroxyapatite (HAp) enables the formation of a variety of charged structural sites at the material's surface which facilitates bone remodeling due to binding of biomolecule moieties in zwitterionic fashion. In this paper, we report for the first time that an optimized biomedical grade silicon nitride (Si3N4) demonstrated cell adhesion and improved osteoconductivity comparable to highly defective, non-stoichiometric natural hydroxyapatite. Si3N4's zwitterionic-like behavior is a function of the dualism between positive and negative charged off-stoichiometric sites (i.e., N-vacancies versus silanols groups, respectively). Lattice defects at the biomaterial's surface greatly promote interaction with positively- and negatively-charged functional groups in biomolecules, and result in the biologically effective characteristics of silicon nitride. These findings are anticipated to be a starting point for further discoveries of therapeutic bone-graft substitute materials.
authors.affiliation: Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, 606-8126 Kyoto, Japan.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pezzotti
authors.affiliation: Amedica Corporation, 1885 West 2100 South, Salt Lake City, 84119 Utah, USA.
authors.forename: Bryan J
authors.initials: BJ
authors.lastname: McEntire
authors.affiliation: Amedica Corporation, 1885 West 2100 South, Salt Lake City, 84119 Utah, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Bock
authors.affiliation: Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, 606-8126 Kyoto, Japan.
authors.forename: Marco
authors.initials: M
authors.lastname: Boffelli
authors.affiliation: Department of Medical Engineering for Treatment of Bone and Joint Disorders, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0854, Japan.
authors.forename: Wenliang
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Ceramic Physics Laboratory, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, 606-8126 Kyoto, Japan.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Vitale
authors.affiliation: Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Puppulin
authors.affiliation: Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Adachi
authors.affiliation: Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Dental Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Narisato
authors.initials: N
authors.lastname: Kanamura
authors.affiliation: Amedica Corporation, 1885 West 2100 South, Salt Lake City, 84119 Utah, USA.|Department of Orthopaedic Surgery, University of Missouri, Columbia, 65212 Missouri, USA.
authors.forename: B Sonny
authors.initials: BS
authors.lastname: Bal
mesh_terms: D001861:Bone Regeneration / Q000187:drug effects*; D018786:Bone Substitutes / Q000737:chemistry / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D006801:Humans; D017655:Silicon Compounds / Q000737:chemistry / Q000494:pharmacology*; D013131:Spine / Q000166:cytology / Q000378:metabolism*
chemical_list: D018786:Bone Substitutes; D017655:Silicon Compounds; C032734:silicon nitride