Manipulation of Silicon Nitride Biomaterial Surfaces for Enhanced Osteoconductivity and Bacteriostasis

• 資料種別: 博士論文
• タイトル: Manipulation of Silicon Nitride Biomaterial Surfaces for Enhanced Osteoconductivity and Bacteriostasis
• 著者・編者: Ryan Matthew Bock
• 出版年月日等: 2017-03-24
• 出版年（W3CDTF）: 2017-03-24
• 並列タイトル等: 骨伝導性および静菌性を高めるための窒化ケイ素生体材料における表面処理
• 授与機関名: 京都工芸繊維大学
• 授与年月日: 2017-03-24
• 授与年月日（W3CDTF）: 2017-03-24
• 報告番号: 乙第206号
• 学位: 博士（工学）
• 博論授与番号: 乙第206号
• 本文の言語コード: eng
• 件名標目: Silicon nitride; SiYAlON; surface modification; surface chemistry; orthopaedic implants; biomaterial; bioceramic; surface charge; wetting; osteosarcoma; SaOS-2 cells; bacteria; bacteriostasis; hydroxyapatite formation
• 一般注記: Silicon nitride (Si3N4) has a distinctive combination of material properties desirable for orthopaedic implants, such as high strength and fracture toughness, phase stability, biocompatibility, hydrophilicity, radiotranslucency and resistance to biofilm formation. Its unique oxynitride surface, populated by native amino- and hydroxyl-terminated functional groups, lends itself to easy tuning via simple thermal, chemical, and mechanical treatments. In this thesis, Si3N4 surfaces subjected to various treatments, such as grinding and polishing, chemical etching, and annealing in nitrogen or air, were characterized using a variety of microscopic and spectroscopic techniques, streaming potential measurements, and static contact angle measurements. Significant differences in surface properties were observed with isoelectric points ranging from 2 to 5.6, and moderate to extremely hydrophilic water contact angles varying from ~65° to ~8°. With promising surface properties observed, in vitro tests using cells from the SaOS-2 line were employed for an assessment of the modified surfaces’ osteoconductive potential. While all Si3N4-derived surfaces were found to encourage osteoid production and mineralization, samples annealed in N2 exhibited by far the greatest volume of deposited hydroxyapatite. Further observation revealed that the cells preferentially clustered on islands of SiYAlON phase at the surface of these samples. Motivated by this result, a synthetic glaze designed to mimic the composition of the SiYAlON islands was applied to Si3N4 substrates and subjected to a similar battery of tests. As hypothesized, the glazed surfaces induced even more osteoid formation and mineralization than their N2-annealed precursors. In vitro testing was also employed to observe potential inhibition to biofilm formation by Staphylococcus epidermidis and Escherichia coli, both commonly responsible for post-surgical infection, due to changes in surface chemistry. It was found that treated surfaces retained all or most of as-fabricated Si3N4’s inherent resistance to biofilm formation. Further understanding was gleaned when Raman spectroscopy was employed to probe interactions between the samples and living cells, both SaOS-2 and the bacterium Porphyromonas gingivalis. Shifts in bands associated with metabolic indicators illuminated some of the mechanisms at play during these interactions. This work demonstrates that modification of Si3N4’s surface can enhance its native osteoconductivty without compromising its bacteriostatic character. Novel SiYAlON formulations show promise not just as a surface enhancement for silicon nitride, but also as a novel bioactive material that can be infused into or coated onto existing products to enable desirable biologic interactions.
• 国立国会図書館永続的識別子: info:ndljp/pid/11239207; https://dl.ndl.go.jp/pid/11239207
• コレクション（共通）: 障害者向け資料
• コレクション（障害者向け資料：レベル1）: テキストデータ
• コレクション（個別）: 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文; https://dl.ndl.go.jp/collections/A00014
• 収集根拠: 博士論文（自動収集）
• 受理日（W3CDTF）: 2019-02-03T04:35:56+09:00
• 記録形式（IMT）: application/pdf
• オンライン閲覧公開範囲: 国立国会図書館内限定公開
• デジタル化資料送信: 図書館・個人送信対象外
• 遠隔複写可否（NDL）: 可
• 掲載誌（URI）: http://hdl.handle.net/10212/2398
• 連携機関・データベース: 国立国会図書館 : 国立国会図書館デジタルコレクション; https://dl.ndl.go.jp