Doctoral Dissertations

Keywords and Phrases

Bioactive glass; Bone repair; Pore geometry; Porosity; Scaffolds; Selective laser sintering

Abstract

"Bone scaffold fabrication using powder-bed based additive manufacturing techniques, like the selective laser sintering (SLS) process, provides control over pore interconnectivity, pore geometry, and the overall shape of the scaffold, which aids in repairing different regions of the bone. The main objectives of this dissertation were to develop bioactive glass (BG) scaffolds using the SLS process and evaluate the scaffolds for their effectiveness in bone repair both in vitro and in vivo. 13-93 glass, a silicate based BG, and 13-93B3 glass, a borate based BG, are designed to accelerate the body's natural ability to heal itself and are used in this research. After the initial feasibility study, the material and process parameters were optimized to improve the compressive strength from ~20 MPa to ~41 MPa, for a 13-93 BG scaffold with a porosity of ~50%.

Pore geometry of the scaffold plays a crucial role as it not only affects the mechanical properties and subsequent degradation but also the bone cell proliferation. Scaffolds with a porosity of ~50% and five different pore geometries, namely, cubic, spherical, X, diamond, and gyroid, were fabricated and assessed in vitro for a possible preferential cell proliferation. The MTT labeling experiments indicated that the scaffolds with diamond and gyroid pore geometries have higher curvature-driven MLO-A5 cell proliferation. Finally, scaffolds with diamond and cubic pore geometries were evaluated in vivo using a rat calvarial defect model for 6 weeks. Though the results indicated no significant difference in the amount of new bone formation with respect to the defect region, the maturation of the fibrous tissue to bone appeared to be quicker in the scaffolds with diamond architecture"--Abstract, page iv.

Advisor(s)

Leu, M. C. (Ming-Chuan)
Hilmas, Greg

Committee Member(s)

Chandrashekhara, K.
Huang, Yue-Wern

Department(s)

Mechanical and Aerospace Engineering

Degree Name

Ph. D. in Mechanical Engineering

Sponsor(s)

National Science Foundation (U.S.)
United States. Office of Naval Research
University of Missouri Interdisciplinary Intercampus Research Program
Missouri University of Science and Technology. Intelligent Systems Center

Research Center/Lab(s)

Intelligent Systems Center

Publisher

Missouri University of Science and Technology

Publication Date

Fall 2015

Journal article titles appearing in thesis/dissertation

  • Effect of material, process parameters, and simulated body fluids on mechanical properties of 13-93 bioactive glass scaffolds by laser sintering
  • Effect of porosity and pore geometry of laser sintered bioactive glass scaffolds on mechanical properties
  • In vitro assessment of laser sintered bioactive glass scaffolds with different pore geometries

Pagination

xiii, 119 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2015 Krishna Chaitanya Reddy Kolan, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Subject Headings

Bone regenerationGlass in medicineBioactive compoundsTissue scaffoldsPorositySintering

Thesis Number

T 10828

Electronic OCLC #

936207733

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