Doctoral Dissertations

Author

Qiang Fu

Abstract

"The main objectives of this dissertation were to explore the production of bioactive ceramic and glass scaffolds with oriented pore architectures by unidirectional freezing of suspensions, and to characterize the mechanical and biological performance of the scaffolds. Freezing of aqueous suspensions of hydroxyapatite (HA) or bioactive 13-93 glass particles resulted in the formation of scaffolds with a lamellar-type microstructure (pore width = 5-30 µm). The addition of polar organic solvents (such as 60 wt% dioxane) to the aqueous suspensions markedly changed the morphology and size of the oriented pores, giving scaffolds with a columnar-type microstructure and larger pre width (90-110 µm). The scaffolds showed a unique 'elastic-plastic' mechanical response in compression along the orientation direction, with large strain for failure (greater than 20%) and strain rate sensitivity. For a similar porosity, the bioactive glass scaffolds had a higher strength than the HA scaffolds, presumably because of better sintering characteristics. Columnar bioactive glass scaffolds (porosity = 55-60%) had a compressive strength of 25 ± 3 MPa. The columnar scaffolds with the larger pore width showed better ability than the lamellar scaffolds to support the proliferation and function of murine osteoblastic cells (MLO-A5 or MC3T3-E1). Subcutaneous implantation in the dorsum of rats showed abundant tissue ingrowth into the pores of the columnar scaffolds and integration of the scaffolds with surrounding tissue. The results indicate that bioactive 13-93 glass scaffolds with the columnar microstructure could be used for the repair of segmental defects in load-bearing bones"--Abstract, page v.

Advisor(s)

Rahaman, M. N., 1950-

Committee Member(s)

Brown, Roger F.
Bal, B. Sonny
Day, D. E.

Department(s)

Materials Science and Engineering

Degree Name

Ph. D. in Ceramic Engineering

Publisher

Missouri University of Science and Technology

Publication Date

Fall 2009

Journal article titles appearing in thesis/dissertation

  • Freeze casting of porous hydroxyapatite - I. Processing and microstructure
  • Freeze casting of porous hydroxyapatite scaffolds - II. Sintering, microstructure and mechanical behavior
  • Freeze-cast hydroxyapatite scaffolds for bone tissue engineering applications
  • Proliferation and function of MC3T3-E1 cells on freeze-cast hydroxyapatite scaffolds with oriented pore architectures
  • In vitro cell response to hydroxyapatite scaffolds with oriented pore architectures
  • Preparation and in vitro evaluation of bioactive glass (13-93) scaffolds with oriented microstructures for repair and regeneration of load-bearing bones
  • In vivo evaluation of 13-93 bioactive glass scaffolds with trabecular and oriented microstructures in a subcutaneous rat implantation model

Pagination

xxv, 294 pages

Note about bibliography

Includes bibliographical references.

Rights

© 2009 Qiang Fu, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Biomedical materials -- Testing
Glass in medicine
Hydroxyapatite
Tissue engineering

Thesis Number

T 9555

Print OCLC #

746026468

Electronic OCLC #

603721652

Share

 
COinS