MULTI-OBJECTIVE DESIGN AND CHARACTERIZATION OF ORTHOPAEDIC IMPLANTS AND META-BIOMATERIALS FABRICATED VIA ADDITIVE MANUFACTURING
Open Access
- Author:
- Tilton, Maryam
- Graduate Program:
- Mechanical Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- June 05, 2020
- Committee Members:
- Guhaprasanna Manogharan, Dissertation Advisor/Co-Advisor
Guhaprasanna Manogharan, Committee Chair/Co-Chair
Gregory Stephen Lewis, Committee Member
Reuben H Kraft, Committee Member
April D Armstrong, Outside Member
Michael W. Hast, Special Member
Daniel Connell Haworth, Program Head/Chair - Keywords:
- Additive manufacturing
Biomechanics
Mechanical behavior
Fracture fixation implants
Large bone defects
metamaterials - Abstract:
- Recent interests in development of multi-objective medical implants and biomaterials is largely due to the maturation of additive manufacturing (AM) which has enabled the realization of complex geometries at different length scales. Due to the digitally driven design and manufacturing advancements, a new generation of medical implants and meta-biomaterials have been emerging with a goal to address some of the critical clinical challenges, particularly in orthopaedics. For instance, limited design and manufacturing freedom of existing implants and biomaterials has led to increasing rates of implants failure and postoperative complications. Although there are growing efforts in this area, there is an important need to study and develop a comprehensive workflow for the design, AM and characterization of load-bearing orthopaedic implants at different length scales. This dissertation is focused on evaluating the biomechanical performance of the mathematically formulated metal AM implants and meta-biomaterials that exhibit enhanced mechanical properties when compared with the commercially available implants and biomaterials. Specifically, at the macroscale, the concept of patient-specific implants which are aimed to match the patient’s anatomy is investigated through numerical and experimental approaches in physiologically relevant conditions. Reconstruction of the Proximal humerus following complex fractures or tumor resection is employed as proof-of-concept in the macroscale studies. At the microscale, development and comprehensive evaluation of the structure-property relationships of AM meta-biomaterials are investigated. Outcomes of the study conducted at microscale indicate that the mechanical behavior and fracture mechanisms of the meta-biomaterials can be controlled based on both required topology and morphological properties. To the best of author’s knowledge, this is the first study that reports the transformation in the material responses, i.e. ductile to brittle behavior through microscale geometrical design.