Engineering Bioactive Polymers for the Next Generation of Bone RepairTable of Contents
List of Tables viii
List of Figures ix
Abstract xii
1. Introduction 1
2. Background 2
2.1. Human Bone 2
2.1.1. Structural and Material Properties of Bone 3
2.1.2. Mechanical Properties of Bone 4
2.1.3. Bone Cells 6
2.1.4. Bone Regeneration 7
2.2. Bone Replacements 8
2.2.1. Motivation 8
2.2.2. Requirements of Bone Replacement 9
2.3. Natural Bone Replacement 11
2.4. Synthetic Bone Replacement 14
2.4.1. Calcium Phosphate Materials and Bioactive Glasses 14
2.4.2. Biodegradable and Non-biodegradable Polymers 16
2.4.3. Ceramics / Polymer Composite 19
2.5. Tissue Engineered Scaffold 23
2.6. Injectable Materials 24
2.6.1. Polymeric Injectable Materials 24
2.6.2. Ceramic Injectable Materials 26
2.6.3. Injectable Composite Materials 27
3. Research Goals 33
4. An Solid Bioactive Polymeric Composites: HA/PMMA 35
4.1. Introduction 35
4.2. Materials and Methods 38
4.2.1. Material Processing 38
4.2.2. Bending Tests 39
4.2.3. Compression Test 39
4.2.4. Physicochemical Analysis 40
4.2.5. Nano-indentation 41
4.2.6. Data Analysis 43
4.3. Results 43
4.3.1. Global Bending Behavior 43
4.3.2. Local Mechanical Properties of HA 44
4.3.3. Local Interfacial Mechanical Properties 44
4.3.4. Surface Bioactivity 46
4.3.5. In vitro Global Elastic Mechanical Behavior 46
4.3.6. In vitro Interfacial Mechanical Properties 47
4.4. Discussion 48
4.5. Conclusion 55
5. An Alternative Approach to Bone Replacement 79
5.1. Introduction 79
5.2. Hydrogels 80
5.3. Poly(N-isopropylacryamide) 81
5.4. Preliminary Studies 83
5.4.1. PNIPAAm Co-polymer 83
5.4.2. Mechanical Properties of PNIPAAm-based Hydrogels 84
5.4.3. Bioactive Material Component 84
5.4.4. Phase Transformation 86
5.4.5. Rigid Polymer Supplement 87
5.4.6. Polymerization Kinetics 88
5.5. Summary 88
6. An injectable Bioactive Hydrogel Composite 97
6.1. Introduction 97
6.2. Materials and Methods 100
6.2.1. Synthesis PNIPAAm-MPS-PEGDM 100
6.2.2. Polymer Characterization 100
6.2.3. LCST Determination 101
6.2.4. Injectability and Viscosity Studies 101
6.2.5. Change in Volume Estimation 102
6.2.6. Bioactivity Characterization 102
6.2.7. In vitro Compressive Test 103
6.3. Results 104
6.3.1. Physical Properties 104
6.3.2. Bioactivity Kinetics 106
6.3.3. In vitro Mechanical Properties 108
6.4. Discussion 108
6.5. Conclusion 115
7. Future Work 131
8. Novel Contributions 133
List of References 135
Vita 152