الفهرس 
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Abstract
ABSTRACT
Patients with maxillofacial bone defects besides suffering physically, severely suffer psychologically. Bone grafts have been traditionally regarded as the gold standard for repairing these defects. However, with the increased complications caused by these grafts, the search for an alternative has become imperative. Consequently, bone tissue engineering (BTE) emerged as the long-aspired ultimate alternative. BTE enabled fabricating scaffolds with tailored properties. Recently, integrating one of the main pillars of Healthcare 4.0 i.e., bioprinting with BTE led to a paradigm shift in maxillofacial reconstruction, especially with the appearance of the patient-specific scaffolds. from this perspective, this thesis proposes designing and fabricating bone scaffolds that not only mimic the organic/inorganic composite structure of the bone but also mimic its 3D structure. The FDA-approved poly ε-caprolactone (PCL) polymer-based composites reinforced with different weight percentages (wt%) of the promising, green, yet affordable bioactive ceramic extracted from eggshell (ES) are prepared. Since all the commercially available bioprinters are not capable of handling such composites, building an ultra-affordable Heated Inductive-enabled Syringe Pump Extrusion (HISPE) multifunction open-source module is proposed in this thesis. The presented HISPE module enables converting any open-source fused deposition modeling (FDM) 3D printer into a bioprinter with extra advanced features such as 3D printing with materials that require melting in addition to regular bioprinters’ printing materials that do not require any heating. In the current study, the HISPE module was employed to print the proposed green PCL/ES scaffolds with a pore diameter of 350 µm without incorporating any toxic solvents. The effect of increasing the ES content from 0 wt% up to 30 wt% on the properties of the 3D printed scaffolds is explored through a series of mechanical, physicochemical, and in vitro water absorption and degradation testing. The experimental results showed that increasing the ES content up to 30 wt% improved the surface roughness and the compressive mechanical properties of the scaffolds. Moreover, the morphological characterizations proved that the produced scaffolds have an interconnected porous network without any clogs. from the in vitro testing, increasing the ES content has further improved the biodegradability and the water absorption of the scaffolds. Consequently, these scaffolds have a high potential for BTE especially for repairing maxillofacial bone defects. In practice, the scarcity of bioprinting centers worldwide hinders the spread of these patient-specific scaffolds and causes a huge load on the available centers. Moreover, the employment of these bioprinting centers in printing tissues and personalized (i.e., patient-specific) medicinal tables beside these BTE scaffolds plays a role in the escalation of this load. However, when these distributed centers are gathered and intelligently managed in the IoT (i.e., another pillar of Healthcare 4.0), the high demand for these time-critical scaffolds would be timely met and the pressure on the bioprinting centers would be eased. Therefore, this thesis presents, for the authors’ best knowledge for the first time in literature, two real-time green 3D bioprinting tasks’ (3DPTs) allocation and scheduling architectures tailored for the high load environments caused by the paucity of such bioprinting centers. The performance of the proposed architectures was investigated under extremely high-load environments. The experimental results proved the robustness and the scalability of the proposed architectures that surpasses their state-of-the-art counterparts. Besides respecting the real-time requirements of the 3DPTs, the proposed architectures improve the utilization of the 3DPs and guarantee an even workload distribution.