Saudi Cultural Missions Theses & Dissertations
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Item Restricted Mechanical Properties of Custom-Made Post and Core Made of CAD/CAM Dental Ceramics(Queen Mary University of London, 2025) Almadi, Hussam; Karpukhina, Natalia; Cattell, Mike; Hill, Robert; Rashwan, MaherObjective: This study aimed to evaluate and compare the fracture resistance, failure modes, surface morphology, and crystallographic properties of three CAD/CAM fabricated post and core materials zirconia, resin nano ceramic, and experimental barium-based mica glass ceramic against a 3D-printed resin post and core used as a control. Materials and Methods: Sixty custom-designed post and core specimens (n = 15 per group) were fabricated and cemented into standardised resin tooth analogues. Four groups were tested: Group one - zirconia posts (CAD/CAM milled), Group two - resin nano ceramic posts (CAD/CAM milled), Group three - glass mica ceramic posts (CAD/CAM milled), and Group four - 3D-printed resin posts (control). All samples underwent static compressive loading until failure. Fracture resistance values were recorded and analysed using one-way ANOVA with post hoc Holm-Sidak comparisons (α = 0.05; power = 1.000). Failure modes were categorised under stereomicroscopy. Scanning electron microscopy (SEM) was performed to assess surface morphology and fracture patterns, and X-ray diffraction (XRD) was used to characterise the crystallographic structure of each material. Results: Zirconia exhibited the highest mean fracture resistance (1031.48 ± 150.40 N), but failed in a catastrophic, non-restorable manner. Resin nano ceramic (344.31 ± 71.21 N) and barium-based mica glass ceramic (377.29 ± 82.42 N) showed moderate strength and favourable, restorable failure modes, with SEM indicating energy dissipation through microcracking and crack deflection. The 3D-printed resin group showed the lowest fracture resistance (222.81 ± 10.87 N). SEM revealed distinct microstructural features for each material, while XRD confirmed the presence of densely packed polycrystalline zirconia and lamellar mica crystallites in the novel ceramic group. Conclusion: Material selection for post and core restorations should be based not only on fracture resistance but also on failure mode, microstructural behaviour, and retrievability. While zirconia offers superior strength, resin nano ceramic and the experimental mica-based ceramic demonstrate more favourable and restorable failure characteristics. Further research is recommended to investigate long-term fatigue resistance, modulus of elasticity via flexural testing, and performance in simulated clinical environments.10 0Item Restricted Tissue Engineering Strategies for Alveolar Bone Regeneration Using Silk-Based 3D-Printed Composite Scaffolds(Saudi Digital Library, 2025) Banjar, Ayman; Kaplan, DavidSuccessful regeneration of the alveolar ridge requires biomaterials that support both osteogenesis and vascularization. Combining biomaterials with 3D printing technology supports the fabrication of customized scaffolds with controlled architecture tailored to bone repair. This thesis explores two distinct tissue engineering strategies for bone regeneration using silk fibroin (SF)-based 3D printed scaffolds. The first approach involves SF-biphasic calcium phosphate (SF-BCP) scaffolds functionalized with bone morphogenetic protein-2 (BMP-2) and platelet-derived growth factor (PDGF), delivered using a heparinized hyaluronic acid-based hydrogel injected inside the scaffolds. The second strategy employed a cell co-culture-based regeneration approach using SF-bioactive glass (SF-BG) scaffolds designed to support the direct culture of human mesenchymal stem cells (hMSCs) with human umbilical vein endothelial cells (HUVECs) for vascularized bone tissue regeneration. The SF-BCP scaffolds were fabricated using an extrusionbased 3D printing method and characterized for their mechanical, structural, and rheological properties. Functionalization of the scaffolds with BMP-2 significantly enhanced early osteogenic differentiation, while PDGF had a limited effect. In parallel, SF-BG scaffolds were developed to support direct co-culture. The rheological and mechanical properties were suitable for the goals, but the printing process was sensitive to small changes in formulation and thus, less reliable. Coculture conditions were optimized on tissue culture polystyrene (TCPS) and then translated to the 3D printed scaffolds. The cells successfully adhered to the constructs, proliferated, and maintained increasing levels of metabolic activity over time. The scaffolds supported extracellular matrix deposition, with features varying depending on the ratios of hMSCs and HUVECs in the co-cultures. Altogether, this work demonstrates the potential of SF-based 3D printed scaffolds to support bone regeneration through bioengineering strategies tailored to enhance osteogenic outcomes. The findings of this work offer a foundation for the future design of silk-based scaffolds with potential applications in the regeneration of alveolar and craniofacial bone tissues.30 0Item Restricted DEVELOPMENT OF ADVANCED MULTI-NOZZLE MULTI-MATERIAL 3D PRINTING(Wayne State University, 2024) Alali, Mohammed; Almubarak, YaraExtrusion-based 3D printing methods, such as Direct Ink Writing, are extensively utilized across sectors like biomedical, energy, and electronics, employing a diverse range of materials. However, the lengthy printing times associated with single-nozzle systems limit their application in complex mass production and rapid prototyping. While multi-nozzle systems have attempted to address this issue, they often result in costly, and bulky setups with limited material options. This research introduces a novel multi-nozzle multi-material system that allows for simultaneous 3D printing using bent nozzles. The system is cost-effective, simple in design, and capable of printing a wide range of materials. Its universal design enables its integration with the commercially available printers and can reduce printing time by up to 90%. The capabilities of the multi-material setup are demonstrated through the 3D printing of soft, variable-stiffness elastomers for biomimetic robotic applications. Due to the rapid curing of elastomers in additive manufacturing, the change in mechanical properties of the 3D printed material were experimentally characterized. 3D printed ecoflex 00-10, Dragon skin 20, and a combination of both in layered format were evaluated. We then determined material parameters for incompressible hyperelastic strain energy function using the Mooney-Rivlin model (2nd, 3rd, and 5th order) and the Yeoh model (2nd and 3rd order). The Mooney-Rivlin model showed better alignment with experimental data, and these parameters were used to validate the results in ANSYS simulations. A fully 3D printed 100% elastomeric biomimetic octopus arm with gradient stiffness was successfully fabricated. A comparative study was conducted between the 100% elastomeric arm and an identical arm design integrated with metallic spring steel for controlled stiffness gradient. The elastomeric arm demonstrated controlled bending similar to the non-elastomeric version, validating the potential for 3D printing functionally gradient stiffness elastomers for robotic applications. Additionally, the developed model was used to predict the arm’s deformation through actuation via ANSYS simulation, which also aligned well with experimental results. Furthermore, this dissertation investigates the impact of printing parameters on oozing, a common problem affecting print quality in direct ink writing. The newly developed system, along with the parameter characterization, and oozing study, makes the multi-nozzle systems more affordable and capable of printing advanced material combinations with improved print quality. This breakthrough in additive manufacturing opens new avenues for fabricating entirely soft robotic structures with controlled variable stiffness configurations, offering better deformation control and improved functionality in high pressure environment, where the integration of rigid components presents significant challenges.6 0Item Restricted Dynamic Response of 3D-Printing Heterogeneous Beam(Cranfield University, 2023-08) Alhamdan, Naif; Khan, MuhammadHeterogeneous structures differ in composition, characteristics, and spatial distribution. These structures have non-uniform composition, features, or spatial distribution. High-temperature structural components and thermal barrier materials have been investigated for FGMs in aerospace engineering. Their design has also been utilised in high-speed aeronautical vehicles. This work predicts the dynamic response of inhomogeneous beams by studying structural factors' mechanical behaviour. Structures with inhomogeneity, such as fractures and segment locations, must behave reliably non many engineering applications. The study methodically examines how inhomogeneity, crack depth, and segment position affect fundamental frequency and resonance amplitude. The results indicate if that specific segment with lower infill density is far away from the beam's fixed end, the natural frequency results are higher. An empirical model with 0.96 R-square value was developed to estimate the fundamental frequency for the beam with local inhomogeneity and was validated.12 0Item Restricted Development of an in-vitro model for assessment of enamel demineralisation around orthodontic attachments for clear aligners treatment(University of Leeds, 2024-08) Almulhim, Almothana; Wood, David; Davies, Robert Philip Wynn; Altaie, AsmaaBackground: Improvements in dental materials and digital technology have produced removable, clear orthodontic appliances, consisting of consecutive semi-elastic polyurethane aligners able to force movement by placing composite resin attachments on the surface of the teeth. Orthodontic appliances have a history of causing enamel demineralisation because of the restoration used in treatment as an anchorage. Therefore, the study aims for the first time to develop an in-vitro model to measure the amount of enamel demineralisation around orthodontic composite attachments used in clear aligner treatment. Methods: Five premolar teeth obtained from the tissue bank received a baseline analysis of enamel density using Micro-CT and DIAGNOdent pen. Composite resin was placed, and a 3D-printed base model with an aligner was produced for the teeth to replicate clear aligner treatment. The samples were immersed in demineralistion and remineralisation solutions and mineral content reanalysed. Results: The study successfully produced a model that mimics a real human ridge with a gingival line and adjacent teeth. The chosen demineralisation solution was not able to produce a noticeable change in enamel mineralisation even with the gap found under the composite resin in Micro-CT; the DIAGNOdent pen proved an unreliable tool in this study. Conclusion: This study has laid the foundations for work on demineralisation associated with clear aligners, leaving future studies the ability to explore the gap that has been found and trying to further optimise demineralisation and remineralisation protocols, e.g. pH-cycling.18 0Item Restricted Building Value Layer by Layer: Costing Insights into 3D-printing Pharmaceuticals at the Point of Care.(King's College London, 2024-08) Alkhalaf, Lateen; Pacheco, Laurent; Alhanan, MohamedAim: This study aims to evaluate the economic profile of novel 3D-printed nadolol tablets using SSE 3DP technology and compares their costing to conventional compounding methods through various case scenarios involving different production volumes. Method: A comprehensive Total Cost of Ownership (TCO) model was implemented to assess direct and indirect costs associated with 3DP and conventional compounding methods. The study focused on two types of 3D printers, Felix V1.5 and DoserRx, to investigate their economic profiles and primary cost determinants in the production process costs of nadolol at 10 mg and 40 mg and to assess their cost efficiency compared to conventional compounding. Key cost factors were analysed, including raw materials, labour, energy consumption, maintenance, and amortisation of machines and equipment. Results: Amortisation of machines and equipment was identified as the primary cost determinant, comprising 58 % of the total production process costs. The study found that while At a low utilisation rate of 5% (one patient), the Felix V1.5 3D printer had an annual cost of nadolol 10 mg of £4,308. The DoserRx was higher at £16,780 compared to £1,596 for conventional compounding, representing a 90% increase in the total production cost. At full utilisation (100% or 24 patients), the gap in cost between DoserRx and conventional compounding narrowed to £41,086 while conventional is £3,830. DoserRx offered a more cost-efficient option for multiple production runs at a higher utilisation level. However, despite its high initial investment, the Felix V1.5 offered a comparable cost profile to DoserRx for multiple productions. DoserRx compounding remained competitive compared to other methods, saving up to 42% of the total cost. This highlights the importance of maximising machine utilisation to fabricate more pharmaceutical products to achieve economic viability. Conclusion: While 3D printing offers significant customisation benefits, its economic profile depends on the type of printer, the system used and achieving high utilisation of the 3DP machines to offset initial and operational costs. Although 3D-printed pharmaceuticals could be more cost-efficient for personalised medicines at the point of care, especially at higher utilisation rates of the machines and particularly for special populations of patients, conventional compounding remains a more economical option for small-volume production.23 0Item Restricted 3D-Printed Polycaprolactone Scaffolds for Temporomandibular Joint: Focus on Anatomical Precision(The University of Edinburgh, 2025) Alharbi, Saud; Paxton, JenniferBackground: Temporomandibular joint disorders (TMDs) significantly affect jaw function, leading to pain and compromised quality of life. Existing treatments, ranging from non-invasive therapies to surgical interventions, often fail to provide lasting solutions due to the complex anatomy and biomechanics of the TMJ. Aims: This study aims to develop anatomically precise 3D-printed polycaprolactone (PCL) scaffolds for TMJ tissue engineering, addressing current treatment limitations by providing a tailored approach that enhances the accuracy of fit and promotes tissue regeneration. Materials and Methods: The TMJ discs were prepared and scanned using structured-light 3D scanning technology to capture detailed anatomical features. PCL scaffolds were then fabricated using 3D printing techniques. Gross morphometrics measurements and statistical analyses were conducted to evaluate the accuracy and reproducibility of the printed scaffolds. Additionally, tissue culture experiments were performed to assess cell attachment and proliferation on the PCL scaffolds. Results: The structured-light 3D scanning provided high-resolution models of the TMJ discs, which were successfully used to produce precise PCL scaffolds. The morphometric analysis demonstrated that the scaffolds closely replicated the native disc's dimensions. Statistical analysis confirmed the reproducibility of the 3D printing process. Tissue culture experiments indicated zero cell attachment and growth on the PCL scaffolds, suggesting that significant modifications are needed to enhance their potential for supporting tissue regeneration. These findings highlight the necessity for further refinement in using 3D-printed scaffolds Conclusion: The study highlights the feasibility of using 3D-printed PCL scaffolds for TMJ tissue engineering. The anatomical precision achieved through structured-light 3D scanning and advanced printing techniques represents a significant advancement in developing personalized treatments for TMDs. Future research should focus on validating the clinical applicability of these scaffolds.12 0Item Restricted Evaluation of marginal and internal adaptation of fixed dental restorations on alveolar casts printed with different 3D printers.(Tufts University School of Dental Medicine Boston MA, 2024) Eidah, Rawan; Papaspyridakos, PanagiotisThis in-vitro study evaluates the marginal and internal adaptation of fixed dental restorations created using three different 3D printing technologies: Carbon Digital Light Synthesis™ (Carbon DLS™), Straumann P30, and Formlabs Form 3B+. A reference cast was prepared, digitized, and printed using the respective 3D printers. Measurements of adaptation were conducted utilizing a light microscope. The findings revealed significant differences in adaptation among the printers, particularly in the incisal buccal regions, with the Carbon DLS™ exhibiting superior performance, achieving the smallest mean marginal gap compared to the others. In contrast, non-significant differences were observed in the middle and cervical regions. The results underscore the importance of selecting suitable 3D printing technology to meet clinical requirements, suggesting that Carbon DLS™ is especially effective for complex dental restorations that require high precision. This study contributes valuable insights into the evolving field of digital dentistry, emphasizing the role of technology in enhancing patient outcomes in dental restorations. Keywords: Dental Restoration, 3D Printing, Marginal Adaptation, Internal Adaptation, Digital Dentistry, Prosthodontics47 0Item Restricted Reimaging the Nasrid Palace and Alhambra Vases in Emerging Islamic Studio Ceramics – A Multi-method Approach(Loughborough University, 2024-07-05) Basodan, Zelal Y.; Bernabei, Roberta; Harland, RobertThe core period of production of ‘Islamic Art’ occurred between the seventh and eighteenth centuries, before experiencing a significant decline particularly during the Western colonial periods. Nonetheless, Islamic art continued, and continues, to be produced. Ceramic art plays a key role in Islamic art and culture. Recently, in both the Middle East and in the West, there has been renewed interest in imitating the traditional Islamic patterns, especially geometric patterns. Since Heritage can be reactivated in the present, for the future, this makes it an imperative to revisit and revive (Harrison, 2010; Harvey, 2018). As such, there is a need to revisit the cultural heritage of Islamic Art and to recuperate it through the creative practices of contemporary artists in the present. After I investigated the practices of contemporary ceramics artists influenced by Islamic culture, I found relatively few of them, thus identifying an important lacuna. This highlighted an opportunity to make a significant new contribution. Therefore, this practice-based research explores the ceramic art of emerging Islamic studio ceramic by reviving cultural heritage artefacts. My research, by investigating the predominantly secular ceramics of Alhambra Palace and recuperating them in my own Islamic Studio Ceramics practice, aims to contribute towards a hybrid contemporary Islamic Studio Ceramics and to reinforce the notion that Islamic art can be created for secular purposes. Under the Nasrid dynasty (1237-1492), Islamic Spain produced artefacts that are examples of a lavish multi-cultural artistic style. With a contemporary lens this research explores the geometric ceramic tiles and Arabic poetry inscriptions – by Ibn Al-Jayyab and other poets – at Alhambra Palace, now situated within the UNESCO world heritage site of Alhambra, Generalife, and Albayaín in Granada, Spain. It also explores the concept and aesthetic of the superb Alhambra vases and the traditional reduction lustre technique used on these vases. These elements provide the theoretical and practical basis to stimulate a debate about the definition of Islamic art. This has been achieved through producing hybrid contemporary Islamic ceramic artefacts which utilise both traditional and new technological methods based on the Nasrid ceramics from Alhambra Palace in a cultural heritage. Alhambra vases were produced between the thirteenth and fifteenth centuries in Malaga under the Nasrid dynasty (1237-1492). These winged artefacts are believed to be the largest Islamic ceramic objects ever made, and the first artefacts to have such an intimate connection with the architecture. Due to the prestigious status of Alhambra vases, they were illustrated and replicated in the 19th century by European potters and designers. This demonstrates the cultural and artistic importance of these vases. Despite this, researchers in the Arab region have not studied Alhambra vases in much detail, and most studies about Islamic Granada have only focused on Alhambra Palace itself. Furthermore, in terms of practitioners in the Arab region, the current research has not hitherto identified any ceramic practices which reference Alhambra vases. Therefore, this research seeks to also examine Alhambra vases in the context of creative practice. This practice-based research thus uses a multi-method approach undertaken to allow for data collection from various sources, including field trips, a critical contextual review, reflection in action, and curatorial work. Accordingly, the creative practice of this research also takes ‘failures’ and serendipity, or so-called ‘happy accidents’, into consideration in informing these creative practices. This led to innovative findings about the use of lasers on fired ceramics, identifying a new method that can be applied by practitioners or designers and thus could influence the creative industry. Alhambra Palace, specifically, was chosen as the source of inspiration for this project due to the significance of its cultural heritage and its aesthetic excellence. Likewise, artistic ceramics have been chosen as the elected vehicle in adapting traditional concepts, patterns, and methods alongside new digital methods. This study also draws attention to a number of very significant cultural heritage artifacts that have hitherto been overlooked by researchers and practitioners from the Middle East. Consequently, this study will be of great value to practitioners, not only from the field of Islamic art, but also within the wider field of ceramics.41 0Item Restricted THE APPLICATIONS OF HAND-HELD THREE-DIMENSIONAL SCANNER AND THREE-DIMENSIONAL PRINTING IN BREAST ASSESSMENT(Saudi Digital Library, 2019-08-02) Alshehri, Sarah Abdulrahman F; Kalaskar, DeepakBackground: Despite the improvements in the diagnosis and treatment of breast disease, there remains a need to develop a tool capable of evaluating breast shape and volume objectively. With the advent of three-dimensional scanning and three-dimensional printing technologies, several attempts were made to explore their potential and applications in various disciplines of clinical practice. However, these efforts were not fully implied within the context of breast assessment and breast surgery. Purpose: The aim of this thesis was to investigate the applicability and accuracy of hand-held 3D surface scanners and 3D printers in the evaluation of breast shape and volume through the evaluation and comparison of various breast mannequins. Materials and Methods: To demonstrate the applicability of hand-held 3D surface scanning, the laser free surface-scanner Artec Eva device was investigated. The rationale of using this device was its feasibility, mobility and ability to provide high quality 3D scans in a short amount of time. Two scanning protocols were optimized and compared. Surface measurements were compared between the actual models and the 3D scanned images using one breast model, three different sized breast models and a defect created on a mannequin to mimic resected breast tissue. To assess the applicability of 3D printing within the context of breast assessment, the Flashforge Dreamer 3D printer was used. This printer utilizes Fused Filament Fabrication technology. Scan was processed and a 3D printed replica was produced. Comparisons were made between the original scan, the 3D printed replica and the actual model in terms of size and volume. Results and discussion: In terms of evaluating surface distances, the Artec Eva 3D scanner was able to assess the surface measurements of various breast models. With few statistically significant differences occurring between the actual models’ measurements and the measurements of the 3D scans. The first scanning protocol showed more accuracy. As the size of the breast model increased, accuracy improved. When 3D printed replicas were produced and compared to the dimensions and volumes of the actual models and the 3D scanned images, discrepancies were noted. The results were inconsistent and did not follow a certain pattern. Conclusion: This thesis investigated the applicability and accuracy of the hand-held 3D scanning device (Artec Eva 3D) and the Fused Filament Fabrication 3D printer (Flashforge Dreamer) within the context of objective breast shape and volume assessment. These technologies have the advantages of being feasible, fast and convenient. However, the increased costs, long processing time and the need for specific software training might limit its applications. Several limitations were identified which will need to be addressed in future work. Overall, this works shows an excellent opportunity for point of care of patients relative to the current methods used in breast assessment.20 0